Update potrace (1.13).

git-svn-id: svn://tug.org/texlive/trunk@39207 c570f23f-e606-0410-a88d-b1316a301751

61 files changed, 14039 insertions, 0 deletions

diff --git a/Build/source/libs/potrace/potrace-src/AUTHORS b/Build/source/libs/potrace/potrace-src/AUTHORS
new file mode 100644
index 00000000000..f6b22007218
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/AUTHORS
@@ -0,0 +1,11 @@
+Known contributors are listed here, in alphabetical order by their
+abbreviations (which are used in Changelog).
+
+Main author:
+
+ PS1 Peter Selinger <selinger at users.sourceforge.net>
+
+Contributors:
+
+ CH1 Christoph Hormann <chris_hormann at gmx.de> (GeoJSON backend)
+ TA1 Tor Andersson <tor at ghostscript.com> (PDF backend)
diff --git a/Build/source/libs/potrace/potrace-src/ChangeLog b/Build/source/libs/potrace/potrace-src/ChangeLog
new file mode 100644
index 00000000000..afee2358ed8
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/ChangeLog
@@ -0,0 +1,377 @@
+ChangeLog
+
+v1.13 2015/10/22
+	(2015/07/18) PS1 - fixed heap overflows, null pointer dereference
+	bugs and a memory leak. Reported by Agostino Sarubbo.
+	(2015/05/17) PS1 - man page: show which backends are dimension
+	based, and state more clearly that svg backend defaults to 72dpi.
+	(2015/04/11) PS1 - portability: ssize_t not supported on some
+	systems; use ptrdiff_t instead. Reported by Martin Gieseking.
+	(2015/03/28) PS1 - portability: added missing #includes for c99,
+	reported by Nelson Beebe.
+	(2015/03/27) PS1 - include config.h before other header files,
+	reported by Peter Breitenlohner.
+	(2015/03/26) PS1 - fixed division by zero bug triggered by bitmap
+	of dimension 1x0. Reported by Tomasz Buchert.
+
+v1.12 2015/03/24
+	(2015/03/20) PS1 - fixed memory overflow bug triggered by very
+	large bitmaps. Fixes RedHat bug #955808 reported by Vincent Danen
+	and Debian bug #778646 reported by Moritz Muehlenhoff.
+	(2014/09/06) PS1 - test suite: added binary-check, to check that
+	files are written in binary mode. Mostly relevant on Windows.
+	(2014/09/06) PS1 - portability: fixed potential binary file mode
+	bug on MinGW64.
+	(2014/03/30) PS1 - man pages: fixed leading blank page with
+	groff -man -Tps.
+	(2013/12/29) PS1 - portability: made regular expressions in test
+	suite POSIX compliant, reported by Ben Bullock.
+	(2013/05/14) PS1 - distribution: removed libtool from distribution.
+
+v1.11 2013/02/19
+	(2013/02/10) PS1 - bitops.c: added "cc" as a clobbered register.
+	(2012/09/13) PS1 - GeoJSON backend: -u option affects rounding,
+	not scaling.
+	(2012/09/12) CH1 - added GeoJSON backend.
+	(2012/03/04) PS1 - minor change in behavior of alphamax parameter:
+	make a corner if alpha >= alphamax (instead of >). This makes
+	little practical difference, except when alphamax = 0, in which
+	case we now get a polygon. Fixes bug #3495854, reported by
+	scribbleink.
+	(2012/02/24) PS1 - added support for BMP format with bitfields.
+
+v1.10 2011/08/19
+	(2011/08/07) PS1 - added --tight option
+	(2011/08/05) PS1 - backends: simplified dimension calculations
+	(2011/08/05) PS1 - eps backend: prevent integer overflow in
+	bounding box.
+	(2011/08/05) PS1 - disallow resolution of 0 dpi.
+	(2011/08/05) PS1 - man page: added BACKEND TYPES section
+	(2011/08/05) PS1 - fixed default scaling at 72dpi for
+	variable-sized backends
+	(2011/08/02) PS1 - new gimppath backend produces SVG output
+	suitable for current versions of Gimp.
+	(2011/08/02) PS1 - added a --flat option for the SVG backend.
+	(2011/07/31) PS1 - test suite: renamed *.out files to prevent make's
+	built-in implicit rules from accidentally overwriting them.
+	(2011/07/26) PS1 - added DXF backend. Thanks to Jonas Benedett
+	Dorr for testing.
+	(2011/07/26) PS1 - use high resolution bounding box in EPS, PDF,
+	and SVG backends
+	(2011/05/13) PS1 - autoconf: CADD can now be given at compile time
+
+v1.9 2010/12/21
+	(2010/12/20) PS1 - getopt.h: fixed compiler warnings
+	(2010/12/20) PS1 - added --tty option to specify progress bar
+	rendering at runtime.
+	(2010/12/20) PS1 - added simplified progress bar for Windows or
+	other dumb terminals. New --enable-dumb-tty configuration option.
+	(2010/12/16) PS1 - test suite: fixed bug where a failed test was
+	not reported in backend-check.sh
+	(2010/12/15) PS1 - test suite: support for $EXEEXT
+	(2010/12/15) PS1 - optimized penalty3 inner loop, 4.6% speedup.
+	(2010/12/15) PS1 - autoconf: new CADD variable to add to CFLAGS
+	(2010/12/15) PS1 - fixed some compiler warnings, added some error
+	handlers, and added some cosmetic top-level free's.
+	(2010/11/25) PS1 - added support for some BMP version 4 and 5
+	files, and for top-down BMP files. Suggested by Kanwar Sangwan.
+	(2010/11/13) PS1 - don't enter filter mode if -- is used
+	(2010/11/09) PS1 - greymap.h, bitmap.h: drop unneeded dependencies
+	(2010/09/07) PS1 - autoconf: fixed getopt_long test to allow
+	cross-compiling, bug #3061403, reported by Igor Filippov.
+	(2010/08/31) PS1 - test suite: added environment variables
+	CHECK_POTRACE and CHECK_MKBITMAP to allow binaries outside the
+	build tree to be tested
+	(2010/08/09) PS1 - autoconf: converted to libtool
+	(2010/08/05) PS1 - autoconf: renamed configure.in as configure.ac
+	(2010/08/05) PS1 - autoconf: added --with-libpotrace to optionally
+	install the Potrace library and header files.
+	(2009/08/03) PS1 - portability: c++ wrapper in potracelib.h,
+	suggested by Peter Jankuliak.
+	(2009/05/13) PS1 - added pdfpage backend for fixed pagesize PDF
+	output.
+	(2009/04/07) PS1 - decompose.c: minor optimization
+	(2008/10/08) PS1 - mkbitmap: speed increase by 8% to 26% by
+	eliminating unnecessary bounds checks and interpolation.
+	(2008/10/05) PS1 - trace.c: separate function for path reversal
+	(2008/10/03) PS1 - progress.h: do the right thing if progress ==
+	NULL
+	(2008/10/03) PS1 - moved detrand() to auxiliary.h
+	(2008/08/21) PS1 - mkbitmap: added --blur option.
+	(2008/08/12) PS1 - combined the old -V option with -v.
+	(2008/08/12) PS1 - test suite: adjusted tolerances to fix bug
+	#1745456
+	(2007/12/31) PS1 - include curve.h where path_t is used
+	(2007/12/28) PS1 - flush stderr when interleaved with stdout
+	(2007/12/28) PS1 - portability: don't hardcode size of short int
+	(2007/11/09) PS1 - eps backend: use save-restore to avoid
+	polluting caller's dictionary and for page independence.
+	(2007/05/22) PS1 - xfig backend: added depth to opaque components
+	to avoid them floating to the background. Suggested by Rafael
+	Laboissiere.
+
+v1.8 2007/04/09
+	(2007/04/08) PS1 - portability: use 'test' instead of '[' in shell
+	scripts.
+	(2007/04/08) PS1 - test suite: run PDF checks as a separate test.
+	(2007/04/06) PS1 - fixed logical expressions in flate.c
+	(2007/02/19) PS1 - portability: replacements for inline and M_PI
+	(2007/01/16) PS1 - test suite: added checks for rotation in
+	PostScript, PDF, and PGM backends
+	(2007/01/16) PS1 - pdf backend: added rotation
+	(2007/01/16) PS1 - pdf backend: renamed shipcom() function
+	(2007/01/14) PS1 - autoconf: check if getopt_long reorders its
+	arguments.
+	(2007/01/13) PS1 - made pseudo-random number generation
+	thread-safe and much faster.
+	(2006/12/20) PS1 - renamed some structures in lzw.c, main.h
+	(2006/12/20) PS1 - portability: fixed some compiler issues for
+	Amiga, reported by Andreas Kleinert.
+	(2006/12/20) PS1 - main.c: changed some return types to void.
+	(2006/08/14) PS1 - made curve.c:privcurve_free_members() static.
+	(2005/12/22) PS1 - renamed README.win as README-WIN
+	(2005/11/11) PS1 - portability: use binary file i/o in Cygwin.
+	Suggested by Henry He.
+	(2005/06/24) PS1 - potracelib: fixed allocation bug, reported by
+	Jung Shin.
+	(2005/06/23) PS1 - potracelib_demo.c: free resources properly.
+	(2005/06/23) PS1 - initialize unused private state to 0.
+	(2005/06/23) PS1 - decompose.c: improved memory allocation scheme.
+	(2005/05/06) PS1 - added "alphacurve" field to private curve
+	structure, so that backends that don't use the public interface
+	(such as the EPS backend) can be warned of non-conforming curves.
+
+v1.7 2005/03/06
+	(2005/03/05) PS1 - fixed progress bar subrange bug.
+
+v1.6 2005/02/27
+	(2005/02/22) PS1 - added "epsilon" feature to progress bar.
+	(2005/02/22) PS1 - documentation: changed potracelib documentation
+	to TeX format.
+	(2005/02/07) PS1 - tweaked progress bar
+	(2005/01/24) PS1 - added --progress option to potrace frontend.
+	(2005/01/24) PS1 - potracelib: added progress bar interface.
+	(2005/01/23) PS1 - fixed overflow bug in fast summing code.
+	(2005/01/23) PS1 - rewrote trace.c:bestpolygon(). This speeds up
+	potrace by 20% on typical data and up to 60% in some bad cases.
+	(2004/12/07) PS1 - documentation: added potracelib.txt
+	(2004/12/07) PS1 - renamed aux.h as auxiliary.h, since aux is an
+	invalid filename in Windows.
+	(2004/12/06) PS1 - API: added default parameters
+	(2004/12/06) PS1 - API: added potrace_state_t
+	(2004/12/06) PS1 - API: added "const" qualifiers
+	(2004/12/06) PS1 - removed conv and areac fields from privpath_t.
+	(2004/12/06) PS1 - changed bounding box handling in decompose.c
+	(2004/12/06) PS1 - split curve_t into public and private parts.
+	(2004/12/06) PS1 - moved curve/path allocation to curve.c.
+	(2004/12/06) PS1 - renamed a type in lzw.h.
+	(2004/12/06) PS1 - renamed source files.
+	(2004/12/04) PS1 - split path_t into public and private parts.
+	(2004/12/03) PS1 - split core functionality from user interface.
+	(2004/12/03) PS1 - moved parts of bitmap.h to potracelib.h. Split
+	bitmap.c into bitmap.c and bitmap_io.c. Moved path decomposition
+	auxiliary functions from bitmap.c to path.c.
+	(2004/12/03) PS1 - converted some stray local functions to static
+	(2004/12/01) PS1 - moved basic curve data type definitions to
+	potracelib.h
+	(2004/12/01) PS1 - collected some repeatedly used macros in aux.h
+	(2004/12/01) PS1 - started to create API to potrace core
+	functionality in potracelib.c and potracelib.h. Also added new
+	libpotrace.a target.
+	(2004/12/01) PS1 - made curve.c and path.c reentrant by removing
+	global variable "info".
+	(2004/11/28) PS1 - made a85* auxiliary functions static in
+	flate.c.
+	(2004/11/28) PS1 - pdf backend: removed arbitrary page limit.
+	(2004/11/24) PS1 - pdf backend: replaced ftell() by explicit byte
+	count to work correctly with stdout.
+	(2004/11/24) PS1 - portability: use binary file i/o in MinGW.
+	(2004/10/08) PS1 - minor cleanup in backend_pdf.c.
+	(2004/09/21) PS1 - replace -O3 compilation default by -O2; inlined
+	critical functions manually instead.
+	(2004/09/18) PS1 - slightly optimized multiplications in
+	curve.c:bezier(). Thanks to Thomas M.Ott for suggesting it.
+	(2004/09/16) PS1 - list of backends in help message is now
+	generated.
+	(2004/09/16) PS1 - test suite: added test for pdf backend.
+	(2004/09/14) PS1 - removed bits.c, renamed bits.h to bitops.h, and
+	use static inline functions instead of macros.
+	(2004/09/14) PS1 - test suite: adjusted tolerances.
+	(2004/09/12) PS1 - mkbitmap: when reading plain pbm files, use
+	colors 0 and 255, not 0 and 1.
+	(2004/09/12) PS1 - potrace and mkbitmap: don't complain about
+	"junk at the end of file" if the junk is whitespace and
+	comments. Treat files which contain only whitespace and comments
+	as empty.
+	(2004/08/05) TA1 - added pdf backend.
+
+v1.5 2004/07/08
+	(2004/07/08) PS1 - removed dependency on external "compress"
+	program. Removed ztops.c, added lzw.c, bits.c.
+	(2004/03/17) PS1 - don't leave temporary file /tmp/have_compress.*
+	lying around.
+	(2004/03/06) PS1 - fixed a type error in have_compress.c:28.
+
+v1.4 2004/03/06
+	(2004/03/05) PS1 - removed the compile-time check for the
+	"compress" program and replaced it by a run-time check.
+	(2004/03/03) PS1 - ztops.c: fixed compression bug where garbage
+	was added after the end of stream.
+	(2004/02/09) PS1 - further optimized the speed of the function
+	path.c:pathlist_to_tree, which now takes less than 0.1% of total
+	running time.
+	(2004/02/09) PS1 - distribution: removed potrace.{ps,pdf} from
+	distribution, changed textfiles to DOS mode in Cygwin distribution
+	(2004/01/19) PS1 - corrected a bug in 1.2 which caused an enormous
+	slowdown in the function path.c:pathlist_to_tree.
+	(2004/01/17) PS1 - test suite: better quoting in shell scripts to
+	be more robust against spaces in filenames etc.
+	(2004/01/17) PS1 - test suite and ztops.c: respect TEMPDIR
+	environment variable, if set.
+
+v1.3 2004/01/15
+	(2004/01/14) PS1 - test suite: adjusted tolerances.
+	(2004/01/13) PS1 - when reading a bitmap of width or height 0,
+	pretend the offending dimension is 1. This is not 100% logical
+	in all cases, but better than producing garbage.
+	(2004/01/13) PS1 - fixed bounding box in xfig backend.
+	(2004/01/13) PS1 - added missing gsave/grestore to ps backend.
+	(2004/01/07) PS1 - autoconf: search for zlib.h in
+	${prefix}/include and for libz.so in ${prefix}/lib, in case they
+	are not found elsewhere.
+	(2004/01/07) PS1 - eliminated some unused variables.
+        (2004/01/07) PS1 - portability: eliminated typeof() from
+	mkbitmap.c
+	(2004/01/07) PS1 - test suite: added a test for empty bitmaps.
+	(2003/12/25) PS1 - fixed bug #866223: potrace crashes when applied
+	to an empty bitmap.
+	(2003/12/25) PS1 - when options -2 or -3 are unsupported, ignore
+	them rather than failing, for improved compatibility.
+	(2003/12/25) PS1 - autoconf: added --disable-zlib configuration
+	option and improved error messages for missing zlib.h or libz.so
+	(2003/12/25) PS1 - portability: eliminated dynamic arrays in
+	mkbitmap.c
+	(2003/12/25) PS1 - test suite: added a check for mkbitmap.
+	(2003/12/25) PS1 - test suite: more portable filesize checking in
+	backend-check.sh
+
+v1.2 2003/12/23
+	(2003/12/23) PS1 - added an xfig backend.
+	(2003/12/23) PS1 - added --group option to group related shapes
+	together in SVG backend.
+	(2003/12/23) PS1 - added --opaque option to paint white shapes
+	opaquely, instead of leaving them transparent, in PS/EPS and SVG
+	backends.
+	(2003/12/23) PS1 - rewrote path decomposition algorithm to
+	calculate path containment tree, to be used for grouping.
+	(2003/12/23) PS1 - test suite: added a check of postscript output
+	using ghostscript.
+	(2003/09/18) PS1 - autoconf: added tests for -lm and -lz
+	libraries, and for zlib.h header file.
+	(2003/09/18) PS1 - portability: cleaned up code so that it can be
+	compiled with a C++ compiler.
+	(2003/09/17) PS1 - code cleanup in main.c:main().
+	(2003/09/17) PS1 - added mkbitmap program.
+	(2003/09/17) PS1 - added -ffloat-store compiler flag for improved
+	floating point predictability.
+	(2003/09/12) PS1 - test suite: added test for BMP runlength
+	encoding.
+	(2003/09/12) PS1 - fixed frontend for BMP runlength encoding.
+	(2003/09/11) PS1 - autoconf: added test to work around gcc
+	compiler bug 12243, which affected curve.c:adjust_vertices().
+	(2003/09/11) PS1 - renamed pbm.c as bitmap.c, pgm.c as greymap.c
+	(2003/09/11) PS1 - moved some bitmap details from path.c to pbm.c
+	(2003/09/10) PS1 - renamed pbm.h macros to start with BM_
+	(2003/09/02) PS1 - portability: added missing fallback value for
+	M_PI to backend_pgm.c.
+	(2003/08/28) PS1 - specialized matrix solving code for n=2.
+	(2003/08/28) PS1 - portability (and scalability): eliminated
+	dynamic arrays.
+	(2003/08/28) PS1 - portability: replaced vsnprintf by vsprintf.
+	(2003/08/28) PS1 - portability: provided fallback value for M_PI
+	(2003/08/27) PS1 - autoconf: now checks whether the compress
+	program works, not just whether it exists.
+	(2003/08/27) PS1 - test suite: wrote three tests for "make check"
+	(2003/08/27) PS1 - portability: fixed some floating point errors
+	on DEC Alpha: division by zero and log of zero.
+	(2003/08/27) PS1 - changed bitmap representation to take advantage
+	of 64-bit architectures.
+	(2003/08/27) PS1 - changed default scaling in ps and eps modes for
+	small page sizes.
+	(2003/08/26) PS1 - allow arguments of command line options -b, -z,
+	-P to be abbreviated by "unambiguous prefix".
+	(2003/08/26) PS1 - added rotation to gimppath backend.
+	(2003/08/24) PS1 - portability: removed GNU extensions from printf
+	format strings in backend_eps.
+	(2003/08/22) PS1 - converted --unit to double value.
+	(2003/08/22) PS1 - added experimental gimppath backend.
+	(2003/08/20) PS1 - close paths in postscript/eps backend.
+	(2003/08/20) PS1 - fixed bug in parsing command line options: long
+	options --cleartext, --level2, --level3 did not work properly.
+	Thanks to George Williams for reporting this bug.
+
+v1.1 2003/08/18
+	(2003/08/17) PS1 - replaced calc_lon algorithm by a faster
+	implementation. This results in speedups of up to factor 3.3 for
+	certain large input files.
+	(2003/08/17) PS1 - added --invert option.
+	(2003/08/17) PS1 - improved error messages on wrong file format.
+	(2003/08/17) PS1 - code cleanup to build under fussier compilers.
+	Thanks to Nelson Beebe for submitting compiler logs for a large
+	number of setups.
+	(2003/08/17) PS1 - renamed curve.c:quad as quadform to avoid name
+	clash on IBM AIX, Compaq/DEC ODF/1.
+	(2003/08/17) PS1 - autoconf: let user override CFLAGS at configure
+	time, and use -Wall and -O3 only for gcc compiler
+	(2003/08/16) PS1 - added --blacklevel option to control
+	image-to-bitmap conversion
+	(2003/08/16) PS1 - added ability to read BMP files. Changed error
+	reporting in case of empty files, or if there is junk at the end
+	of a file in multipage mode.
+	(2003/08/14) PS1 - as a convenience, now also read files in PGM
+	and PPM format and convert to bitmap by simple threshold method.
+	This is because many programs, including the Gimp and the *topnm
+	tools, produce PNM output which must be further converted to PBM.
+	(2003/08/14) PS1 - rearranged order of options in usage message.
+	(2003/08/14) PS1 - implemented -d1 option for SVG backend. This
+	outputs a jaggy bitmap with no smoothing.
+	(2003/08/14) PS1 - autoconf: improved handling of
+	--enable-compress
+	(2003/08/14) PS1 - added SVG backend.
+	(2003/08/14) PS1 - renamed old -s option as -S
+	(2003/08/12) PS1 - added README.win
+	(2003/08/12) PS1 - autoconf: fixed bug #787182: added non-standard
+	compile time options to help message for ./configure script
+
+v1.0 2003/08/10
+	(2003/08/10) PS1 - added file i/o code
+	(2003/08/08) PS1 - optimized number of times the penalty3 function
+	is called. Speedups of factor 2.7 were observed on large files.
+	(2003/08/08) PS1 - added --opttolerance and --alphamax options.
+	(2003/08/07) PS1 - autoconf: changed configure.in so that test for
+	compress is omitted when the user overrides it - this prevents a
+	wrong cached value to be read.
+	(2003/08/07) PS1 - keep output flushed in postscript mode
+	(2003/08/07) PS1 - fixed memory leak in multiple page mode
+	(2003/08/06) PS1 - replaced --opticurve by --longcurve option;
+	opticurve is now the default
+	(2003/08/06) PS1 - added opticurve sensitivity to pgm backend
+	(2003/08/06) PS1 - restricted opticurves to be bounded away from
+	180 degrees
+	(2003/08/06) PS1 - allow margins and papersize to determine width
+	if it is not defined by other means in postscript mode
+	(2003/08/06) PS1 - added ability to read multiple bitmaps in
+	postscript mode
+	(2003/08/05) PS1 - new --longcoding option
+	(2003/08/05) PS1 - new optimized eps backend which works with
+	opticurve.
+	(2003/07/31) PS1 - replaced O(n^3) calc_lon algorithm by a new
+	O(n^2) algorithm. Observed speedups of factor 80.
+	(2003/07/27) PS1 - added --opticurve option and integrated
+	opticurve code in curve.c
+	(2003/06/04) PS1 - made bm_to_pathlist a lot more efficient by
+	scanning and clearing only bounding box of mask in inner scan.
+	(2002/11/17) PS1 - changed bm_to_pathlist prototype to use
+	explicit return value.
+	(2002/10/09) PS1 - autoconf: added automake/autoconf scripts in
+	preparation for public distribution.
diff --git a/Build/source/libs/potrace/potrace-src/Makefile.am b/Build/source/libs/potrace/potrace-src/Makefile.am
new file mode 100644
index 00000000000..f6a17faf852
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/Makefile.am
@@ -0,0 +1,11 @@
+## Copyright (C) 2001-2015 Peter Selinger.
+## This file is part of Potrace. It is free software and it is covered
+## by the GNU General Public License. See the file COPYING for details.
+
+## Process this file with automake to produce Makefile.in
+
+EXTRA_DIST = README-WIN
+
+ACLOCAL_AMFLAGS = -I m4
+
+SUBDIRS = src doc check
diff --git a/Build/source/libs/potrace/potrace-src/NEWS b/Build/source/libs/potrace/potrace-src/NEWS
new file mode 100644
index 00000000000..6571a44ece2
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/NEWS
@@ -0,0 +1,127 @@
+October 22, 2015: Release 1.13
+
+ Some critical bugs in the processing of BMP files were fixed. These
+ bugs allowed the program to be crashed, or potentially to be abused
+ in other ways, by feeding it specially crafted BMP files. Thanks to
+ Tomasz Buchert and Agostino Sarubbo for reporting these bugs.
+ Portability was improved for C99 and for MSVC++. Thanks to Peter
+ Breitenlohner, Nelson Beebe, and Martin Gieseking for reporting
+ portability issues.
+
+March 24, 2015: Release 1.12
+
+ Fixed memory overflow bug triggered by very large bitmaps. Fixed
+ binary file mode on 64-bit Windows. Portability improvements.
+
+February 19, 2013: Release 1.11
+
+ A GeoJSON backend was added; thanks to Christoph Hormann for
+ contributing this. Support for bitfields in the BMP format was
+ added. A minor change was made to the behavior of the alphamax
+ parameter; a value of 0 now gives a true polygon.
+
+August 19, 2011: Release 1.10
+
+ A DXF backend was added. The output is in the drawing interchange
+ format used by computer aided design software. Thanks to Jonas
+ Benedett Dorr for testing. The Gimppath backend was changed to be
+ compatible with current versions of Gimp. The EPS, PDF, and SVG
+ backends now use high-resolution bounding boxes. The default scaling
+ of the EPS, PDF, and SVG backends is now fixed at 72dpi. A new option
+ --flat was added to the SVG backend. A new option --tight was added
+ to remove whitespace around the input image before calculating its
+ scaling and placement.
+
+December 21, 2010: Release 1.9
+
+ The xfig and eps backends were improved, and a fixed pagesize PDF
+ backend was added. Support for BMP version 4 and version 5 files, as
+ well as top-down BMP files, was added. Minor speed improvements to
+ Potrace and major speed improvements to mkbitmap. A Gaussian blur
+ option was added to mkbitmap. Libtool is now used to build and
+ optionally install the Potrace library. An optional simplified
+ progress bar was added for dumb terminals. This release also contains
+ some portability improvements, cross-compilation improvements, and
+ minor bug fixes.
+
+April 9, 2007: Release 1.8
+
+ This release contains minor bugfixes and portability improvements.
+ Rotation is now implemented in the PDF backend.
+
+March 6, 2005: Release 1.7
+ 
+ This is a bugfix release. A bug in the progress bar code, which
+ caused arithmetic exceptions on some 64-bit architectures, has been
+ fixed.
+
+February 27, 2005: Release 1.6
+
+ This release contains an algorithm improvement that leads to a
+ speedup of 20-60% over previous versions of Potrace. A new PDF
+ backend was added, courtesy of Tor Andersson. An option --progress
+ was added for displaying a progress bar. The Windows version of
+ Potrace now uses MinGW instead of Cygwin, eliminating the need to
+ install a special DLL alongside the executable programs, and solving
+ some problems with wildcards and executable PostScript files. Some
+ spurious "premature end of file" messages were eliminated. The
+ core functionality of Potrace was separated into a library with a
+ documented API, making it easier for developers to incorporate
+ Potrace into other GPL-licensed software.
+
+July 8, 2004: Release 1.5
+
+ The LZW patent has finally expired in Canada. Therefore, postscript
+ level 2 compression can now be implemented directly within Potrace,
+ without having to rely on the external "compress" program. This
+ release makes the necessary corrections.
+
+March 6, 2004: Release 1.4
+
+ This is a bugfix release. Fixed the bug which sometimes caused
+ Potrace to "hang" on large input files. Also fixed some bugs in the
+ compression code. The presence of the "compress" program is now
+ determined at run-time, rather than compile-time. No new features or
+ command line options were added.
+
+January 15, 2004: Release 1.3
+
+ This is primarily a bugfix release. Version 1.2 fatally crashed when
+ applied to an empty (all white) bitmap. The options -2 and -3 are now
+ ignored when unsupported, rather than causing an error.  There were
+ some improvements to the test suite, autoconfiguration, and
+ portability. The bounding box in the xfig backend was fixed, and the
+ postscript output now has better page encapsulation. Bitmaps of
+ dimension 0 are now tolerated better.
+
+December 23, 2003: Release 1.2
+
+ New experimental Gimppath and XFig backends were added.  A separate
+ program mkbitmap was added, which can be used as a preprocessor to
+ Potrace. It turns greyscale or color images into high-quality
+ bitmaps with optional scaling and filtering. New options --opaque,
+ --group, and --fillcolor were added for greater flexibility in
+ generating editable PostScript and SVG output. The bitmap
+ decomposition algorithm was improved and can now take advantage of
+ 64-bit platforms.  Portability and autoconfiguration were vastly
+ improved, and a test suite was added. Runlength encoded BMP files can
+ now be read. Some bugs in command line options were fixed.
+
+August 18, 2003: Release 1.1
+
+ The most important new feature of this release is an SVG (scalable
+ vector graphics) backend. This file format can be read by vector
+ graphics manipulation programs such as sodipodi, as well as web
+ browsers with an SVG plugin. I also added PGM, PPM, and BMP as
+ additional input file formats. The new --blacklevel and --invert
+ options control how non-black-and-white images are converted to
+ bitmaps before being processed by Potrace. The implementation of a
+ critical function has been improved to make Potrace even faster on
+ large input files; this results in speedups of up to factor 3.3
+ relative to Potrace 1.0. Autoconfiguration was improved, and the code
+ was polished to compile on more different architectures. The error
+ messages for wrong file formats were also improved.
+
+August 10, 2003: Release 1.0
+
+ First public release.
diff --git a/Build/source/libs/potrace/potrace-src/README b/Build/source/libs/potrace/potrace-src/README
new file mode 100644
index 00000000000..b29197ea0e1
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/README
@@ -0,0 +1,183 @@
+
+	   POTRACE - transform bitmaps into vector graphics
+			
+				* * *
+	   
+DESCRIPTION
+
+ Potrace is a tool for tracing a bitmap, which means, transforming a
+ bitmap into a smooth, scalable image.  The input is a bitmap (PBM,
+ PGM, PPM, or BMP), and the default output is one of several vector
+ file formats.  A typical use is to create EPS files from scanned
+ data, such as company or university logos, handwritten notes, etc.
+ The resulting image is not "jaggy" like a bitmap, but smooth. It can
+ then be rendered at any resolution.
+
+ Potrace can currently produce the following output formats: EPS,
+ PostScript, PDF, SVG (scalable vector graphics), DXF, GeoJSON, PGM
+ (for easy antialiasing of pixel-based images), Gimppath, and
+ XFig. Additional backends might be added in the future.
+
+ A separate program, mkbitmap, is also provided. This program can act
+ as a pre-processor for Potrace, applying scaling and various filters
+ to an image before converting it to a bitmap. This is useful for
+ potracing greyscale and color images.
+
+DEPENDENCIES
+
+ Potrace relies on the zlib library for PostScript level 3
+ compression. This library is pre-installed on most modern systems. 
+ If not present, it can be obtained from http://www.gzip.org/zlib/.
+
+COMPILATION
+
+ For generic compilation instructions, see the file INSTALL.  In
+ addition, the following compile time options (options to ./configure)
+ are supported. 
+
+  --with-libpotrace       install Potrace library and headers (default: no)
+  --disable-zlib          disable PostScript level 3 compression
+  --enable-metric         use metric units (centimeters) as default
+  --enable-a4             use a4 as the default papersize
+  --enable-dumb-tty       use simplified ASCII-only progress bar
+
+ See also ./configure --help.
+
+INSTALLING
+
+ If you are installing from sources, just do "make install" as root.
+ If you are installing from a binary distribution, just copy the
+ "potrace" and "mkbitmap" binaries to a place where the operating
+ system expects them, such as /usr/local/bin. Also copy the files
+ "potrace.1" and "mkbitmap.1" to a directory where the operating
+ system looks for man pages, such as /usr/local/man/man1. For
+ instructions on installing Potrace under Windows, see the file
+ README-WIN
+
+USAGE
+
+ For more detailed usage information, see the man page.
+
+ Usage: potrace [options] [filename...]
+ General options:
+  -h, --help                 - print this help message and exit
+  -v, --version              - print version info and exit
+  -l, --license              - print license info and exit
+ File selection:
+  <filename>                 - an input file
+  -o, --output <filename>    - write all output to this file
+  --                         - end of options; 0 or more input filenames follow
+ Backend selection:
+  -b, --backend <name>       - select backend by name
+  -e, --eps                  - EPS backend (encapsulated PostScript) (default)
+  -p, --postscript           - PostScript backend
+  -s, --svg                  - SVG backend (scalable vector graphics)
+  -g, --pgm                  - PGM backend (portable greymap)
+  -b pdf                     - PDF backend (portable document format)
+  -b pdfpage                 - fixed page-size PDF backend
+  -b dxf                     - DXF backend (drawing interchange format)
+  -b geojson                 - GeoJSON backend
+  -b gimppath                - Gimppath backend (GNU Gimp)
+  -b xfig                    - XFig backend
+ Algorithm options:
+  -z, --turnpolicy <policy>  - how to resolve ambiguities in path decomposition
+  -t, --turdsize <n>         - suppress speckles of up to this size (default 2)
+  -a, --alphamax <n>         - corner threshold parameter (default 1)
+  -n, --longcurve            - turn off curve optimization
+  -O, --opttolerance <n>     - curve optimization tolerance (default 0.2)
+  -u, --unit <n>             - quantize output to 1/unit pixels (default 10)
+  -d, --debug <n>            - produce debugging output of type n (n=1,2,3)
+ Scaling and placement options:
+  -P, --pagesize <format>    - page size (default is letter)
+  -W, --width <dim>          - width of output image
+  -H, --height <dim>         - height of output image
+  -r, --resolution <n>[x<n>] - resolution (in dpi) (dimension-based backends)
+  -x, --scale <n>[x<n>]      - scaling factor (pixel-based backends)
+  -S, --stretch <n>          - yresolution/xresolution
+  -A, --rotate <angle>       - rotate counterclockwise by angle
+  -M, --margin <dim>         - margin
+  -L, --leftmargin <dim>     - left margin
+  -R, --rightmargin <dim>    - right margin
+  -T, --topmargin <dim>      - top margin
+  -B, --bottommargin <dim>   - bottom margin
+  --tight                    - remove whitespace around the input image
+ Color options, supported by some backends:
+  -C, --color #rrggbb        - set foreground color (default black)
+  --fillcolor #rrggbb        - set fill color (default transparent)
+  --opaque                   - make white shapes opaque
+ SVG options:
+  --group                    - group related paths together
+  --flat                     - whole image as a single path
+ Postscript/EPS/PDF options:
+  -c, --cleartext            - do not compress the output
+  -2, --level2               - use postscript level 2 compression (default)
+  -3, --level3               - use postscript level 3 compression
+  -q, --longcoding           - do not optimize for file size
+ PGM options:
+  -G, --gamma <n>            - gamma value for anti-aliasing (default 2.2)
+ Frontend options:
+  -k, --blacklevel <n>       - black/white cutoff in input file (default 0.5)
+  -i, --invert               - invert bitmap
+ Progress bar options:
+  --progress                 - show progress bar
+  --tty <mode>               - progress bar rendering: vt100 or dumb
+ 
+ Dimensions can have optional units, e.g. 6.5in, 15cm, 100pt.
+ Default is inches (or pixels for pgm, dxf, and gimppath backends).
+ Possible input file formats are: pnm (pbm, pgm, ppm), bmp.
+ Backends are: eps, postscript, ps, pdf, pdfpage, svg, dxf, geojson, pgm, 
+ gimppath, xfig.
+
+POTRACE LIBRARY (FOR DEVELOPERS)
+
+ As of Potrace release 1.6, the Potrace core functionality has been
+ separated into a library libpotrace.a. This makes it easy to integrate
+ tracing functionality into other GPL programs. The API of the library
+ is defined in the header file potracelib.h, and is documented in
+ doc/potracelib.pdf. It is not by default installed, but can be
+ installed with the --with-libpotrace configuration option.
+
+DOCUMENTATION
+
+ Usage information is contained in the man page:
+ http://potrace.sourceforge.net/potrace.html
+
+ Many common questions are answered in the FAQ:
+ http://potrace.sourceforge.net/faq.html
+
+ Some examples are given on the following web pages:
+ http://potrace.sourceforge.net/samples.html
+ http://potrace.sourceforge.net/mkbitmap.html
+
+ The inner workings of the potrace algorithm are explained here:
+ http://potrace.sourceforge.net/potrace.pdf
+
+ The potrace library is documented here:
+ http://potrace.sourceforge.net/potracelib.pdf
+
+COPYRIGHT
+
+ Copyright (C) 2001-2015 Peter Selinger
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or (at
+ your option) any later version.
+
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation, 
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 
+ See also http://www.gnu.org/.
+
+ See the file COPYING for details.
+
+GPG KEY
+
+ The key fingerprint of Peter Selinger's GPG key is:
+ 12A2 4B3C 3790 B688 E484  7A98 A68B CC37 CA31 696A
+ This may be useful for authenticating future versions of Potrace.
diff --git a/Build/source/libs/potrace/potrace-src/README-WIN b/Build/source/libs/potrace/potrace-src/README-WIN
new file mode 100644
index 00000000000..ff16913c8ee
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/README-WIN
@@ -0,0 +1,65 @@
+
+	   POTRACE - transform bitmaps into vector graphics
+
+			  README for Windows
+  _________________________________________________________________
+
+This file contains instructions specific to the pre-compiled Windows
+distribution of Potrace. Please see the general README file and the
+man page for general information on usage, how to compile Potrace,
+etc.
+
+
+INSTALLATION for Windows 95/98/2000/NT/XP/Vista/7/whatever:
+===========================================================
+
+Download the file potrace-XXX.win32.zip (or potrace-XXX.win64.zip if
+you want the 64-bit version).  Unpack it with your favorite unzipping
+tool, such as unzip, 7-Zip, WinZip, or just right-clicking on the
+file.
+
+If you have "tar" and "gunzip" installed, you may also get the tar.gz
+file instead of the zip file.
+
+The distribution includes the executable programs potrace.exe and
+mkbitmap.exe. You need to move these files to a place where Windows
+looks for programs, for example C:\WINDOWS. Alternatively, you can
+amend your PATH environment variable, by adding something like the
+following line to C:\AUTOEXEC.BAT:
+
+        PATH=%PATH%;C:\DIRECTORY\WHERE\FILES\ARE
+
+Note: as of version 1.6, the Potrace Windows distribution is built
+using MinGW and not Cygwin. It is no longer necessary to install a
+separate DLL file with Potrace.
+
+
+RUNNING:
+========
+
+For non-Windows specific usage information, see the file README.
+
+Potrace on Windows runs in much the same way as under Linux and other
+Unix-like operating systems. You must run Potrace from the command
+line (also known as the MSDOS Prompt). File names can be given in Unix
+style or Windows style, thus the following will both work:
+
+ potrace h:/data/file.txt
+ potrace h:\data\file.txt
+
+Wildcards can also be used, as in:
+
+ potrace h:\data\*.*
+ potrace h:/data/*.*
+
+Earlier versions of Potrace had some problems when wildcards and
+backslashes were mixed; these problems seem to have been solved by the
+switch from Cygwin to MinGW.
+
+Another problem that some users have reported is that the generated
+".ps" and ".eps" were not executable under Windows (i.e., one could
+not simply display these files by typing their name on the MSDOS
+Prompt, as should normally be the case if a default application for
+PostScript files has been configured). I was never able to replicate
+this problem, but I believe that it has also been solved by the switch
+to MinGW.
diff --git a/Build/source/libs/potrace/potrace-src/config.h.in b/Build/source/libs/potrace/potrace-src/config.h.in
new file mode 100644
index 00000000000..6dea9accfa9
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/config.h.in
@@ -0,0 +1,101 @@
+/* config.h.in.  Generated from configure.ac by autoheader.  */
+
+/* Use the simplified progress bar? */
+#undef DUMB_TTY
+
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#undef HAVE_DLFCN_H
+
+/* Does the C compiler have gcc bug 12243? */
+#undef HAVE_GCC_LOOP_BUG
+
+/* Can we use Intel 386 optimizations? */
+#undef HAVE_I386
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#undef HAVE_INTTYPES_H
+
+/* Define to 1 if you have the <memory.h> header file. */
+#undef HAVE_MEMORY_H
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#undef HAVE_STDINT_H
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#undef HAVE_STDLIB_H
+
+/* Define to 1 if you have the <strings.h> header file. */
+#undef HAVE_STRINGS_H
+
+/* Define to 1 if you have the <string.h> header file. */
+#undef HAVE_STRING_H
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#undef HAVE_SYS_STAT_H
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#undef HAVE_SYS_TYPES_H
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#undef HAVE_UNISTD_H
+
+/* Do we have the zlib library? */
+#undef HAVE_ZLIB
+
+/* Define to the sub-directory in which libtool stores uninstalled libraries.
+   */
+#undef LT_OBJDIR
+
+/* Name of the mkbitmap binary */
+#undef MKBITMAP
+
+/* Define if missing from math.h */
+#undef M_PI
+
+/* Name of package */
+#undef PACKAGE
+
+/* Define to the address where bug reports for this package should be sent. */
+#undef PACKAGE_BUGREPORT
+
+/* Define to the full name of this package. */
+#undef PACKAGE_NAME
+
+/* Define to the full name and version of this package. */
+#undef PACKAGE_STRING
+
+/* Define to the one symbol short name of this package. */
+#undef PACKAGE_TARNAME
+
+/* Define to the home page for this package. */
+#undef PACKAGE_URL
+
+/* Define to the version of this package. */
+#undef PACKAGE_VERSION
+
+/* Name of the potrace binary */
+#undef POTRACE
+
+/* Define to 1 if you have the ANSI C header files. */
+#undef STDC_HEADERS
+
+/* Use a4 papersize by default? */
+#undef USE_A4
+
+/* Use metric units by default? */
+#undef USE_METRIC
+
+/* Version number of package */
+#undef VERSION
+
+/* Define to `__inline__' or `__inline' if that's what the C compiler
+   calls it, or to nothing if 'inline' is not supported under any name.  */
+#ifndef __cplusplus
+#undef inline
+#endif
+
+/* Replacement function for strcasecmp */
+#undef strcasecmp
+
+/* Replacement function for strncasecmp */
+#undef strncasecmp
diff --git a/Build/source/libs/potrace/potrace-src/configure.ac b/Build/source/libs/potrace/potrace-src/configure.ac
new file mode 100644
index 00000000000..93be9b1c00d
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/configure.ac
@@ -0,0 +1,278 @@
+dnl Copyright (C) 2001-2015 Peter Selinger.
+dnl This file is part of Potrace. It is free software and it is covered
+dnl by the GNU General Public License. See the file COPYING for details.
+
+dnl Process this file with autoconf to produce a configure script.
+
+dnl ----------------------------------------------------------------------
+dnl Package info
+AC_INIT([potrace],[1.13],[selinger at users.sourceforge.net])
+AC_CONFIG_SRCDIR(src/trace.c)
+AM_INIT_AUTOMAKE
+AC_CONFIG_HEADER(config.h)
+AC_CONFIG_MACRO_DIR([m4])
+
+DATE="October 2015"
+
+dnl ----------------------------------------------------------------------
+dnl The names of the installed executables are defined here, but
+dnl should not normally be changed.
+
+POTRACE=potrace
+AC_DEFINE_UNQUOTED(POTRACE,"$POTRACE",Name of the potrace binary)
+
+MKBITMAP=mkbitmap
+AC_DEFINE_UNQUOTED(MKBITMAP,"$MKBITMAP",Name of the mkbitmap binary)
+
+dnl ----------------------------------------------------------------------
+dnl figure out compiler options
+
+dnl remember user's CFLAGS, if any
+iCFLAGS="$CFLAGS"
+
+dnl Check for compiler
+AC_PROG_CC
+
+dnl If compiler is gcc, add our own default CFLAGS if no others specified
+if test "$GCC" = "yes" && test "$iCFLAGS" = ""; then
+  CFLAGS="$CFLAGS -Wall -ffloat-store"
+fi
+
+dnl Also add CADD to the CFLAGS at configure time or compile time
+AC_SUBST(CADD)
+
+AC_MSG_CHECKING(what compiler options to use)
+AC_MSG_RESULT($CFLAGS $CADD)
+
+dnl ----------------------------------------------------------------------
+dnl check if --with-libpotrace was given - this must be done
+dnl before LT_INIT so that we can avoid building shared libraries
+dnl when they are not going to be installed.
+
+AC_ARG_WITH(libpotrace,
+ AS_HELP_STRING([--with-libpotrace],[install Potrace library and headers [default=no]]))
+
+if test "$with_libpotrace" != yes; then
+ enable_shared=no
+fi
+
+dnl ----------------------------------------------------------------------
+dnl Figure out how to build libraries
+
+AC_LIBTOOL_WIN32_DLL
+LT_INIT
+
+dnl ----------------------------------------------------------------------
+dnl Figure out whether to install libraries (default: no)
+
+AC_MSG_CHECKING(whether to install the Potrace library)
+if test "$with_libpotrace" = yes; then
+ AC_MSG_RESULT(yes)
+ INSTLIBS="libpotrace.la"
+ INSTHEADERS="potracelib.h"
+else
+ AC_MSG_RESULT(no)
+fi
+AC_SUBST(INSTLIBS)
+AC_SUBST(INSTHEADERS)
+
+dnl ----------------------------------------------------------------------
+dnl check for compiler bugs. 
+
+dnl The GCC compiler used to have a loop optimization bug that affected
+dnl potrace.  This bug had been present since gcc-2.X and was still
+dnl pending (as of gcc version 3.3.1). Since the presence of this bug
+dnl cannot be reliably tested, and I am not sure in which version it was
+dnl fixed, we simply assume (conservatively) that all gcc compilers may
+dnl have this bug. In future: add a test that checks the compiler
+dnl version.
+
+if test "$GCC" = "yes"; then 
+  AC_MSG_CHECKING([whether gcc has bug number 12243])
+  AC_DEFINE(HAVE_GCC_LOOP_BUG,, [Does the C compiler have gcc bug 12243?])
+  AC_MSG_RESULT(maybe)
+fi
+
+dnl ----------------------------------------------------------------------
+dnl check for features
+
+AC_MSG_CHECKING(whether to use zlib)
+AC_ARG_ENABLE(zlib,
+ AS_HELP_STRING([--disable-zlib],[disable PostScript level 3 compression]))
+if test "$enable_zlib" != no; then
+  AC_DEFINE(HAVE_ZLIB,, Do we have the zlib library?)
+  AC_MSG_RESULT(yes)
+else
+  AC_MSG_RESULT(no)
+fi
+
+dnl Set optional defaults
+AC_MSG_CHECKING(whether to default to metric units)
+AC_ARG_ENABLE(metric, 
+ AS_HELP_STRING([--enable-metric],[use metric units (centimeters) as default]))
+if test "$enable_metric" = yes; then
+  AC_DEFINE(USE_METRIC,, Use metric units by default?)
+  AC_MSG_RESULT(yes)
+else
+  AC_MSG_RESULT(no)
+fi
+
+AC_MSG_CHECKING(whether to default to a4 paper size)
+AC_ARG_ENABLE(a4, 
+ AS_HELP_STRING([--enable-a4],[use a4 as the default papersize]))
+if test "$enable_a4" = yes; then
+  AC_DEFINE(USE_A4,, Use a4 papersize by default?)
+  AC_MSG_RESULT(yes)
+else
+  AC_MSG_RESULT(no)
+fi
+
+AC_MSG_CHECKING(whether to use the simplified progress bar)
+AC_ARG_ENABLE(dumb-tty,
+ AS_HELP_STRING([--enable-dumb-tty], [use simplified ASCII-only progress bar]))
+dumb_tty="$enable_dumb_tty"
+if test -z "$dumb_tty"; then
+   AC_CANONICAL_HOST
+   if test "$host_os" = "mingw32"; then
+      dumb_tty="yes"
+   fi
+fi
+if test "$dumb_tty" = "yes"; then
+  AC_DEFINE(DUMB_TTY,, Use the simplified progress bar?)
+  AC_MSG_RESULT(yes)
+else
+  AC_MSG_RESULT(no)
+fi
+
+dnl ----------------------------------------------------------------------
+dnl Calculate value of "prefix", to aid guessing of include file and
+dnl library locations.
+
+USERPREFIX="$prefix"
+if test "$USERPREFIX" = "NONE"; then
+   USERPREFIX="$ac_default_prefix"
+fi
+
+dnl ----------------------------------------------------------------------
+dnl Check for header files
+
+if test "$enable_zlib" != no; then
+  AC_CHECK_HEADER(zlib.h, true,
+    [AC_MSG_WARN([zlib.h not found in standard location.
+Trying again with -I$USERPREFIX/include])
+    CPPFLAGS="$CPPFLAGS -I$USERPREFIX/include"
+    dnl need to unset cached value to repeat the test
+    unset ac_cv_header_zlib_h
+    AC_CHECK_HEADER(zlib.h, true, 
+      [AC_MSG_ERROR([cannot find zlib.h. 
+Rerun ./configure with CPPFLAGS=-I<include dir> if you have the header
+file in a non-standard directory, or with --disable-zlib to disable
+support for PostScript level 3 compression.])
+    ])
+  ])
+fi
+
+dnl ----------------------------------------------------------------------
+dnl Check for symbols
+AC_CHECK_DECL(M_PI, ,
+ AC_DEFINE(M_PI, 3.14159265358979323846, [Define if missing from math.h]),
+ [#include <math.h>])
+
+dnl ----------------------------------------------------------------------
+dnl Check for libraries
+
+if test "$enable_zlib" != no; then
+  AC_CHECK_LIB(z, deflate, EXTRA_LIBS="$EXTRA_LIBS -lz", 
+    [AC_MSG_WARN([libz library not found in standard location.
+Trying again with -L$USERPREFIX/lib])
+    LDFLAGS="$LDFLAGS -L$USERPREFIX/lib"
+    dnl need to unset cached value to repeat the test
+    unset ac_cv_lib_z_deflate
+    AC_CHECK_LIB(z, deflate, EXTRA_LIBS="$EXTRA_LIBS -lz",
+      [AC_MSG_ERROR([cannot find the libz library (-lz).
+Rerun ./configure with LDFLAGS=-L<lib dir> if you have the library in
+a non-standard directory, or with --disable-zlib to disable support
+for PostScript level 3 compression.])
+    ])
+  ])
+fi
+
+AC_CHECK_LIB(m, floor, true, AC_MSG_ERROR([cannot find the m library (-lm)]))
+
+dnl ----------------------------------------------------------------------
+dnl Check for library functions.
+
+dnl Check for getopt_long
+AC_CHECK_FUNC(getopt_long, have_getopt_long=yes, have_getopt_long=no)
+if test "$have_getopt_long" = "yes"; then
+   dnl Check whether getopt_long reorders its arguments
+   AC_MSG_CHECKING([whether getopt_long reorders its arguments])
+   AC_RUN_IFELSE([AC_LANG_PROGRAM(
+   [[ #include <getopt.h>
+      static struct option longopts[] = {
+        {"help", 0, 0, 'h'},
+	{0, 0, 0, 0}
+      };
+   ]], 
+   [[ int ac = 3;
+      char *av[] = { "main", "file", "-h" };
+      return 'h' == getopt_long(ac, av, "h", longopts, (int *)0) ? 0 : 1;
+   ]])], 
+   [AC_MSG_RESULT(yes)], 
+   [AC_MSG_RESULT(no)
+   have_getopt_long=no],
+   [AC_MSG_RESULT(maybe (cross-compiling))
+   have_getopt_long=no])
+fi
+if test "$have_getopt_long" != "yes"; then 
+   EXTRA_OBJS="$EXTRA_OBJS getopt.o getopt1.o"
+fi
+
+AC_CHECK_FUNC(strcasecmp, ,
+  [AC_CHECK_FUNC(stricmp, 
+    [AC_DEFINE_UNQUOTED(strcasecmp, stricmp, [Replacement function for strcasecmp])],
+    [AC_MSG_ERROR([cannot find a replacement for strcasecmp])]
+  )]
+)
+AC_CHECK_FUNC(strncasecmp, ,
+  [AC_CHECK_FUNC(strnicmp, 
+    [AC_DEFINE_UNQUOTED(strncasecmp, strnicmp, [Replacement function for strncasecmp])],
+    [AC_MSG_ERROR([cannot find a replacement for strncasecmp])]
+  )]
+)
+
+dnl ----------------------------------------------------------------------
+dnl Check whether we have i386 features
+AC_MSG_CHECKING([for Intel 386])
+AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]], [[int x;
+  asm("bsf %1,%0\njnz 0f\nmovl $32,%0\n0:":"=r"(x):"r"(x));
+  return x; /* need this so that -O2 does not optimize the asm away */
+]])],[AC_MSG_RESULT(yes) 
+ AC_DEFINE(HAVE_I386,, Can we use Intel 386 optimizations?)
+],[AC_MSG_RESULT(no)])	
+
+
+dnl ----------------------------------------------------------------------
+dnl Check whether compiler supports inlining
+
+AC_C_INLINE
+
+dnl ----------------------------------------------------------------------
+dnl Set up substitutions of non-standard configuration parameters
+AC_SUBST(DATE)
+AC_SUBST(POTRACE)
+AC_SUBST(MKBITMAP)
+AC_SUBST(EXTRA_OBJS)
+AC_SUBST(EXTRA_LIBS)
+AC_SUBST(AM_CPPFLAGS)
+AC_SUBST(POTRACELIB_VERSION)
+
+dnl ----------------------------------------------------------------------
+AC_CONFIG_FILES([Makefile 
+	   src/Makefile 
+	   doc/Makefile
+	   check/Makefile
+	   doc/potrace.1
+	   doc/mkbitmap.1
+          ])
+AC_OUTPUT
diff --git a/Build/source/libs/potrace/potrace-src/src/Makefile.am b/Build/source/libs/potrace/potrace-src/src/Makefile.am
new file mode 100644
index 00000000000..bf8431223b4
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/Makefile.am
@@ -0,0 +1,57 @@
+## Copyright (C) 2001-2015 Peter Selinger.
+## This file is part of Potrace. It is free software and it is covered
+## by the GNU General Public License. See the file COPYING for details.
+
+## Process this file with automake to produce Makefile.in
+
+AM_CFLAGS = $(CADD)
+
+#----------------------------------------------------------------------
+# programs:
+
+bin_PROGRAMS = potrace mkbitmap
+EXTRA_PROGRAMS = potracelib_demo
+
+potrace_SOURCES = main.c main.h bitmap_io.c bitmap_io.h backend_eps.c	\
+ backend_eps.h flate.c flate.h lists.h greymap.c greymap.h render.c	\
+ render.h backend_pgm.c backend_pgm.h backend_svg.c backend_svg.h	\
+ backend_xfig.c backend_xfig.h backend_dxf.c backend_dxf.h		\
+ backend_pdf.c backend_pdf.h backend_geojson.c backend_geojson.h	\
+ lzw.c lzw.h bitops.h auxiliary.h potracelib.h bitmap.h curve.h		\
+ platform.h progress.h progress_bar.c progress_bar.h bbox.c bbox.h	\
+ trans.c trans.h
+potrace_LDADD = libpotrace.la @EXTRA_OBJS@ -lm @EXTRA_LIBS@
+potrace_DEPENDENCIES = libpotrace.la @EXTRA_OBJS@
+
+mkbitmap_SOURCES = mkbitmap.c bitmap_io.c bitmap_io.h greymap.c	\
+ greymap.h platform.h bitmap.h potracelib.h bitops.h
+mkbitmap_LDADD = @EXTRA_OBJS@ -lm
+mkbitmap_DEPENDENCIES = @EXTRA_OBJS@
+
+potracelib_demo_SOURCES = potracelib_demo.c
+potracelib_demo_LDADD = libpotrace.la -lm
+potracelib_demo_DEPENDENCIES = libpotrace.la
+
+#----------------------------------------------------------------------
+# Potrace library:
+
+libsources = curve.c curve.h trace.c trace.h decompose.c		\
+ decompose.h potracelib.c potracelib.h lists.h auxiliary.h bitmap.h	\
+ progress.h
+
+lib_LTLIBRARIES = $(INSTLIBS)
+EXTRA_LTLIBRARIES = libpotrace.la
+libpotrace_la_SOURCES = $(libsources)
+libpotrace_la_LDFLAGS = -version-info 0:3:0 -rpath '$(libdir)' \
+ -export-symbols $(srcdir)/libpotrace-export.sym -no-undefined
+libpotrace_la_LIBADD = -lm
+MOSTLYCLEANFILES = libpotrace.la
+
+# header files to install
+include_HEADERS = $(INSTHEADERS)
+EXTRA_HEADERS = potracelib.h
+
+#----------------------------------------------------------------------
+# other stuff to distribute
+
+EXTRA_DIST = getopt.c getopt1.c getopt.h libpotrace-export.sym
diff --git a/Build/source/libs/potrace/potrace-src/src/auxiliary.h b/Build/source/libs/potrace/potrace-src/src/auxiliary.h
new file mode 100644
index 00000000000..b365a0b402b
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/auxiliary.h
@@ -0,0 +1,80 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* This header file collects some general-purpose macros (and static
+   inline functions) that are used in various places. */
+
+#ifndef AUXILIARY_H
+#define AUXILIARY_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+
+/* ---------------------------------------------------------------------- */
+/* point arithmetic */
+
+#include "potracelib.h"
+
+struct point_s {
+  long x;
+  long y;
+};
+typedef struct point_s point_t;
+
+typedef potrace_dpoint_t dpoint_t;
+
+/* convert point_t to dpoint_t */
+static inline dpoint_t dpoint(point_t p) {
+  dpoint_t res;
+  res.x = p.x;
+  res.y = p.y;
+  return res;
+}
+
+/* range over the straight line segment [a,b] when lambda ranges over [0,1] */
+static inline dpoint_t interval(double lambda, dpoint_t a, dpoint_t b) {
+  dpoint_t res;
+
+  res.x = a.x + lambda * (b.x - a.x);
+  res.y = a.y + lambda * (b.y - a.y);
+  return res;
+}
+
+/* ---------------------------------------------------------------------- */
+/* some useful macros. Note: the "mod" macro works correctly for
+   negative a. Also note that the test for a>=n, while redundant,
+   speeds up the mod function by 70% in the average case (significant
+   since the program spends about 16% of its time here - or 40%
+   without the test). The "floordiv" macro returns the largest integer
+   <= a/n, and again this works correctly for negative a, as long as
+   a,n are integers and n>0. */
+
+/* integer arithmetic */
+
+static inline int mod(int a, int n) {
+  return a>=n ? a%n : a>=0 ? a : n-1-(-1-a)%n;
+}
+
+static inline int floordiv(int a, int n) {
+  return a>=0 ? a/n : -1-(-1-a)/n;
+}
+
+/* Note: the following work for integers and other numeric types. */
+#undef sign
+#undef abs
+#undef min
+#undef max
+#undef sq
+#undef cu
+#define sign(x) ((x)>0 ? 1 : (x)<0 ? -1 : 0)
+#define abs(a) ((a)>0 ? (a) : -(a))
+#define min(a,b) ((a)<(b) ? (a) : (b))
+#define max(a,b) ((a)>(b) ? (a) : (b))
+#define sq(a) ((a)*(a))
+#define cu(a) ((a)*(a)*(a))
+
+#endif /* AUXILIARY_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_dxf.c b/Build/source/libs/potrace/potrace-src/src/backend_dxf.c
new file mode 100644
index 00000000000..39b12a9d76f
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_dxf.c
@@ -0,0 +1,278 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* The DXF backend of Potrace. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+
+#include "main.h"
+#include "backend_dxf.h"
+#include "potracelib.h"
+#include "lists.h"
+#include "auxiliary.h"
+#include "trans.h"
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary linear algebra functions */
+
+/* subtract two vectors */
+static dpoint_t sub(dpoint_t v, dpoint_t w) {
+  dpoint_t r;
+
+  r.x = v.x - w.x;
+  r.y = v.y - w.y;
+  return r;
+}
+
+/* inner product */
+static double iprod(dpoint_t v, dpoint_t w) {
+  return v.x * w.x + v.y * w.y;
+}
+
+/* cross product */
+static double xprod(dpoint_t v, dpoint_t w) {
+  return v.x * w.y - v.y * w.x;
+}
+
+/* calculate the DXF polyline "bulge" value corresponding to the angle
+   between two vectors. In case of "infinity" return 0.0. */
+static double bulge(dpoint_t v, dpoint_t w) {
+  double v2, w2, vw, vxw, nvw;
+
+  v2 = iprod(v, v);
+  w2 = iprod(w, w);
+  vw = iprod(v, w);
+  vxw = xprod(v, w);
+  nvw = sqrt(v2 * w2);
+
+  if (vxw == 0.0) {
+    return 0.0;
+  }    
+
+  return (nvw - vw) / vxw;
+}
+
+/* ---------------------------------------------------------------------- */
+/* DXF output synthesis */
+
+/* print with group code: the low-level DXF file format */
+static int ship(FILE *fout, int gc, const char *fmt, ...) {
+  va_list args;
+  int r;
+  int c;
+
+  r = fprintf(fout, "%3d\n", gc);
+  if (r < 0) {
+    return r;
+  }
+  c = r;
+  va_start(args, fmt);
+  r = vfprintf(fout, fmt, args);
+  va_end(args);
+  if (r < 0) {
+    return r;
+  }
+  c += r;
+  r = fprintf(fout, "\n");
+  if (r < 0) {
+    return r;
+  }
+  c += r;
+  return c;
+}
+
+/* output the start of a polyline */
+static void ship_polyline(FILE *fout, char *layer, int closed) {
+  ship(fout, 0, "POLYLINE");
+  ship(fout, 8, "%s", layer);
+  ship(fout, 66, "%d", 1);
+  ship(fout, 70, "%d", closed ? 1 : 0);
+}
+
+/* output a vertex */
+static void ship_vertex(FILE *fout, char *layer, dpoint_t v, double bulge) {
+  ship(fout, 0, "VERTEX");
+  ship(fout, 8, "%s", layer);
+  ship(fout, 10, "%f", v.x);
+  ship(fout, 20, "%f", v.y);
+  ship(fout, 42, "%f", bulge);
+}
+
+/* output the end of a polyline */
+static void ship_seqend(FILE *fout) {
+  ship(fout, 0, "SEQEND");
+}
+
+/* output a comment */
+static void ship_comment(FILE *fout, char *comment) {
+  ship(fout, 999, "%s", comment);
+}
+
+/* output the start of a section */
+static void ship_section(FILE *fout, char *name) {
+  ship(fout, 0, "SECTION");
+  ship(fout, 2, "%s", name);
+}
+
+static void ship_endsec(FILE *fout) {
+  ship(fout, 0, "ENDSEC");
+}
+
+static void ship_eof(FILE *fout) {
+  ship(fout, 0, "EOF");
+}
+
+/* ---------------------------------------------------------------------- */
+/* Simulated quadratic and bezier curves */
+
+/* Output vertices (with bulges) corresponding to a smooth pair of
+   circular arcs from A to B, tangent to AC at A and to CB at
+   B. Segments are meant to be concatenated, so don't output the final
+   vertex. */
+static void pseudo_quad(FILE *fout, char *layer, dpoint_t A, dpoint_t C, dpoint_t B) {
+  dpoint_t v, w;
+  double v2, w2, vw, vxw, nvw;
+  double a, b, c, y;
+  dpoint_t G;
+  double bulge1, bulge2;
+
+  v = sub(A, C);
+  w = sub(B, C);
+
+  v2 = iprod(v, v);
+  w2 = iprod(w, w);
+  vw = iprod(v, w);
+  vxw = xprod(v, w);
+  nvw = sqrt(v2 * w2);
+
+  a = v2 + 2*vw + w2;
+  b = v2 + 2*nvw + w2;
+  c = 4*nvw;
+  if (vxw == 0 || a == 0) {
+    goto degenerate;
+  }
+  /* assert: a,b,c >= 0, b*b - a*c >= 0, and 0 <= b - sqrt(b*b - a*c) <= a */
+  y = (b - sqrt(b*b - a*c)) / a;
+  G = interval(y, C, interval(0.5, A, B));
+
+  bulge1 = bulge(sub(A,G), v);
+  bulge2 = bulge(w, sub(B,G));
+
+  ship_vertex(fout, layer, A, -bulge1);
+  ship_vertex(fout, layer, G, -bulge2);
+  return;
+
+ degenerate:
+  ship_vertex(fout, layer, A, 0);
+
+  return;
+}
+
+/* produce a smooth from A to D, tangent to AB at A and to CD at D.
+   This is similar to a Bezier curve, except that our curve will be
+   made up of up to 4 circular arcs. This is particularly intended for
+   the case when AD and BC are parallel. Like arcs(), don't output the
+   final vertex. */
+static void pseudo_bezier(FILE *fout, char *layer, dpoint_t A, dpoint_t B, dpoint_t C, dpoint_t D) {
+  dpoint_t E = interval(0.75, A, B);
+  dpoint_t G = interval(0.75, D, C);
+  dpoint_t F = interval(0.5, E, G);
+
+  pseudo_quad(fout, layer, A, E, F);
+  pseudo_quad(fout, layer, F, G, D);
+  return;
+}
+
+/* ---------------------------------------------------------------------- */
+/* functions for converting a path to a DXF polyline */
+
+/* do one path. */
+static int dxf_path(FILE *fout, char *layer, potrace_curve_t *curve, trans_t t) {
+  int i;
+  dpoint_t *c, *c1;
+  int n = curve->n;
+
+  ship_polyline(fout, layer, 1);
+
+  for (i=0; i<n; i++) {
+    c = curve->c[i];
+    c1 = curve->c[mod(i-1,n)];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      ship_vertex(fout, layer, trans(c1[2], t), 0);
+      ship_vertex(fout, layer, trans(c[1], t), 0);
+      break;
+    case POTRACE_CURVETO:
+      pseudo_bezier(fout, layer, trans(c1[2], t), trans(c[0], t), trans(c[1], t), trans(c[2], t));
+      break;
+    }
+  }
+  ship_seqend(fout);
+  return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Backend. */
+
+/* public interface for DXF */
+int page_dxf(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+  potrace_path_t *p;
+  trans_t t;
+  char *layer = "0";
+
+  /* set up the coordinate transform (rotation) */
+  t.bb[0] = imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar;
+  t.bb[1] = imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar;
+  t.orig[0] = imginfo->trans.orig[0]+imginfo->lmar;
+  t.orig[1] = imginfo->trans.orig[1]+imginfo->bmar;
+  t.x[0] = imginfo->trans.x[0];
+  t.x[1] = imginfo->trans.x[1];
+  t.y[0] = imginfo->trans.y[0];
+  t.y[1] = imginfo->trans.y[1];
+
+  ship_comment(fout, "DXF data, created by "POTRACE" "VERSION", written by Peter Selinger 2001-2015");
+
+  /* header section */
+  ship_section(fout, "HEADER");
+
+  /* variables */
+  ship(fout, 9, "$ACADVER");
+  ship(fout, 1, "AC1006");
+  ship(fout, 9, "$EXTMIN");
+  ship(fout, 10, "%f", 0.0);
+  ship(fout, 20, "%f", 0.0);
+  ship(fout, 30, "%f", 0.0);
+  ship(fout, 9, "$EXTMAX");
+  ship(fout, 10, "%f", t.bb[0]);
+  ship(fout, 20, "%f", t.bb[1]);
+  ship(fout, 30, "%f", 0.0);
+
+  ship_endsec(fout);
+
+  /* entities section */
+  ship_section(fout, "ENTITIES");
+
+  /* write paths */
+  list_forall (p, plist) {
+    dxf_path(fout, layer, &p->curve, t);
+  }
+
+  ship_endsec(fout);
+  ship_eof(fout);
+
+  fflush(fout);
+  return 0;
+}
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_dxf.h b/Build/source/libs/potrace/potrace-src/src/backend_dxf.h
new file mode 100644
index 00000000000..37906a0eaf3
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_dxf.h
@@ -0,0 +1,15 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_DXF_H
+#define BACKEND_DXF_H
+
+#include "potracelib.h"
+#include "main.h"
+
+int page_dxf(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_DXF_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_eps.c b/Build/source/libs/potrace/potrace-src/src/backend_eps.c
new file mode 100644
index 00000000000..d992a1a2cf8
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_eps.c
@@ -0,0 +1,849 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* The Postscript backend of Potrace. This can produce "ps" or "eps"
+   output, and different kinds of graphical debugging
+   output. Postscript compression is optionally supplied via the
+   functions in flate.c. */
+
+#define _XOPEN_SOURCE 500
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+#include <stdlib.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "main.h"
+#include "backend_eps.h"
+#include "flate.h"
+#include "lists.h"
+#include "auxiliary.h"
+
+#define SAFE_CALLOC(var, n, typ) \
+  if ((var = (typ *)calloc(n, sizeof(typ))) == NULL) goto calloc_error 
+
+typedef int color_t;
+
+#define black  0x000000
+#define red    0xff0000
+#define green  0x008000
+#define blue   0x0000ff
+
+/* ---------------------------------------------------------------------- */
+/* functions for interfacing with compression backend */
+
+/* xship: callback function that must be initialized before calling
+   any other functions of the "ship" family. xship_file must be
+   initialized too. */
+
+/* print the token to f, but filtered through a compression
+   filter in case filter!=0 */
+static int (*xship)(FILE *f, int filter, char *s, int len);
+static FILE *xship_file;
+
+/* ship postscript code, filtered */
+static int ship(const char *fmt, ...) {
+  va_list args;
+  static char buf[4096]; /* static string limit is okay here because
+			    we only use constant format strings - for
+			    the same reason, it is okay to use
+			    vsprintf instead of vsnprintf below. */
+  va_start(args, fmt);
+  vsprintf(buf, fmt, args);
+  buf[4095] = 0;
+  va_end(args);
+
+  xship(xship_file, 1, buf, strlen(buf));
+  return 0;
+}  
+
+/* ship a postscript comment, unfiltered */
+static int shipcom(char *fmt, ...) {
+  static char buf[4096];
+  va_list args;
+
+  va_start(args, fmt);
+  vsprintf(buf, fmt, args);
+  buf[4095] = 0;
+  va_end(args);
+
+  xship(xship_file, 0, buf, strlen(buf));
+  return 0;
+}
+
+/* set all callback functions */
+static void eps_callbacks(FILE *fout) {
+  if (info.compress && info.pslevel==2) {
+    xship = lzw_xship;
+  } else if (info.compress && info.pslevel==3) {
+    xship = flate_xship;
+  } else {
+    xship = dummy_xship;
+  }
+  xship_file = fout;
+}  
+
+/* ---------------------------------------------------------------------- */
+/* postscript path-drawing auxiliary functions */
+
+/* coordinate quantization */
+static inline point_t unit(dpoint_t p) {
+  point_t q;
+
+  q.x = (long)(floor(p.x*info.unit+.5));
+  q.y = (long)(floor(p.y*info.unit+.5));
+  return q;
+}
+
+/* current point */
+static point_t cur;
+
+static void eps_coords(dpoint_t p) {
+  cur = unit(p);
+  ship("%ld %ld ", cur.x, cur.y);
+}
+
+static void eps_rcoords(dpoint_t p) {
+  point_t q;
+
+  q = unit(p);
+  ship("%ld %ld ", q.x-cur.x, q.y-cur.y);
+  cur = q;
+}
+
+static void eps_moveto(dpoint_t p) {
+  eps_coords(p);
+  ship("moveto\n");
+}
+
+/* move to point + offset */
+static void eps_moveto_offs(dpoint_t p, double xoffs, double yoffs) {
+  /* note: structs are passed by value, so the following assignment
+     does not modify the original struct in the caller */
+  p.x += xoffs;
+  p.y += yoffs;
+  eps_coords(p);
+  ship("moveto\n");
+}
+
+static void eps_lineto(dpoint_t p) {
+  eps_rcoords(p);
+  ship("rlineto\n");
+}
+
+static void eps_curveto(dpoint_t p1, dpoint_t p2, dpoint_t p3) {
+  point_t q1, q2, q3;
+
+  q1 = unit(p1);
+  q2 = unit(p2);
+  q3 = unit(p3);
+
+  ship("%ld %ld %ld %ld %ld %ld rcurveto\n", q1.x-cur.x, q1.y-cur.y, q2.x-cur.x, q2.y-cur.y, q3.x-cur.x, q3.y-cur.y);
+  
+  cur = q3;
+}
+
+/* this procedure returns a statically allocated string */
+static char *eps_colorstring(const color_t col) {
+  double r, g, b;
+  static char buf[100];
+
+  r = (col & 0xff0000) >> 16;
+  g = (col & 0x00ff00) >> 8;
+  b = (col & 0x0000ff) >> 0;
+
+  if (r==0 && g==0 && b==0) {
+    return "0 setgray";
+  } else if (r==255 && g==255 && b==255) {
+    return "1 setgray";
+  } else if (r == g && g == b) {
+    sprintf(buf, "%.3f setgray", r/255.0);
+    return buf;
+  } else {
+    sprintf(buf, "%.3f %.3f %.3f setrgbcolor", r/255.0, g/255.0, b/255.0);
+    return buf;
+  }
+}
+
+static color_t eps_color = -1;
+static double eps_width = -1;
+
+static void eps_setcolor(const color_t col) {
+  if (col == eps_color) {
+    return;
+  }
+  eps_color = col;
+
+  ship("%s\n", eps_colorstring(col));
+}
+
+static void eps_linewidth(double w) {
+  if (w == eps_width) {
+    return;
+  }
+  eps_width = w;
+  ship("%f setlinewidth\n", w * info.unit);
+}
+
+/* ---------------------------------------------------------------------- */
+/* functions for converting a path to postscript code */
+
+/* ---------------------------------------------------------------------- */
+/* ASCII encoding */
+
+/* explicit encoding, does not use special macros */
+static int eps_path_long(privcurve_t *curve) {
+  int i;
+  dpoint_t *c;
+  int m = curve->n;
+
+  c = curve->c[m-1];
+  eps_moveto(c[2]);
+
+  for (i=0; i<m; i++) {
+    c = curve->c[i];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      eps_lineto(c[1]);
+      eps_lineto(c[2]);
+      break;
+    case POTRACE_CURVETO:
+      eps_curveto(c[0], c[1], c[2]);
+      break;
+    }
+  }
+  return 0;
+}
+
+/* size-optimized encoding relies on special macros */
+static int eps_path_short(privcurve_t *curve) {
+  int i, i1;
+  long int *bq = NULL;  /* bq[m] */
+  long int *aq = NULL;  /* aq[m] */
+  point_t *v = NULL;    /* v[m] */
+  dpoint_t *q = NULL;   /* q[m] */
+  double M;
+  int m = curve->n;
+
+  SAFE_CALLOC(bq, m, long int);
+  SAFE_CALLOC(aq, m, long int);
+  SAFE_CALLOC(v, m, point_t);
+  SAFE_CALLOC(q, m, dpoint_t);
+
+  /* quantize vertices */
+  for (i=0; i<m; i++) {
+    v[i] = unit(curve->vertex[i]);
+  }
+
+  /* quantize beta */
+  for (i=0; i<m; i++) {
+    i1 = mod(i+1,m);
+    M = max(10, max(abs(v[i1].x-v[i].x), abs(v[i1].y-v[i].y)));
+    bq[i] = (int)(M * curve->beta[i] + 0.5);
+    if (curve->beta[i] != 0.5) {
+      q[i1] = interval(bq[i]/M, dpoint(v[i]), dpoint(v[i1]));
+    } else {
+      q[i1] = interval(0.5, dpoint(v[i]), dpoint(v[i1]));
+    }
+  }
+
+  /* quantize alpha */
+  for (i=0; i<m; i++) {
+    i1 = mod(i+1,m);
+    M = max(10, max(max(abs(q[i].x-v[i].x), abs(q[i].y-v[i].y)),
+		    max(abs(v[i].x-q[i1].x), abs(v[i].y-q[i1].y))));
+    if (curve->tag[i] == POTRACE_CURVETO) {
+      aq[i] = (int)(M * curve->alpha[i] + 0.5);
+      if (aq[i] > M) {
+	aq[i]--;
+      }
+    }
+  }
+
+  /* generate output */
+  ship("%ld %ld ", v[m-1].x, v[m-1].y);
+  ship("%ld %ld ", v[0].x - v[m-1].x, v[0].y - v[m-1].y);
+  if (curve->beta[m-1] == 0.5) {
+    ship("i\n");
+  } else {
+    ship("%ld I\n", bq[m-1]);
+  }
+  for (i=0; i<m; i++) {
+    if (i<m-1) {
+      ship("%ld %ld ", v[i+1].x - v[i].x, v[i+1].y - v[i].y);
+      if (curve->beta[i] != 0.5) {
+	ship("%ld ", bq[i]);
+      }
+    }
+    if (curve->tag[i] == POTRACE_CURVETO) {
+      ship(curve->beta[i] == 0.5 ? "%ld c\n" : "%ld C\n", aq[i]);
+    } else {
+      ship(curve->beta[i] == 0.5 ? "v\n" : "V\n");
+    }
+  }  
+
+  free(bq);
+  free(aq);
+  free(v);
+  free(q);
+  return 0;
+
+ calloc_error:
+  free(bq);
+  free(aq);
+  free(v);
+  free(q);
+  return 1;
+}
+
+static int eps_path(privcurve_t *curve) {
+  if (info.longcoding==0 && curve->alphacurve) {
+    return eps_path_short(curve);
+  } else {
+    return eps_path_long(curve);
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* functions for rendering various internal data structures, used to
+   generate debugging output */
+
+/* output jaggie curve in grey */
+static void eps_jaggy(potrace_path_t *plist) {
+  potrace_path_t *p;
+  int i;
+
+  ship(".9 setgray\n");
+  list_forall (p, plist) {
+    point_t *pt = p->priv->pt;
+    point_t cur, prev;
+
+    if (p->sign == '+') {
+      cur = prev = pt[p->priv->len-1];
+      eps_moveto(dpoint(cur));
+      for (i=0; i<p->priv->len; i++) {
+	if (pt[i].x != cur.x && pt[i].y != cur.y) {
+	  cur = prev;
+	  eps_lineto(dpoint(cur));
+	}
+	prev = pt[i];
+      }
+      eps_lineto(dpoint(pt[p->priv->len-1]));
+    } else {
+      cur = prev = pt[0];
+      eps_moveto(dpoint(cur));
+      for (i=p->priv->len-1; i>=0; i--) {
+	if (pt[i].x != cur.x && pt[i].y != cur.y) {
+          cur = prev;
+          eps_lineto(dpoint(cur));
+        }
+        prev = pt[i];
+      }
+      eps_lineto(dpoint(pt[0]));
+    }
+    if (p->next == NULL || p->next->sign == '+') {
+      ship("fill\n");
+    }
+  }
+}
+
+/* output polygon */
+static void eps_polygon(privcurve_t *curve, const color_t col) {
+  int i;
+  int m = curve->n;
+
+  eps_linewidth(.02);
+  eps_setcolor(col);
+  eps_moveto(curve->vertex[m-1]);
+  for (i=0; i<m; i++) {
+    eps_lineto(curve->vertex[i]);
+  }
+  ship("stroke\n");
+}
+
+/* output lines L and parameter alpha */
+static void eps_L(privcurve_t *curve, const color_t col) {
+  int i, i1;
+  double gamma;
+  dpoint_t p1, p4, p1l, p4l;
+  int m = curve->n;
+ 
+  for (i=0; i<m; i++) {
+    i1 = mod(i+1, m);
+    gamma = curve->alpha0[i1] * 0.75;
+    
+    p1 = curve->c[i][2];
+    p4 = curve->c[i1][2];
+    p1l = interval(gamma, p1, curve->vertex[i1]);
+    p4l = interval(gamma, p4, curve->vertex[i1]);
+    eps_linewidth(.02);
+    eps_setcolor(col);
+    eps_moveto(p1l);
+    eps_lineto(p4l);
+    ship("stroke\n");
+    eps_moveto_offs(curve->vertex[i1], -.4, -.4);
+    ship("times (%.2f) show\n", curve->alpha0[i1]);
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* postscript macros */
+
+/* special macros for size-optimized rendering of Bezier curves */
+static char *optimacros =
+  "/D{bind def}def\n"
+  "/R{roll}D\n"
+  "/K{copy}D\n"
+  "/P{pop}D\n"
+  "/p{3 2 R add 3 1 R add exch}D\n"
+  "/t{dup 4 3 R mul 3 1 R mul}D\n"
+  "/a{dup 1 sub neg 4 1 R t 5 2 R t p}D\n"
+  "/m{2 K le{exch}if P}D\n"
+  "/n{abs exch abs m}D\n"
+  "/d{-1 t p n}D\n"
+  "/s{[4 2 R] cvx def}D\n"
+  "/g{7 K P 4 K P P d 5 1 R d 10 m m div 5 K 12 8 R 5 4 R a 9 4 R 3 2 R a 6 4 R curveto}D\n"
+  "/e{4 2 R lineto lineto P P}D\n"
+  "/q{3 K P n 10 m div}D\n"
+  "/f{x y 7 4 R 5 1 R 4 K p /y s 7 2 R 2 K 9 7 R 7 6 R t p 2 K /x s}D\n"
+  "/C{4 1 R q f 7 6 R g}D\n"
+  "/V{q f e}D\n"
+  "/c{3 1 R .5 f 7 6 R g}D\n"
+  "/v{.5 f e}D\n"
+  "/j{5 K P p /y s 3 K t 7 5 R p /x s x moveto P}D\n"
+  "/i{.5 j}D\n"
+  "/I{dup 6 1 R q j 3 2 R}D\n"
+  "/z{closepath}D\n"
+  "/b{%s z fill}D\n"
+  "/w{%s z fill}D\n";
+
+/* special macros for debug output */
+static char *debugmacros =
+  "/unit { %f } def\n"
+  "/box { newpath 0 0 moveto 0 1 lineto 1 1 lineto 1 0 lineto closepath } def\n"
+  "/circ { newpath 0 0 1 0 360 arc closepath } def\n"
+  "/dot { gsave .15 mul dup scale circ fill grestore } def\n"
+  "/sq { gsave unit unit scale -.5 -.5 translate box .02 setlinewidth stroke grestore } def\n"
+  "/sq1 { gsave translate sq unit .6 mul dot grestore } def\n"
+  "/dot2 { gsave translate unit dot grestore } def\n"
+  "/usq { gsave unit unit scale -.5 -.5 rmoveto 0 1 rlineto 1 0 rlineto 0 -1 rlineto closepath .02 setlinewidth stroke grestore } def\n"
+  "/dot1 { gsave translate unit .3 mul dup scale circ fill grestore } def\n"
+  "/times { /Times-Roman findfont unit .3 mul scalefont setfont } def\n"
+  "/times1 { /Times-Roman findfont unit 10 mul scalefont setfont 0 0 0 setrgbcolor } def\n"
+  "/times2 { /Times-Roman findfont unit 2 mul scalefont setfont 0 0 0 setrgbcolor } def\n";
+
+/* ---------------------------------------------------------------------- */
+/* Backends for various types of output. */
+
+/* Normal output: black on transparent */
+static int render0(potrace_path_t *plist) {
+  potrace_path_t *p;
+
+  if (info.longcoding) {
+    eps_setcolor(info.color);
+    list_forall (p, plist) {
+      eps_path(p->priv->fcurve);
+      ship("closepath\n");
+      if (p->next == NULL || p->next->sign == '+') {
+	ship("fill\n");
+      }
+    }
+  } else {
+    list_forall (p, plist) {
+      eps_path(p->priv->fcurve);
+      if (p->next == NULL || p->next->sign == '+') {
+	ship("b\n");
+      } else {
+	ship("z\n");
+      }
+    }
+  }
+  return 0;
+}
+
+/* Opaque output: alternating black and white */
+static int render0_opaque(potrace_path_t *plist) {
+  potrace_path_t *p;
+  
+  if (info.longcoding) {
+    list_forall (p, plist) {
+      eps_path(p->priv->fcurve);
+      ship("closepath\n");
+      eps_setcolor(p->sign=='+' ? info.color : info.fillcolor);
+      ship("fill\n");
+    }
+  } else {
+    list_forall (p, plist) {
+      eps_path(p->priv->fcurve);
+      ship(p->sign=='+' ? "b\n" : "w\n");
+    }
+  }
+  return 0;
+}
+
+/* Debug output type 1 (show optimal polygon) */
+static int render1(potrace_path_t *plist) {
+  potrace_path_t *p;
+  int i;
+
+  eps_jaggy(plist);
+
+  list_forall (p, plist) {
+
+    point_t *pt = p->priv->pt;
+    int n = p->priv->len;
+    int m = p->priv->m;
+    int *po = p->priv->po;
+
+    eps_linewidth(.02);
+    eps_setcolor(black);
+    /* output jaggie curve in boxed style */
+    for (i=1; i<n; i++) {
+      eps_moveto(dpoint(pt[i-1]));
+      eps_lineto(dpoint(pt[i]));
+      ship("stroke\n");
+      eps_coords(dpoint(pt[i]));
+      ship("sq1\n");
+    }
+    eps_moveto(dpoint(pt[n-1]));
+    eps_lineto(dpoint(pt[0]));
+    ship("stroke\n");
+    eps_coords(dpoint(pt[0]));
+    ship("sq1\n");
+
+    /* output the uncorrected polygon */
+    eps_linewidth(.1);
+    eps_setcolor(blue);
+    eps_moveto(dpoint(pt[po[0]]));
+    for (i=1; i<m; i++) {
+      eps_lineto(dpoint(pt[po[i]]));
+    }
+    eps_lineto(dpoint(pt[po[0]]));
+    ship("stroke\n");
+    for (i=0; i<m; i++) {
+      eps_coords(dpoint(pt[po[i]]));
+      ship("dot2\n");
+    }
+  }
+  return 0;
+}
+
+/* Debug output type 2 (show corrected polygon and edge detection) */
+static int render2(potrace_path_t *plist) {
+  potrace_path_t *p;
+  int i;
+
+  /* output original bitmap in grey */
+  eps_jaggy(plist);
+  
+  list_forall (p, plist) {
+    /* output polygon with corrected edges, lines L, and parameter alpha */
+    eps_polygon(&p->priv->curve, black);
+    eps_L(&p->priv->curve, black);
+    
+    /* output the vertex unit squares */
+    for (i=0; i<p->priv->curve.n; i++) {
+      eps_moveto(p->priv->curve.vertex[i]);
+      ship("usq\n");
+    }
+
+    /* output the path */
+    eps_linewidth(.1);
+    eps_setcolor(blue);
+    eps_path(&p->priv->curve);
+    ship("closepath\n");
+    ship("stroke\n");
+
+    if (info.param->opticurve && info.debug == 3) {
+
+      /* output opticurve */
+      eps_linewidth(.05);
+      eps_setcolor(red);
+      eps_path(&p->priv->ocurve);
+      ship("closepath\n");
+      ship("stroke\n");
+      
+      /* output dots */
+      for (i=0; i<p->priv->ocurve.n; i++) {
+	eps_coords(p->priv->ocurve.c[i][2]);
+	ship("dot1\n");
+      }
+    }
+  }
+  return 0;
+}
+
+/* Free-style debug output */
+static int render_debug(potrace_path_t *plist) {
+  potrace_path_t *p;
+  int count;
+  int i;
+
+  /* output original bitmap in grey */
+  eps_jaggy(plist);
+
+  count = -1;
+  list_forall (p, plist) {
+    count++;
+
+    /* output path numbers */
+    eps_moveto_offs(p->priv->curve.vertex[0], 0, 5);
+    ship("times1 (%d) show\n", count);
+
+    /* output polygon with corrected edges, lines L, and parameter alpha */
+    eps_polygon(&p->priv->curve, black);
+    eps_L(&p->priv->curve, black);
+
+    /* output the vertex unit squares */
+    for (i=0; i<p->priv->curve.n; i++) {
+      eps_moveto(p->priv->curve.vertex[i]);
+      ship("usq\n");
+    }
+
+    /* output the vertex numbers */
+    for (i=0; i<p->priv->curve.n; i++) {
+      eps_moveto_offs(p->priv->curve.vertex[i], +1, +1);
+      ship("times2 (%d) show\n", i);
+    }
+    
+    /* output the path */
+    eps_linewidth(.1);
+    eps_setcolor(blue);
+    eps_path(&p->priv->curve);
+    ship("closepath\n");
+    ship("stroke\n");
+    
+    if (info.param->opticurve) {
+
+      /* output the opti-verteces polygon */
+      eps_polygon(&p->priv->ocurve, green);
+      
+      /* output opticurve */
+      eps_linewidth(.05);
+      eps_setcolor(red);
+      eps_path(&p->priv->ocurve);
+      ship("closepath\n");
+      ship("stroke\n");
+      
+      /* output dots */
+      for (i=0; i<p->priv->ocurve.n; i++) {
+	eps_coords(p->priv->ocurve.c[i][2]);
+	ship("dot1\n");
+      }
+
+      /* output beta parameters */
+      for (i=0; i<p->priv->ocurve.n; i++) {
+	eps_moveto_offs(p->priv->ocurve.c[i][2], +.4, -.4);
+	ship("times (%.2f) show\n", p->priv->ocurve.beta[i]);
+      }
+    }
+  }
+  return 0;
+}
+
+/* select the appropriate rendering function from above */
+static int eps_render(potrace_path_t *plist) {
+  int r;
+  
+  switch (info.debug) {
+  case 0:
+    if (info.opaque) {
+      r = render0_opaque(plist);
+    } else {
+      r = render0(plist);
+    }
+    break;
+  case 1:
+    r = render1(plist);
+    break;
+  case 2: case 3:
+    r = render2(plist);
+    break;
+  default:
+    r = render_debug(plist);
+    break;
+  }
+  return r;
+}  
+
+/* ---------------------------------------------------------------------- */
+/* EPS header and footer */
+
+static int eps_init(imginfo_t *imginfo) {
+  double origx = imginfo->trans.orig[0] + imginfo->lmar;
+  double origy = imginfo->trans.orig[1] + imginfo->bmar;
+  double scalex = imginfo->trans.scalex / info.unit;
+  double scaley = imginfo->trans.scaley / info.unit;
+  char *c0, *c1;
+
+  shipcom("%%!PS-Adobe-3.0 EPSF-3.0\n");
+  shipcom("%%%%Creator: "POTRACE" "VERSION", written by Peter Selinger 2001-2015\n");
+  shipcom("%%%%LanguageLevel: %d\n", info.pslevel);
+  shipcom("%%%%BoundingBox: 0 0 %.0f %.0f\n", 
+	  ceil(imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar),
+	  ceil(imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar));
+  shipcom("%%%%HiResBoundingBox: 0 0 %f %f\n", 
+	  imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar,
+	  imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar);
+  shipcom("%%%%Pages: 1\n");
+  shipcom("%%%%EndComments\n");
+  
+  shipcom("%%%%Page: 1 1\n");
+  ship("save\n");
+  if (!info.longcoding) {
+    c0 = strdup(eps_colorstring(info.color));
+    c1 = strdup(eps_colorstring(info.fillcolor));
+    if (!c0 || !c1) {
+      free(c0);
+      free(c1);
+      return 1;
+    }
+    ship(optimacros, c0, c1);
+    free(c0);
+    free(c1);
+  }
+  if (info.debug) {
+    ship(debugmacros, info.unit);
+  }
+  if (origx != 0 || origy != 0) {
+    ship("%f %f translate\n", origx, origy);
+  }
+  if (info.angle != 0) {
+    ship("%.2f rotate\n", info.angle);
+  }
+  ship("%f %f scale\n", scalex, scaley);
+
+  return 0;
+}
+
+static int eps_term(void) {
+  ship("restore\n");
+  shipcom("%%%%EOF\n");
+  return 0;
+}
+
+/* public interface for EPS */
+int page_eps(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+  int r;
+
+  eps_callbacks(fout);
+
+  eps_init(imginfo);
+  
+  r = eps_render(plist);
+  if (r) {
+    return r;
+  }
+
+  eps_term();
+
+  return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* PostScript header and footer */
+
+static int eps_pagenumber;
+
+int init_ps(FILE *fout) {
+  char *c0, *c1;
+
+  /* set callback functions for shipping routines */
+  eps_callbacks(fout);
+
+  shipcom("%%!PS-Adobe-3.0\n");
+  shipcom("%%%%Creator: "POTRACE" "VERSION", written by Peter Selinger 2001-2015\n");
+  shipcom("%%%%LanguageLevel: %d\n", info.pslevel);
+  shipcom("%%%%BoundingBox: 0 0 %d %d\n", info.paperwidth, info.paperheight);
+  shipcom("%%%%Pages: (atend)\n");
+  shipcom("%%%%EndComments\n");
+  if (!info.longcoding || info.debug) {
+    shipcom("%%%%BeginSetup\n");
+    if (!info.longcoding) {
+      c0 = strdup(eps_colorstring(info.color));
+      c1 = strdup(eps_colorstring(info.fillcolor));
+      if (!c0 || !c1) {
+	free(c0);
+	free(c1);
+	return 1;
+      }
+      ship(optimacros, c0, c1);
+      free(c0);
+      free(c1);
+    }
+    if (info.debug) {
+      ship(debugmacros, info.unit);
+    }
+    shipcom("%%%%EndSetup\n");
+  }
+  eps_pagenumber = 0;
+  fflush(fout);
+  return 0;
+}
+
+int term_ps(FILE *fout) {
+  eps_callbacks(fout);
+
+  shipcom("%%%%Trailer\n");
+  shipcom("%%%%Pages: %d\n", eps_pagenumber);
+  shipcom("%%%%EOF\n");
+  fflush(fout);
+
+  return 0;
+}
+
+static void eps_pageinit_ps(imginfo_t *imginfo) {
+  double origx = imginfo->trans.orig[0] + imginfo->lmar;
+  double origy = imginfo->trans.orig[1] + imginfo->bmar;
+  double scalex = imginfo->trans.scalex / info.unit;
+  double scaley = imginfo->trans.scaley / info.unit;
+
+  eps_pagenumber++;
+  eps_color = -1;
+  eps_width = -1;
+
+  shipcom("%%%%Page: %d %d\n", eps_pagenumber, eps_pagenumber);
+  ship("save\n");
+  if (origx != 0 || origy != 0) {
+    ship("%f %f translate\n", origx, origy);
+  }
+  if (info.angle != 0) {
+    ship("%.2f rotate\n", info.angle);
+  }
+  ship("%f %f scale\n", scalex, scaley);
+}
+
+static void eps_pageterm_ps(void) {
+  ship("restore\n");
+  ship("showpage\n");
+}
+
+int page_ps(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+  int r;
+
+  eps_callbacks(fout);
+
+  eps_pageinit_ps(imginfo);
+
+  r = eps_render(plist);
+  if (r) {
+    return r;
+  }
+
+  eps_pageterm_ps();
+
+  shipcom("");
+
+  fflush(fout);
+
+  return 0;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_eps.h b/Build/source/libs/potrace/potrace-src/src/backend_eps.h
new file mode 100644
index 00000000000..90c866622cb
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_eps.h
@@ -0,0 +1,19 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_EPS_H
+#define BACKEND_EPS_H
+
+#include "potracelib.h"
+#include "main.h"
+
+int init_ps(FILE *fout);
+int page_ps(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+int term_ps(FILE *fout);
+
+int page_eps(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_EPS_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_geojson.c b/Build/source/libs/potrace/potrace-src/src/backend_geojson.c
new file mode 100644
index 00000000000..d5318581f11
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_geojson.c
@@ -0,0 +1,223 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* The GeoJSON backend of Potrace. */
+/* Written 2012 by Christoph Hormann <chris_hormann@gmx.de> */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "main.h"
+#include "backend_geojson.h"
+#include "lists.h"
+#include "auxiliary.h"
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary */
+
+/* return a point on a 1-dimensional Bezier segment */
+static inline double bezier(double t, double x0, double x1, double x2, double x3) {
+  double s = 1-t;
+  return s*s*s*x0 + 3*(s*s*t)*x1 + 3*(t*t*s)*x2 + t*t*t*x3;
+}
+
+static char *format = "%f";
+
+/* Convert a floating-point number to a string, using a pre-determined
+   format. The format must be previously set with set_format().
+   Returns one of a small number of statically allocated strings. */
+static char *round_to_unit(double x) {
+  static int n = 0;
+  static char buf[4][100];
+
+  n++;
+  if (n >= 4) {
+    n = 0;
+  }
+  sprintf(buf[n], format, x);
+  return buf[n];
+}
+
+/* Select a print format for floating point numbers, appropriate for
+   the given scaling and info.unit. Note: the format must be so that
+   the resulting number fits into a buffer of size 100. */
+static void set_format(trans_t tr) {
+  double s;
+  int d;
+  static char buf[10];
+
+  s = min(fabs(tr.scalex), fabs(tr.scaley));
+  if (info.unit != 0.0 && s != 0.0) {
+    d = (int)ceil(log(info.unit/s) / log(10));
+  } else {
+    d = 0;
+  }
+  if (d <= 0) {
+    format = "%.0f";
+  } else if (d <= 20) {
+    sprintf(buf, "%%.%df", d);
+    format = buf;
+  } else {
+    format = "%e";
+  }  
+}
+
+/* ---------------------------------------------------------------------- */
+/* path-drawing auxiliary functions */
+
+static dpoint_t cur;
+
+static void geojson_moveto(FILE *fout, dpoint_t p, trans_t tr) {
+  dpoint_t q;
+
+  q = trans(p, tr);
+
+  fprintf(fout, "[%s, %s]", round_to_unit(q.x), round_to_unit(q.y));
+
+  cur = q;
+}
+
+static void geojson_lineto(FILE *fout, dpoint_t p, trans_t tr) {
+  dpoint_t q;
+
+  q = trans(p, tr);
+
+  fprintf(fout, ", [%s, %s]", round_to_unit(q.x), round_to_unit(q.y));
+
+  cur = q;
+}
+
+static void geojson_curveto(FILE *fout, dpoint_t p1, dpoint_t p2, dpoint_t p3, trans_t tr) {
+  dpoint_t q1;
+  dpoint_t q2;
+  dpoint_t q3;
+  double step, t;
+  int i;
+  double x, y;
+
+  q1 = trans(p1, tr);
+  q2 = trans(p2, tr);
+  q3 = trans(p3, tr);
+
+  step = 1.0 / 8.0;
+
+  for (i=0, t=step; i<8; i++, t+=step) {
+    x = bezier(t, cur.x, q1.x, q2.x, q3.x);
+    y = bezier(t, cur.y, q1.y, q2.y, q3.y);
+
+    fprintf(fout, ", [%s, %s]", round_to_unit(x), round_to_unit(y));
+  }
+
+  cur = q3;
+}
+
+/* ---------------------------------------------------------------------- */
+/* functions for converting a path to an SVG path element */
+
+static int geojson_path(FILE *fout, potrace_curve_t *curve, trans_t tr) {
+  int i;
+  dpoint_t *c;
+  int m = curve->n;
+
+  fprintf(fout, "      [");
+
+  c = curve->c[m-1];
+  geojson_moveto(fout, c[2], tr);
+
+  for (i=0; i<m; i++) {
+    c = curve->c[i];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      geojson_lineto(fout, c[1], tr);
+      geojson_lineto(fout, c[2], tr);
+      break;
+    case POTRACE_CURVETO:
+      geojson_curveto(fout, c[0], c[1], c[2], tr);
+      break;
+    }
+  }
+
+  fprintf(fout, " ]");
+
+  return 0;
+}
+
+
+static void write_polygons(FILE *fout, potrace_path_t *tree, trans_t tr, int first) {
+  potrace_path_t *p, *q;
+
+  for (p=tree; p; p=p->sibling) {
+
+    if (!first) fprintf(fout, ",\n");
+
+    fprintf(fout, "{ \"type\": \"Feature\",\n");
+    fprintf(fout, "  \"properties\": { },\n");
+    fprintf(fout, "  \"geometry\": {\n");
+    fprintf(fout, "    \"type\": \"Polygon\",\n");
+    fprintf(fout, "    \"coordinates\": [\n");
+
+    geojson_path(fout, &p->curve, tr);
+
+    for (q=p->childlist; q; q=q->sibling) {
+      fprintf(fout, ",\n");
+      geojson_path(fout, &q->curve, tr);
+    }
+
+    fprintf(fout, "    ]\n");
+    fprintf(fout, "  }\n");
+    fprintf(fout, "}");
+
+    for (q=p->childlist; q; q=q->sibling) {
+      write_polygons(fout, q->childlist, tr, 0);
+    }
+
+    first = 0;
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* Backend. */
+
+/* public interface for GeoJSON */
+int page_geojson(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+
+  trans_t tr;
+
+  /* set up the coordinate transform (rotation) */
+  tr.bb[0] = imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar;
+  tr.bb[1] = imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar;
+  tr.orig[0] = imginfo->trans.orig[0]+imginfo->lmar;
+  tr.orig[1] = imginfo->trans.orig[1]+imginfo->bmar;
+  tr.x[0] = imginfo->trans.x[0];
+  tr.x[1] = imginfo->trans.x[1];
+  tr.y[0] = imginfo->trans.y[0];
+  tr.y[1] = imginfo->trans.y[1];
+
+  /* set the print format for floating point numbers */
+  set_format(imginfo->trans);
+
+  /* header */
+  fprintf(fout, "{\n");
+  fprintf(fout, "\"type\": \"FeatureCollection\",\n");
+  fprintf(fout, "\"features\": [\n");
+
+  write_polygons(fout, plist, tr, 1);
+
+  /* write footer */
+  fprintf(fout, "\n]\n");
+  fprintf(fout, "}\n");
+
+  fflush(fout);
+
+  return 0;
+}
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_geojson.h b/Build/source/libs/potrace/potrace-src/src/backend_geojson.h
new file mode 100644
index 00000000000..985cc3c919e
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_geojson.h
@@ -0,0 +1,15 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_GEO_H
+#define BACKEND_GEO_H
+
+#include "potracelib.h"
+#include "main.h"
+
+int page_geojson(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_GEO_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_pdf.c b/Build/source/libs/potrace/potrace-src/src/backend_pdf.c
new file mode 100644
index 00000000000..f350557a853
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_pdf.c
@@ -0,0 +1,419 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* The PDF backend of Potrace. Stream compression is optionally
+	supplied via the functions in flate.c. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+#include <stdlib.h>
+
+#include "main.h"
+#include "backend_pdf.h"
+#include "flate.h"
+#include "lists.h"
+#include "potracelib.h"
+#include "auxiliary.h"
+
+typedef int color_t;
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary: growing arrays */
+
+struct intarray_s {
+  int size;
+  int *data;
+};
+typedef struct intarray_s intarray_t;
+
+static inline void intarray_init(intarray_t *ar) {
+  ar->size = 0;
+  ar->data = NULL;
+}
+
+static inline void intarray_term(intarray_t *ar) {
+  free(ar->data);
+  ar->size = 0;
+  ar->data = NULL;
+}
+
+/* Set ar[n]=val. Expects n>=0. Grows array if necessary. Return 0 on
+   success and -1 on error with errno set. */
+static inline int intarray_set(intarray_t *ar, int n, int val) {
+  int *p;
+  int s;
+
+  if (n >= ar->size) {
+    s = n+1024;
+    p = (int *)realloc(ar->data, s * sizeof(int));
+    if (!p) {
+      return -1;
+    }
+    ar->data = p;
+    ar->size = s;
+  }
+  ar->data[n] = val;
+  return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* some global variables */
+
+static intarray_t xref;
+static int nxref = 0;
+static intarray_t pages;
+static int npages;
+static int streamofs;
+static size_t outcount;  /* output file position */
+
+/* ---------------------------------------------------------------------- */
+/* functions for interfacing with compression backend */
+
+/* xship: callback function that must be initialized before calling
+   any other functions of the "ship" family. xship_file must be
+   initialized too. */
+
+/* print the token to f, but filtered through a compression
+   filter in case filter!=0 */
+static int (*xship)(FILE *f, int filter, char *s, int len);
+static FILE *xship_file;
+
+/* ship PDF code, filtered */
+static int ship(const char *fmt, ...) {
+  va_list args;
+  static char buf[4096]; /* static string limit is okay here because
+			    we only use constant format strings - for
+			    the same reason, it is okay to use
+			    vsprintf instead of vsnprintf below. */
+  va_start(args, fmt);
+  vsprintf(buf, fmt, args);
+  buf[4095] = 0;
+  va_end(args);
+
+  outcount += xship(xship_file, 1, buf, strlen(buf));
+  return 0;
+}  
+
+/* ship PDF code, unfiltered */
+static int shipclear(char *fmt, ...) {
+  static char buf[4096];
+  va_list args;
+
+  va_start(args, fmt);
+  vsprintf(buf, fmt, args);
+  buf[4095] = 0;
+  va_end(args);
+
+  outcount += xship(xship_file, 0, buf, strlen(buf));
+  return 0;
+}
+
+/* set all callback functions */
+static void pdf_callbacks(FILE *fout) {
+
+  if (info.compress) {
+    xship = pdf_xship;
+  } else {
+    xship = dummy_xship;
+  }
+  xship_file = fout;
+}  
+
+/* ---------------------------------------------------------------------- */
+/* PDF path-drawing auxiliary functions */
+
+/* coordinate quantization */
+static inline point_t unit(dpoint_t p) {
+  point_t q;
+
+  q.x = (long)(floor(p.x*info.unit+.5));
+  q.y = (long)(floor(p.y*info.unit+.5));
+  return q;
+}
+
+static void pdf_coords(dpoint_t p) {
+  point_t cur = unit(p);
+  ship("%ld %ld ", cur.x, cur.y);
+}
+
+static void pdf_moveto(dpoint_t p) {
+  pdf_coords(p);
+  ship("m\n");
+}
+
+static void pdf_lineto(dpoint_t p) {
+  pdf_coords(p);
+  ship("l\n");
+}
+
+static void pdf_curveto(dpoint_t p1, dpoint_t p2, dpoint_t p3) {
+  point_t q1, q2, q3;
+
+  q1 = unit(p1);
+  q2 = unit(p2);
+  q3 = unit(p3);
+
+  ship("%ld %ld %ld %ld %ld %ld c\n", q1.x, q1.y, q2.x, q2.y, q3.x, q3.y);
+}
+
+/* this procedure returns a statically allocated string */
+static char *pdf_colorstring(const color_t col) {
+  double r, g, b;
+  static char buf[100];
+
+  r = (col & 0xff0000) >> 16;
+  g = (col & 0x00ff00) >> 8;
+  b = (col & 0x0000ff) >> 0;
+
+  if (r==0 && g==0 && b==0) {
+    return "0 g";
+  } else if (r==255 && g==255 && b==255) {
+    return "1 g";
+  } else if (r == g && g == b) {
+    sprintf(buf, "%.3f g", r/255.0);
+    return buf;
+  } else {
+    sprintf(buf, "%.3f %.3f %.3f rg", r/255.0, g/255.0, b/255.0);
+    return buf;
+  }
+}
+
+static color_t pdf_color = -1;
+
+static void pdf_setcolor(const color_t col) {
+  if (col == pdf_color) {
+    return;
+  }
+  pdf_color = col;
+
+  ship("%s\n", pdf_colorstring(col));
+}
+
+/* explicit encoding, does not use special macros */
+static int pdf_path(potrace_curve_t *curve) {
+  int i;
+  dpoint_t *c;
+  int m = curve->n;
+
+  c = curve->c[m-1];
+  pdf_moveto(c[2]);
+
+  for (i=0; i<m; i++) {
+    c = curve->c[i];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      pdf_lineto(c[1]);
+      pdf_lineto(c[2]);
+      break;
+    case POTRACE_CURVETO:
+      pdf_curveto(c[0], c[1], c[2]);
+      break;
+    }
+  }
+  return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Backends for various types of output. */
+
+/* Normal output: black on transparent */
+static int render0(potrace_path_t *plist) {
+  potrace_path_t *p;
+
+  pdf_setcolor(info.color);
+  list_forall (p, plist) {
+    pdf_path(&p->curve);
+    ship("h\n");
+    if (p->next == NULL || p->next->sign == '+') {
+      ship("f\n");
+    }
+  }
+  return 0;
+}
+
+/* Opaque output: alternating black and white */
+static int render0_opaque(potrace_path_t *plist) {
+  potrace_path_t *p;
+  
+  list_forall (p, plist) {
+    pdf_path(&p->curve);
+    ship("h\n");
+    pdf_setcolor(p->sign=='+' ? info.color : info.fillcolor);
+    ship("f\n");
+  }
+  return 0;
+}
+
+/* select the appropriate rendering function from above */
+static int pdf_render(potrace_path_t *plist)
+{
+  if (info.opaque) {
+    return render0_opaque(plist);
+  }
+  return render0(plist);
+}  
+
+/* ---------------------------------------------------------------------- */
+/* PDF header and footer */
+
+int init_pdf(FILE *fout)
+{
+        intarray_init(&xref);
+	intarray_init(&pages);
+	nxref = 0;
+	npages = 0;
+
+	/* set callback functions for shipping routines */
+	pdf_callbacks(fout);
+	outcount = 0;
+
+	shipclear("%%PDF-1.3\n");
+
+	intarray_set(&xref, nxref++, outcount);
+	shipclear("1 0 obj\n<</Type/Catalog/Pages 3 0 R>>\nendobj\n");
+
+	intarray_set(&xref, nxref++, outcount);
+	shipclear("2 0 obj\n"
+		"<</Creator"
+		"("POTRACE" "VERSION", written by Peter Selinger 2001-2015)>>\n"
+		"endobj\n");
+
+	/* delay obj #3 (pages) until end */
+	nxref++;
+
+	fflush(fout);
+	return 0;
+}
+
+int term_pdf(FILE *fout)
+{
+	int startxref;
+	int i;
+
+	pdf_callbacks(fout);
+
+	intarray_set(&xref, 2, outcount);
+	shipclear("3 0 obj\n"
+		"<</Type/Pages/Count %d/Kids[\n", npages);
+	for (i = 0; i < npages; i++)
+		shipclear("%d 0 R\n", pages.data[i]);
+	shipclear("]>>\nendobj\n");
+
+	startxref = outcount;
+
+	shipclear("xref\n0 %d\n", nxref + 1);
+	shipclear("0000000000 65535 f \n");
+	for (i = 0; i < nxref; i++)
+		shipclear("%0.10d 00000 n \n", xref.data[i]);
+
+	shipclear("trailer\n<</Size %d/Root 1 0 R/Info 2 0 R>>\n", nxref + 1);
+	shipclear("startxref\n%d\n%%%%EOF\n", startxref);
+
+	fflush(fout);
+	intarray_term(&xref);
+	intarray_term(&pages);
+	return 0;
+}
+
+/* if largebbox is set, set bounding box to pagesize. */
+static void pdf_pageinit(imginfo_t *imginfo, int largebbox)
+{
+	double origx = imginfo->trans.orig[0] + imginfo->lmar;
+	double origy = imginfo->trans.orig[1] + imginfo->bmar;
+	double dxx = imginfo->trans.x[0] / info.unit;
+	double dxy = imginfo->trans.x[1] / info.unit;
+	double dyx = imginfo->trans.y[0] / info.unit;
+	double dyy = imginfo->trans.y[1] / info.unit;
+
+	double pagew = imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar;
+	double pageh = imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar;
+
+	pdf_color = -1;
+
+	intarray_set(&xref, nxref++, outcount);
+	shipclear("%d 0 obj\n", nxref);
+	shipclear("<</Type/Page/Parent 3 0 R/Resources<</ProcSet[/PDF]>>");
+	if (largebbox) {
+	  shipclear("/MediaBox[0 0 %d %d]", info.paperwidth, info.paperheight);
+	} else {
+	  shipclear("/MediaBox[0 0 %f %f]", pagew, pageh);
+	}
+	shipclear("/Contents %d 0 R>>\n", nxref + 1);
+	shipclear("endobj\n");
+
+	intarray_set(&pages, npages++, nxref);
+
+	intarray_set(&xref, nxref++, outcount);
+	shipclear("%d 0 obj\n", nxref);
+	if (info.compress)
+		shipclear("<</Filter/FlateDecode/Length %d 0 R>>\n", nxref + 1);
+	else
+		shipclear("<</Length %d 0 R>>\n", nxref + 1);
+	shipclear("stream\n");
+
+	streamofs = outcount;
+
+	ship("%f %f %f %f %f %f cm\n", dxx, dxy, dyx, dyy, origx, origy);
+}
+
+static void pdf_pageterm(void)
+{
+	int streamlen;
+
+	shipclear("");
+
+	streamlen = outcount - streamofs;
+	shipclear("endstream\nendobj\n");
+	
+	intarray_set(&xref, nxref++, outcount);
+	shipclear("%d 0 obj\n%d\nendobj\n", nxref, streamlen);
+}
+
+int page_pdf(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo)
+{
+  int r;
+
+  pdf_callbacks(fout);
+
+  pdf_pageinit(imginfo, 0);
+
+  r = pdf_render(plist);
+  if (r) {
+    return r;
+  }
+
+  pdf_pageterm();
+
+  fflush(fout);
+
+  return 0;
+}
+
+int page_pdfpage(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo)
+{
+  int r;
+
+  pdf_callbacks(fout);
+
+  pdf_pageinit(imginfo, 1);
+
+  r = pdf_render(plist);
+  if (r) {
+    return r;
+  }
+
+  pdf_pageterm();
+
+  fflush(fout);
+
+  return 0;
+}
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_pdf.h b/Build/source/libs/potrace/potrace-src/src/backend_pdf.h
new file mode 100644
index 00000000000..3bad72d4755
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_pdf.h
@@ -0,0 +1,20 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_PDF_H
+#define BACKEND_PDF_H
+
+#include "potracelib.h"
+#include "main.h"
+
+int init_pdf(FILE *fout);
+int page_pdf(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+int term_pdf(FILE *fout);
+
+int page_pdf(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+int page_pdfpage(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_PDF_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_pgm.c b/Build/source/libs/potrace/potrace-src/src/backend_pgm.c
new file mode 100644
index 00000000000..f6714258360
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_pgm.c
@@ -0,0 +1,106 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* The PGM backend of Potrace. Here we custom-render a set of Bezier
+   curves and output the result as a greymap. This is merely a
+   convenience, as the same could be achieved by piping the EPS output
+   through ghostscript. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <math.h>
+
+#include "backend_pgm.h"
+#include "potracelib.h"
+#include "lists.h"
+#include "greymap.h"
+#include "render.h"
+#include "main.h"
+#include "auxiliary.h"
+#include "trans.h"
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+static void pgm_path(potrace_curve_t *curve, trans_t t, render_t *rm) {
+  dpoint_t *c, c1[3];
+  int i;
+  int m = curve->n;
+  
+  c = curve->c[m-1];
+  c1[2] = trans(c[2], t);
+  render_moveto(rm, c1[2].x, c1[2].y);
+  
+  for (i=0; i<m; i++) {
+    c = curve->c[i];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      c1[1] = trans(c[1], t);
+      c1[2] = trans(c[2], t);
+      render_lineto(rm, c1[1].x, c1[1].y);
+      render_lineto(rm, c1[2].x, c1[2].y);
+      break;
+    case POTRACE_CURVETO:
+      c1[0] = trans(c[0], t);
+      c1[1] = trans(c[1], t);
+      c1[2] = trans(c[2], t);
+      render_curveto(rm, c1[0].x, c1[0].y, c1[1].x, c1[1].y, c1[2].x, c1[2].y);
+      break;
+    }
+  }
+}
+
+int page_pgm(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+  potrace_path_t *p;
+  greymap_t *gm;
+  render_t *rm;
+  int w, h;
+  trans_t t;
+  int mode;
+  char *comment = "created by "POTRACE" "VERSION", written by Peter Selinger 2001-2015";
+
+  t.bb[0] = imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar;
+  t.bb[1] = imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar;
+  t.orig[0] = imginfo->trans.orig[0]+imginfo->lmar;
+  t.orig[1] = imginfo->trans.orig[1]+imginfo->bmar;
+  t.x[0] = imginfo->trans.x[0];
+  t.x[1] = imginfo->trans.x[1];
+  t.y[0] = imginfo->trans.y[0];
+  t.y[1] = imginfo->trans.y[1];
+
+  w = (int)ceil(t.bb[0]);
+  h = (int)ceil(t.bb[1]);
+
+  gm = gm_new(w, h);
+  if (!gm) {
+    return 1;
+  }
+  rm = render_new(gm);
+  if (!rm) {
+    return 1;
+  }
+
+  gm_clear(gm, 255); /* white */
+
+  list_forall(p, plist) {
+    pgm_path(&p->curve, t, rm);
+  }
+
+  render_close(rm);
+
+  /* if negative orientation, make sure to invert effect of rendering */
+  mode = imginfo->width * imginfo->height < 0 ? GM_MODE_NEGATIVE : GM_MODE_POSITIVE;
+
+  gm_writepgm(fout, rm->gm, comment, 1, mode, info.gamma);
+
+  render_free(rm);
+  gm_free(gm);
+
+  return 0;
+}
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_pgm.h b/Build/source/libs/potrace/potrace-src/src/backend_pgm.h
new file mode 100644
index 00000000000..499e925b425
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_pgm.h
@@ -0,0 +1,16 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_PGM_H
+#define BACKEND_PGM_H
+
+#include <stdio.h>
+
+#include "potracelib.h"
+#include "main.h"
+
+int page_pgm(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_PGM_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_svg.c b/Build/source/libs/potrace/potrace-src/src/backend_svg.c
new file mode 100644
index 00000000000..4dd67c8934c
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_svg.c
@@ -0,0 +1,342 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* The SVG backend of Potrace. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "main.h"
+#include "backend_svg.h"
+#include "lists.h"
+#include "auxiliary.h"
+
+/* ---------------------------------------------------------------------- */
+/* path-drawing auxiliary functions */
+
+/* coordinate quantization */
+static inline point_t unit(dpoint_t p) {
+  point_t q;
+
+  q.x = (long)(floor(p.x*info.unit+.5));
+  q.y = (long)(floor(p.y*info.unit+.5));
+  return q;
+}
+
+static point_t cur;
+static char lastop = 0;
+static int column = 0;
+static int newline = 1;
+
+static void shiptoken(FILE *fout, char *token) {
+  int c = strlen(token);
+  if (!newline && column+c+1 > 75) {
+    fprintf(fout, "\n");
+    column = 0;
+    newline = 1;
+  } else if (!newline) {
+    fprintf(fout, " ");
+    column++;
+  }
+  fprintf(fout, "%s", token);
+  column += c;
+  newline = 0;
+}
+
+static void ship(FILE *fout, char *fmt, ...) {
+  va_list args;
+  static char buf[4096]; /* static string limit is okay here because
+			    we only use constant format strings - for
+			    the same reason, it is okay to use
+			    vsprintf instead of vsnprintf below. */
+  char *p, *q;
+
+  va_start(args, fmt);
+  vsprintf(buf, fmt, args);
+  buf[4095] = 0;
+  va_end(args);
+
+  p = buf;
+  while ((q = strchr(p, ' ')) != NULL) {
+    *q = 0;
+    shiptoken(fout, p);
+    p = q+1;
+  }
+  shiptoken(fout, p);
+}
+
+static void svg_moveto(FILE *fout, dpoint_t p) {
+  cur = unit(p);
+
+  ship(fout, "M%ld %ld", cur.x, cur.y);
+  lastop = 'M';
+}
+
+static void svg_rmoveto(FILE *fout, dpoint_t p) {
+  point_t q;
+
+  q = unit(p);
+  ship(fout, "m%ld %ld", q.x-cur.x, q.y-cur.y);
+  cur = q;
+  lastop = 'm';
+}
+
+static void svg_lineto(FILE *fout, dpoint_t p) {
+  point_t q;
+
+  q = unit(p);
+
+  if (lastop != 'l') {
+    ship(fout, "l%ld %ld", q.x-cur.x, q.y-cur.y);
+  } else {
+    ship(fout, "%ld %ld", q.x-cur.x, q.y-cur.y);
+  }
+  cur = q;
+  lastop = 'l';
+}
+
+static void svg_curveto(FILE *fout, dpoint_t p1, dpoint_t p2, dpoint_t p3) {
+  point_t q1, q2, q3;
+
+  q1 = unit(p1);
+  q2 = unit(p2);
+  q3 = unit(p3);
+
+  if (lastop != 'c') {
+    ship(fout, "c%ld %ld %ld %ld %ld %ld", q1.x-cur.x, q1.y-cur.y, q2.x-cur.x, q2.y-cur.y, q3.x-cur.x, q3.y-cur.y);
+  } else {
+    ship(fout, "%ld %ld %ld %ld %ld %ld", q1.x-cur.x, q1.y-cur.y, q2.x-cur.x, q2.y-cur.y, q3.x-cur.x, q3.y-cur.y);
+  }
+  cur = q3;
+  lastop = 'c';
+}
+
+/* ---------------------------------------------------------------------- */
+/* functions for converting a path to an SVG path element */
+
+/* Explicit encoding. If abs is set, move to first coordinate
+   absolutely. */
+static int svg_path(FILE *fout, potrace_curve_t *curve, int abs) {
+  int i;
+  dpoint_t *c;
+  int m = curve->n;
+
+  c = curve->c[m-1];
+  if (abs) {
+    svg_moveto(fout, c[2]);
+  } else {
+    svg_rmoveto(fout, c[2]);
+  }
+
+  for (i=0; i<m; i++) {
+    c = curve->c[i];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      svg_lineto(fout, c[1]);
+      svg_lineto(fout, c[2]);
+      break;
+    case POTRACE_CURVETO:
+      svg_curveto(fout, c[0], c[1], c[2]);
+      break;
+    }
+  }
+  newline = 1;
+  shiptoken(fout, "z");
+  return 0;
+}
+
+/* produce a jaggy path - for debugging. If abs is set, move to first
+   coordinate absolutely. If abs is not set, move to first coordinate
+   relatively, and traverse path in the opposite direction. */
+static int svg_jaggy_path(FILE *fout, point_t *pt, int n, int abs) {
+  int i;
+  point_t cur, prev;
+  
+  if (abs) {
+    cur = prev = pt[n-1];
+    svg_moveto(fout, dpoint(cur));
+    for (i=0; i<n; i++) {
+      if (pt[i].x != cur.x && pt[i].y != cur.y) {
+	cur = prev;
+	svg_lineto(fout, dpoint(cur));
+      }
+      prev = pt[i];
+    }
+    svg_lineto(fout, dpoint(pt[n-1]));
+  } else {
+    cur = prev = pt[0];
+    svg_rmoveto(fout, dpoint(cur));
+    for (i=n-1; i>=0; i--) {
+      if (pt[i].x != cur.x && pt[i].y != cur.y) {
+	cur = prev;
+	svg_lineto(fout, dpoint(cur));
+      }
+      prev = pt[i];
+    }
+    svg_lineto(fout, dpoint(pt[0]));
+  }
+  newline = 1;
+  shiptoken(fout, "z");
+  return 0;
+}
+
+static void write_paths_opaque(FILE *fout, potrace_path_t *tree) {
+  potrace_path_t *p, *q;
+
+  for (p=tree; p; p=p->sibling) {
+    if (info.grouping == 2) {
+      fprintf(fout, "<g>\n");
+      fprintf(fout, "<g>\n");
+    }
+    column = fprintf(fout, "<path fill=\"#%06x\" stroke=\"none\" d=\"", info.color);
+    newline = 1;
+    lastop = 0;
+    if (info.debug == 1) {
+      svg_jaggy_path(fout, p->priv->pt, p->priv->len, 1);
+    } else {
+      svg_path(fout, &p->curve, 1);
+    }
+    fprintf(fout, "\"/>\n");
+    for (q=p->childlist; q; q=q->sibling) {
+      column = fprintf(fout, "<path fill=\"#%06x\" stroke=\"none\" d=\"", info.fillcolor);
+      newline = 1;
+      lastop = 0;
+      if (info.debug == 1) {
+	svg_jaggy_path(fout, q->priv->pt, q->priv->len, 1);
+      } else {
+	svg_path(fout, &q->curve, 1);
+      }
+      fprintf(fout, "\"/>\n");
+    }
+    if (info.grouping == 2) {
+      fprintf(fout, "</g>\n");
+    }
+    for (q=p->childlist; q; q=q->sibling) {
+      write_paths_opaque(fout, q->childlist);
+    }
+    if (info.grouping == 2) {
+      fprintf(fout, "</g>\n");
+    }
+  }
+}
+
+static void write_paths_transparent_rec(FILE *fout, potrace_path_t *tree) {
+  potrace_path_t *p, *q;
+
+  for (p=tree; p; p=p->sibling) {
+    if (info.grouping == 2) {
+      fprintf(fout, "<g>\n");
+    }
+    if (info.grouping != 0) {
+      column = fprintf(fout, "<path d=\"");
+      newline = 1;
+      lastop = 0;
+    }
+    if (info.debug == 1) {
+      svg_jaggy_path(fout, p->priv->pt, p->priv->len, 1);
+    } else {
+      svg_path(fout, &p->curve, 1);
+    }
+    for (q=p->childlist; q; q=q->sibling) {
+      if (info.debug == 1) {
+	svg_jaggy_path(fout, q->priv->pt, q->priv->len, 0);
+      } else {
+	svg_path(fout, &q->curve, 0);
+      }
+    }
+    if (info.grouping != 0) {
+      fprintf(fout, "\"/>\n");
+    }
+    for (q=p->childlist; q; q=q->sibling) {
+      write_paths_transparent_rec(fout, q->childlist);
+    }
+    if (info.grouping == 2) {
+      fprintf(fout, "</g>\n");
+    }
+  }
+}
+
+static void write_paths_transparent(FILE *fout, potrace_path_t *tree) {
+  if (info.grouping == 0) {
+    column = fprintf(fout, "<path d=\"");
+    newline = 1;
+    lastop = 0;
+  }
+  write_paths_transparent_rec(fout, tree);
+  if (info.grouping == 0) {
+    fprintf(fout, "\"/>\n");
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* Backend. */
+
+/* public interface for SVG */
+int page_svg(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+
+  double bboxx = imginfo->trans.bb[0]+imginfo->lmar+imginfo->rmar;
+  double bboxy = imginfo->trans.bb[1]+imginfo->tmar+imginfo->bmar;
+  double origx = imginfo->trans.orig[0] + imginfo->lmar;
+  double origy = bboxy - imginfo->trans.orig[1] - imginfo->bmar;
+  double scalex = imginfo->trans.scalex / info.unit;
+  double scaley = -imginfo->trans.scaley / info.unit;
+
+  /* header */
+  fprintf(fout, "<?xml version=\"1.0\" standalone=\"no\"?>\n");
+  fprintf(fout, "<!DOCTYPE svg PUBLIC \"-//W3C//DTD SVG 20010904//EN\"\n");
+  fprintf(fout, " \"http://www.w3.org/TR/2001/REC-SVG-20010904/DTD/svg10.dtd\">\n");
+
+  /* set bounding box and namespace */
+  fprintf(fout, "<svg version=\"1.0\" xmlns=\"http://www.w3.org/2000/svg\"\n");
+  fprintf(fout, " width=\"%fpt\" height=\"%fpt\" viewBox=\"0 0 %f %f\"\n", 
+	  bboxx, bboxy, bboxx, bboxy);
+  fprintf(fout, " preserveAspectRatio=\"xMidYMid meet\">\n");
+
+  /* metadata: creator */
+  fprintf(fout, "<metadata>\n");
+  fprintf(fout, "Created by "POTRACE" "VERSION", written by Peter Selinger 2001-2015\n");
+  fprintf(fout, "</metadata>\n");
+
+  /* use a "group" tag to establish coordinate system and style */
+  fprintf(fout, "<g transform=\"");
+  if (origx != 0 || origy != 0) {
+    fprintf(fout, "translate(%f,%f) ", origx, origy);
+  }
+  if (info.angle != 0) {
+    fprintf(fout, "rotate(%.2f) ", -info.angle);
+  }
+  fprintf(fout, "scale(%f,%f)", scalex, scaley);
+  fprintf(fout, "\"\n");
+  fprintf(fout, "fill=\"#%06x\" stroke=\"none\">\n", info.color);
+
+  if (info.opaque) {
+    write_paths_opaque(fout, plist);
+  } else {
+    write_paths_transparent(fout, plist);
+  }
+
+  /* write footer */
+  fprintf(fout, "</g>\n");
+  fprintf(fout, "</svg>\n");
+  fflush(fout);
+
+  return 0;
+}
+
+/* the Gimppath backend is identical, except that it disables
+   --opaque, enables --flat, and the dimensions are pixel-based */
+int page_gimp(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+  info.opaque = 0;
+  info.grouping = 0;
+  return page_svg(fout, plist, imginfo);
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_svg.h b/Build/source/libs/potrace/potrace-src/src/backend_svg.h
new file mode 100644
index 00000000000..0bacb1c939e
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_svg.h
@@ -0,0 +1,16 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_SVG_H
+#define BACKEND_SVG_H
+
+#include "potracelib.h"
+#include "main.h"
+
+int page_svg(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+int page_gimp(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_SVG_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_xfig.c b/Build/source/libs/potrace/potrace-src/src/backend_xfig.c
new file mode 100644
index 00000000000..a4d2947229b
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_xfig.c
@@ -0,0 +1,252 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* The xfig backend of Potrace. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <string.h>
+#include <math.h>
+
+#include "main.h"
+#include "backend_xfig.h"
+#include "potracelib.h"
+#include "lists.h"
+#include "auxiliary.h"
+#include "trans.h"
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+struct pageformat_s {
+  char *name;
+  int w, h;
+};
+typedef struct pageformat_s pageformat_t;
+
+/* page formats known by xfig, and their dimensions in postscript points */
+static pageformat_t pageformat[] = {
+  { "A9",        105,  149 },
+  { "A8",        149,  211 },
+  { "A7",        211,  298 },
+  { "A6",        298,  421 },
+  { "A5",        421,  595 },
+  { "A4",        595,  842 },
+  { "A3",        842, 1191 },
+  { "A2",       1191, 1685 },
+  { "A1",       1685, 2383 },
+  { "A0",       2383, 3370 },
+
+  { "B10",        91,  129 },
+  { "B9",        129,  182 },
+  { "B8",        182,  258 },
+  { "B7",        258,  365 },
+  { "B6",        365,  516 },
+  { "B5",        516,  730 },
+  { "B4",        730, 1032 },
+  { "B3",       1032, 1460 },
+  { "B2",       1460, 2064 },
+  { "B1",       2064, 2920 },
+  { "B0",       2920, 4127 },
+
+  { "Letter",    612,  792 },
+  { "Legal",     612, 1008 },
+  { "Tabloid",   792, 1224 },
+  { "A",         612,  792 },
+  { "B",         792, 1224 },
+  { "C",        1224, 1584 },
+  { "D",        1584, 2448 },
+  { "E",        2448, 3168 },
+
+  { NULL, 0, 0 },
+};
+
+/* ---------------------------------------------------------------------- */
+/* path-drawing auxiliary functions */
+
+/* coordinate quantization */
+static inline point_t unit(dpoint_t p) {
+  point_t q;
+
+  q.x = (long)(floor(p.x+.5));
+  q.y = (long)(floor(p.y+.5));
+  return q;
+}
+
+static void xfig_point(FILE *fout, dpoint_t p, trans_t t) {
+  point_t q;
+
+  q = unit(trans(p, t));
+
+  fprintf(fout, "%ld %ld\n", q.x, q.y);
+}
+
+/* ---------------------------------------------------------------------- */
+/* functions for converting a path to a xfig */
+
+/* calculate number of xfig control points in this path */
+static int npoints(potrace_curve_t *curve, int m) {
+  int i;
+  int n=0;
+
+  for (i=0; i<m; i++) {
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      n += 1;
+      break;
+    case POTRACE_CURVETO:
+      n += 2;
+      break;
+    }
+  }
+  return n;
+}
+
+/* do one path. */
+static void xfig_path(FILE *fout, potrace_curve_t *curve, trans_t t, int sign, int depth) {
+  int i;
+  dpoint_t *c;
+  int m = curve->n;
+
+  fprintf(fout, "3 1 0 0 0 %d %d 0 20 0.000 0 0 0 %d\n", sign=='+' ? 32 : 33, depth, npoints(curve, m));
+
+  for (i=0; i<m; i++) {
+    c = curve->c[i];
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      xfig_point(fout, c[1], t);
+      break;
+    case POTRACE_CURVETO:
+      xfig_point(fout, c[0], t);
+      xfig_point(fout, c[1], t);
+      break;
+    }
+  }
+  for (i=0; i<m; i++) {
+    switch (curve->tag[i]) {
+    case POTRACE_CORNER:
+      fprintf(fout, "0\n");
+      break;
+    case POTRACE_CURVETO:
+      fprintf(fout, "1 1\n");
+      break;
+    }
+  }
+}
+
+/* render a whole tree */
+static void xfig_write_paths(FILE *fout, potrace_path_t *plist, trans_t t, int depth) {
+  potrace_path_t *p, *q;
+
+  for (p=plist; p; p=p->sibling) {
+    xfig_path(fout, &p->curve, t, p->sign, depth);
+    for (q=p->childlist; q; q=q->sibling) {
+      xfig_path(fout, &q->curve, t, q->sign, depth >= 1 ? depth-1 : 0);
+    }
+    for (q=p->childlist; q; q=q->sibling) {
+      xfig_write_paths(fout, q->childlist, t, depth >= 2 ? depth-2 : 0);
+    }
+  }
+}
+
+/* calculate the depth of a tree. Call with d=0. */
+static int xfig_get_depth(potrace_path_t *plist) {
+  potrace_path_t *p;
+  int max =0;
+  int d;
+
+  for (p=plist; p; p=p->sibling) {
+    d = xfig_get_depth(p->childlist);
+    if (d > max) {
+      max = d;
+    }
+  }
+  return max + 1;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Backend. */
+
+/* public interface for XFIG */
+int page_xfig(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo) {
+  trans_t t;
+  double origx = imginfo->trans.orig[0] + imginfo->lmar;
+  double origy = - imginfo->trans.orig[1] - imginfo->bmar + info.paperheight;
+  char *formatname;
+  int best, penalty;
+  pageformat_t *f;
+  int i;
+  int x0, y0, x1, y1;  /* in xfig's coordinates */
+  int depth;
+  
+  t.orig[0] = 1200/72.0 * origx;
+  t.orig[1] = 1200/72.0 * origy;
+  t.x[0] = 1200/72.0 * imginfo->trans.x[0];
+  t.x[1] = -1200/72.0 * imginfo->trans.x[1];
+  t.y[0] = 1200/72.0 * imginfo->trans.y[0];
+  t.y[1] = -1200/72.0 * imginfo->trans.y[1];
+
+  x0 = (int)(1200/72.0 * (origx - imginfo->trans.orig[0]));
+  y0 = (int)(1200/72.0 * (origy + imginfo->trans.orig[1]));
+  x1 = x0 + (int)(1200/72.0 * imginfo->trans.bb[0]);
+  y1 = y0 - (int)(1200/72.0 * imginfo->trans.bb[1]);
+
+  best = -1;
+  formatname = "Letter";
+
+  /* find closest page format */
+  for (i=0; pageformat[i].name; i++) {
+    f = &pageformat[i];
+    if (f->w >= info.paperwidth-1 && f->h >= info.paperheight-1) {
+      penalty = f->w + f->h;
+      if (best == -1 || penalty < best) {
+	best = penalty;
+	formatname = f->name;
+      }
+    }
+  }
+
+  /* header */
+  fprintf(fout, "#FIG 3.2\n");
+  fprintf(fout, "#created by "POTRACE" "VERSION", written by Peter Selinger 2001-2015\n");
+  fprintf(fout, "Portrait\n");
+  fprintf(fout, "Center\n");
+  fprintf(fout, "Inches\n");
+  fprintf(fout, "%s\n", formatname);
+  fprintf(fout, "100.0\n");
+  fprintf(fout, "Single\n");
+  fprintf(fout, "-2\n");
+  fprintf(fout, "1200 2\n");  /* 1200 pixels per inch */
+  fprintf(fout, "0 32 #%06x\n", info.color);
+  fprintf(fout, "0 33 #%06x\n", info.fillcolor);
+  fprintf(fout, "6 %d %d %d %d\n", x0-75, y1-35, x1+75, y0+35); /* bounding box */
+
+  /* determine depth of the tree */
+  depth = xfig_get_depth(plist);
+
+  /* figure out appropriate xfig starting depth. Note: xfig only has 1000 depths available */
+  if (depth <= 40) {
+    depth = 50;
+  } else if (depth < 990) {
+    depth += 10;
+  } else {
+    depth = 999;
+  }
+
+  /* write paths. Note: can never use "opticurve" with this backend -
+     it just does not approximate Bezier curves closely enough.  */
+  xfig_write_paths(fout, plist, t, depth);
+
+  fprintf(fout, "-6\n"); /* end bounding box */
+
+  fflush(fout);
+
+  return 0;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/backend_xfig.h b/Build/source/libs/potrace/potrace-src/src/backend_xfig.h
new file mode 100644
index 00000000000..b1d3af2b14e
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/backend_xfig.h
@@ -0,0 +1,15 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef BACKEND_XFIG_H
+#define BACKEND_XFIG_H
+
+#include "potracelib.h"
+#include "main.h"
+
+int page_xfig(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+
+#endif /* BACKEND_XFIG_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/bbox.c b/Build/source/libs/potrace/potrace-src/src/bbox.c
new file mode 100644
index 00000000000..27b16ebcb79
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/bbox.c
@@ -0,0 +1,154 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* figure out the true bounding box of a vector image */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <math.h>
+#include <stdlib.h>
+
+#include "bbox.h"
+#include "potracelib.h"
+#include "lists.h"
+
+/* ---------------------------------------------------------------------- */
+/* intervals */
+
+/* initialize the interval to [min, max] */
+static void interval(interval_t *i, double min, double max) {
+  i->min = min;
+  i->max = max;
+}
+
+/* initialize the interval to [x, x] */
+static inline void singleton(interval_t *i, double x) {
+  interval(i, x, x);
+}
+
+/* extend the interval to include the number x */
+static inline void extend(interval_t *i, double x) {
+  if (x < i->min) {
+    i->min = x;
+  } else if (x > i->max) {
+    i->max = x;
+  }
+}
+
+static inline int in_interval(interval_t *i, double x) {
+  return i->min <= x && x <= i->max;
+}
+
+/* ---------------------------------------------------------------------- */
+/* inner product */
+
+typedef potrace_dpoint_t dpoint_t;
+
+static double iprod(dpoint_t a, dpoint_t b) {
+  return a.x * b.x + a.y * b.y;
+}
+
+/* ---------------------------------------------------------------------- */
+/* linear Bezier segments */
+
+/* return a point on a 1-dimensional Bezier segment */
+static inline double bezier(double t, double x0, double x1, double x2, double x3) {
+  double s = 1-t;
+  return s*s*s*x0 + 3*(s*s*t)*x1 + 3*(t*t*s)*x2 + t*t*t*x3;
+}
+
+/* Extend the interval i to include the minimum and maximum of a
+   1-dimensional Bezier segment given by control points x0..x3. For
+   efficiency, x0 in i is assumed as a precondition. */
+static void bezier_limits(double x0, double x1, double x2, double x3, interval_t *i) {
+  double a, b, c, d, r;
+  double t, x;
+
+  /* the min and max of a cubic curve segment are attained at one of
+     at most 4 critical points: the 2 endpoints and at most 2 local
+     extrema. We don't check the first endpoint, because all our
+     curves are cyclic so it's more efficient not to check endpoints
+     twice. */
+
+  /* endpoint */
+  extend(i, x3);
+
+  /* optimization: don't bother calculating extrema if all control
+     points are already in i */
+  if (in_interval(i, x1) && in_interval(i, x2)) {
+    return;
+  }
+
+  /* solve for extrema. at^2 + bt + c = 0 */
+  a = -3*x0 + 9*x1 - 9*x2 + 3*x3;
+  b = 6*x0 - 12*x1 + 6*x2;
+  c = -3*x0 + 3*x1;
+  d = b*b - 4*a*c;
+  if (d > 0) {
+    r = sqrt(d);
+    t = (-b-r)/(2*a);
+    if (t > 0 && t < 1) {
+      x = bezier(t, x0, x1, x2, x3);
+      extend(i, x);
+    }
+    t = (-b+r)/(2*a);
+    if (t > 0 && t < 1) {
+      x = bezier(t, x0, x1, x2, x3);
+      extend(i, x);
+    }
+  }
+  return;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Potrace segments, curves, and pathlists */
+
+/* extend the interval i to include the inner product <v | dir> for
+   all points v on the segment. Assume precondition a in i. */
+static inline void segment_limits(int tag, dpoint_t a, dpoint_t c[3], dpoint_t dir, interval_t *i) {
+  switch (tag) {
+  case POTRACE_CORNER:
+    extend(i, iprod(c[1], dir));
+    extend(i, iprod(c[2], dir));
+    break;
+  case POTRACE_CURVETO:
+    bezier_limits(iprod(a, dir), iprod(c[0], dir), iprod(c[1], dir), iprod(c[2], dir), i);
+    break;
+  }
+}
+
+/* extend the interval i to include <v | dir> for all points v on the
+   curve. */
+static void curve_limits(potrace_curve_t *curve, dpoint_t dir, interval_t *i) {
+  int k;
+  int n = curve->n;
+
+  segment_limits(curve->tag[0], curve->c[n-1][2], curve->c[0], dir, i);
+  for (k=1; k<n; k++) {
+    segment_limits(curve->tag[k], curve->c[k-1][2], curve->c[k], dir, i);
+  }
+}
+
+/* compute the interval i to be the smallest interval including all <v
+   | dir> for points in the pathlist. If the pathlist is empty, return
+   the singleton interval [0,0]. */
+void path_limits(potrace_path_t *path, dpoint_t dir, interval_t *i) {
+  potrace_path_t *p;
+
+  /* empty image? */
+  if (path == NULL) {
+    interval(i, 0, 0);
+    return;
+  }
+
+  /* initialize interval to a point on the first curve */
+  singleton(i, iprod(path->curve.c[0][2], dir));
+
+  /* iterate */
+  list_forall(p, path) {
+    curve_limits(&p->curve, dir, i);
+  }
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/bbox.h b/Build/source/libs/potrace/potrace-src/src/bbox.h
new file mode 100644
index 00000000000..12e74626462
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/bbox.h
@@ -0,0 +1,18 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifndef BBOX_H
+#define BBOX_H
+
+#include "potracelib.h"
+
+/* an interval [min, max] */
+struct interval_s {
+  double min, max;
+};
+typedef struct interval_s interval_t;
+
+void path_limits(potrace_path_t *path, potrace_dpoint_t dir, interval_t *i);
+
+#endif /* BBOX_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/bitmap.h b/Build/source/libs/potrace/potrace-src/src/bitmap.h
new file mode 100644
index 00000000000..7b5a94bb161
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/bitmap.h
@@ -0,0 +1,113 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifndef BITMAP_H
+#define BITMAP_H
+
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <stddef.h>
+
+/* The bitmap type is defined in potracelib.h */
+#include "potracelib.h"
+
+/* The present file defines some convenient macros and static inline
+   functions for accessing bitmaps. Since they only produce inline
+   code, they can be conveniently shared by the library and frontends,
+   if desired */
+
+/* ---------------------------------------------------------------------- */
+/* some measurements */
+
+#define BM_WORDSIZE ((int)sizeof(potrace_word))
+#define BM_WORDBITS (8*BM_WORDSIZE)
+#define BM_HIBIT (((potrace_word)1)<<(BM_WORDBITS-1))
+#define BM_ALLBITS (~(potrace_word)0)
+
+/* macros for accessing pixel at index (x,y). U* macros omit the
+   bounds check. */
+
+#define bm_scanline(bm, y) ((bm)->map + (ptrdiff_t)(y)*(ptrdiff_t)(bm)->dy)
+#define bm_index(bm, x, y) (&bm_scanline(bm, y)[(x)/BM_WORDBITS])
+#define bm_mask(x) (BM_HIBIT >> ((x) & (BM_WORDBITS-1)))
+#define bm_range(x, a) ((int)(x) >= 0 && (int)(x) < (a))
+#define bm_safe(bm, x, y) (bm_range(x, (bm)->w) && bm_range(y, (bm)->h))
+#define BM_UGET(bm, x, y) ((*bm_index(bm, x, y) & bm_mask(x)) != 0)
+#define BM_USET(bm, x, y) (*bm_index(bm, x, y) |= bm_mask(x))
+#define BM_UCLR(bm, x, y) (*bm_index(bm, x, y) &= ~bm_mask(x))
+#define BM_UINV(bm, x, y) (*bm_index(bm, x, y) ^= bm_mask(x))
+#define BM_UPUT(bm, x, y, b) ((b) ? BM_USET(bm, x, y) : BM_UCLR(bm, x, y))
+#define BM_GET(bm, x, y) (bm_safe(bm, x, y) ? BM_UGET(bm, x, y) : 0)
+#define BM_SET(bm, x, y) (bm_safe(bm, x, y) ? BM_USET(bm, x, y) : 0)
+#define BM_CLR(bm, x, y) (bm_safe(bm, x, y) ? BM_UCLR(bm, x, y) : 0)
+#define BM_INV(bm, x, y) (bm_safe(bm, x, y) ? BM_UINV(bm, x, y) : 0)
+#define BM_PUT(bm, x, y, b) (bm_safe(bm, x, y) ? BM_UPUT(bm, x, y, b) : 0)
+
+/* free the given bitmap. Leaves errno untouched. */
+static inline void bm_free(potrace_bitmap_t *bm) {
+  if (bm) {
+    free(bm->map);
+  }
+  free(bm);
+}
+
+/* return new un-initialized bitmap. NULL with errno on error.
+   Assumes w, h >= 0. */
+static inline potrace_bitmap_t *bm_new(int w, int h) {
+  potrace_bitmap_t *bm;
+  int dy = w == 0 ? 0 : (w - 1) / BM_WORDBITS + 1;
+  ptrdiff_t size = (ptrdiff_t)dy * (ptrdiff_t)h * (ptrdiff_t)BM_WORDSIZE;
+
+  /* check for overflow error */
+  if (size < 0 || (h != 0 && dy != 0 && size / h / dy != BM_WORDSIZE)) {
+    errno = ENOMEM;
+    return NULL;
+  }
+
+  bm = (potrace_bitmap_t *) malloc(sizeof(potrace_bitmap_t));
+  if (!bm) {
+    return NULL;
+  }
+  bm->w = w;
+  bm->h = h;
+  bm->dy = dy;
+  bm->map = (potrace_word *) malloc(size);
+  if (!bm->map) {
+    free(bm);
+    return NULL;
+  }
+  return bm;
+}
+
+/* clear the given bitmap. Set all bits to c. */
+static inline void bm_clear(potrace_bitmap_t *bm, int c) {
+  /* Note: if the bitmap was created with bm_new, then it is
+     guaranteed that size will fit into the ptrdiff_t type. */
+  ptrdiff_t size = (ptrdiff_t)bm->dy * (ptrdiff_t)bm->h * (ptrdiff_t)BM_WORDSIZE;
+  memset(bm->map, c ? -1 : 0, size);
+}
+
+/* duplicate the given bitmap. Return NULL on error with errno set. */
+static inline potrace_bitmap_t *bm_dup(const potrace_bitmap_t *bm) {
+  potrace_bitmap_t *bm1 = bm_new(bm->w, bm->h);
+  ptrdiff_t size = (ptrdiff_t)bm->dy * (ptrdiff_t)bm->h * (ptrdiff_t)BM_WORDSIZE;
+  if (!bm1) {
+    return NULL;
+  }
+  memcpy(bm1->map, bm->map, size);
+  return bm1;
+}
+
+/* invert the given bitmap. */
+static inline void bm_invert(potrace_bitmap_t *bm) {
+  ptrdiff_t i;
+  ptrdiff_t size = (ptrdiff_t)bm->dy * (ptrdiff_t)bm->h;
+
+  for (i = 0; i < size; i++) {
+    bm->map[i] ^= BM_ALLBITS;
+  }
+}
+
+#endif /* BITMAP_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/bitmap_io.c b/Build/source/libs/potrace/potrace-src/src/bitmap_io.c
new file mode 100644
index 00000000000..8bbfe2dcdaa
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/bitmap_io.c
@@ -0,0 +1,847 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* Routines for manipulating bitmaps, including reading pbm files. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+
+#include "bitmap.h"
+#include "bitops.h"
+
+#define INTBITS (8*sizeof(int))
+
+static int bm_readbody_bmp(FILE *f, double threshold, potrace_bitmap_t **bmp);
+static int bm_readbody_pnm(FILE *f, double threshold, potrace_bitmap_t **bmp, int magic);
+
+/* ---------------------------------------------------------------------- */
+/* routines for reading pnm streams */
+
+/* read next character after whitespace and comments. Return EOF on
+   end of file or error. */
+static int fgetc_ws(FILE *f) {
+  int c;
+
+  while (1) {
+    c = fgetc(f);
+    if (c=='#') {
+      while (1) {
+	c = fgetc(f);
+	if (c=='\n' || c==EOF) {
+	  break;
+	}
+      }
+    }
+    /* space, tab, line feed, carriage return, form-feed */
+    if (c!=' ' && c!='\t' && c!='\r' && c!='\n' && c!=12) {
+      return c;
+    }
+  }
+}
+
+/* skip whitespace and comments, then read a non-negative decimal
+   number from a stream. Return -1 on EOF. Tolerate other errors (skip
+   bad characters). Do not the read any characters following the
+   number (put next character back into the stream) */
+
+static int readnum(FILE *f) {
+  int c;
+  int acc;
+
+  /* skip whitespace and comments */
+  while (1) {
+    c = fgetc_ws(f);
+    if (c==EOF) {
+      return -1;
+    }
+    if (c>='0' && c<='9') {
+      break;
+    }
+  }
+
+  /* first digit is already in c */
+  acc = c-'0';
+  while (1) {
+    c = fgetc(f);
+    if (c==EOF) {
+      break;
+    }
+    if (c<'0' || c>'9') {
+      ungetc(c, f);
+      break;
+    }
+    acc *= 10;
+    acc += c-'0';
+  }
+  return acc;
+}
+
+/* similar to readnum, but read only a single 0 or 1, and do not read
+   any characters after it. */
+
+static int readbit(FILE *f) {
+  int c;
+
+  /* skip whitespace and comments */
+  while (1) {
+    c = fgetc_ws(f);
+    if (c==EOF) {
+      return -1;
+    }
+    if (c>='0' && c<='1') {
+      break;
+    }
+  }
+
+  return c-'0';
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* read a PNM stream: P1-P6 format (see pnm(5)), or a BMP stream, and
+   convert the output to a bitmap. Return bitmap in *bmp. Return 0 on
+   success, -1 on error with errno set, -2 on bad file format (with
+   error message in bm_read_error), and 1 on premature end of file, -3
+   on empty file (including files which contain only whitespace and
+   comments), -4 if wrong magic number. If the return value is >=0,
+   *bmp is valid. */
+
+char *bm_read_error = NULL;
+
+int bm_read(FILE *f, double threshold, potrace_bitmap_t **bmp) {
+  int magic[2];
+
+  /* read magic number. We ignore whitespace and comments before the
+     magic, for the benefit of concatenated files in P1-P3 format.
+     Multiple P1-P3 images in a single file are not formally allowed
+     by the PNM standard, but there is no harm in being lenient. */
+
+  magic[0] = fgetc_ws(f);
+  if (magic[0] == EOF) {
+    return -3;
+  } 
+  magic[1] = fgetc(f);
+  if (magic[0] == 'P' && magic[1] >= '1' && magic[1] <= '6') {
+    return bm_readbody_pnm(f, threshold, bmp, magic[1]);
+  }
+  if (magic[0] == 'B' && magic[1] == 'M') {
+    return bm_readbody_bmp(f, threshold, bmp);
+  }
+  return -4;
+}
+
+/* ---------------------------------------------------------------------- */
+/* read PNM format */
+
+/* read PNM stream after magic number. Return values as for bm_read */
+static int bm_readbody_pnm(FILE *f, double threshold, potrace_bitmap_t **bmp, int magic) {
+  potrace_bitmap_t *bm;
+  int x, y, i, b, b1, sum;
+  int bpr; /* bytes per row (as opposed to 4*bm->c) */
+  int w, h, max;
+
+  bm = NULL;
+
+  w = readnum(f);
+  if (w<0) {
+    goto format_error;
+  }
+
+  h = readnum(f);
+  if (h<0) {
+    goto format_error;
+  }
+
+  /* allocate bitmap */
+  bm = bm_new(w, h);
+  if (!bm) {
+    return -1;
+  }
+
+  /* zero it out */
+  bm_clear(bm, 0);
+
+  switch (magic) {
+  default: 
+    /* not reached */
+    goto format_error;  
+
+  case '1':
+    /* read P1 format: PBM ascii */
+    
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+	b = readbit(f);
+	if (b<0) {
+	  goto eof;
+	}
+	BM_UPUT(bm, x, y, b);
+      }
+    }
+    break;
+
+  case '2':
+    /* read P2 format: PGM ascii */
+    
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+    
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+        b = readnum(f);
+        if (b<0) {
+          goto eof;
+        }
+        BM_UPUT(bm, x, y, b > threshold * max ? 0 : 1);
+      }
+    }
+    break;
+
+  case '3':
+    /* read P3 format: PPM ascii */
+    
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+    
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+	sum = 0;
+	for (i=0; i<3; i++) {
+	  b = readnum(f);
+	  if (b<0) {
+	    goto eof;
+	  }
+	  sum += b;
+	}
+        BM_UPUT(bm, x, y, sum > 3 * threshold * max ? 0 : 1);
+      }
+    }
+    break;
+
+  case '4':
+    /* read P4 format: PBM raw */
+
+    b = fgetc(f);  /* read single white-space character after height */
+    if (b==EOF) {
+      goto format_error;
+    }
+
+    bpr = (w+7)/8;
+
+    for (y=h-1; y>=0; y--) {
+      for (i=0; i<bpr; i++) {
+	b = fgetc(f);
+	if (b==EOF) {
+	  goto eof;
+	}
+	*bm_index(bm, i*8, y) |= ((potrace_word)b) << (8*(BM_WORDSIZE-1-(i % BM_WORDSIZE)));
+      }
+    }
+    break;
+
+  case '5':
+    /* read P5 format: PGM raw */
+
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+
+    b = fgetc(f);  /* read single white-space character after max */
+    if (b==EOF) {
+      goto format_error;
+    }
+
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+        b = fgetc(f);
+        if (b==EOF)
+          goto eof;
+        if (max>=256) {
+          b <<= 8;
+          b1 = fgetc(f);
+          if (b1==EOF)
+            goto eof;
+          b |= b1;
+        }
+        BM_UPUT(bm, x, y, b > threshold * max ? 0 : 1);
+      }
+    }
+    break;
+
+  case '6':
+    /* read P6 format: PPM raw */
+
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+
+    b = fgetc(f);  /* read single white-space character after max */
+    if (b==EOF) {
+      goto format_error;
+    }
+
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+        sum = 0;
+        for (i=0; i<3; i++) {
+          b = fgetc(f);
+          if (b==EOF) {
+            goto eof;
+	  }
+          if (max>=256) {
+            b <<= 8;
+            b1 = fgetc(f);
+            if (b1==EOF)
+              goto eof;
+            b |= b1;
+          }
+          sum += b;
+        }
+        BM_UPUT(bm, x, y, sum > 3 * threshold * max ? 0 : 1);
+      }
+    }
+    break;
+  }
+
+  *bmp = bm;
+  return 0;
+
+ eof:
+  *bmp = bm;
+  return 1;
+
+ format_error:
+  bm_free(bm);
+  if (magic == '1' || magic == '4') {
+    bm_read_error = "invalid pbm file";
+  } else if (magic == '2' || magic == '5') {
+    bm_read_error = "invalid pgm file";
+  } else {
+    bm_read_error = "invalid ppm file";
+  }
+  return -2;
+}
+
+/* ---------------------------------------------------------------------- */
+/* read BMP format */
+
+struct bmp_info_s {
+  unsigned int FileSize;
+  unsigned int reserved;
+  unsigned int DataOffset;
+  unsigned int InfoSize;
+  unsigned int w;              /* width */
+  unsigned int h;              /* height */
+  unsigned int Planes;
+  unsigned int bits;           /* bits per sample */
+  unsigned int comp;           /* compression mode */
+  unsigned int ImageSize;
+  unsigned int XpixelsPerM;
+  unsigned int YpixelsPerM;
+  unsigned int ncolors;        /* number of colors in palette */
+  unsigned int ColorsImportant;
+  unsigned int RedMask;
+  unsigned int GreenMask;
+  unsigned int BlueMask;
+  unsigned int AlphaMask;
+  unsigned int ctbits;         /* sample size for color table */
+  int topdown;                 /* top-down mode? */
+};
+typedef struct bmp_info_s bmp_info_t;
+
+/* auxiliary */
+
+static int bmp_count = 0; /* counter for byte padding */
+static int bmp_pos = 0;   /* counter from start of BMP data */
+
+/* read n-byte little-endian integer. Return 1 on EOF or error, else
+   0. Assume n<=4. */
+static int bmp_readint(FILE *f, int n, unsigned int *p) {
+  int i;
+  unsigned int sum = 0;
+  int b;
+
+  for (i=0; i<n; i++) {
+    b = fgetc(f);
+    if (b==EOF) {
+      return 1;
+    }
+    sum += b << (8*i);
+  }
+  bmp_count += n;
+  bmp_pos += n;
+  *p = sum;
+  return 0;
+}
+
+/* reset padding boundary */
+static void bmp_pad_reset(void) {
+  bmp_count = 0;
+}
+
+/* read padding bytes to 4-byte boundary. Return 1 on EOF or error,
+   else 0. */
+static int bmp_pad(FILE *f) {
+  int c, i, b;
+
+  c = (-bmp_count) & 3;
+  for (i=0; i<c; i++) {
+    b = fgetc(f);
+    if (b==EOF) {
+      return 1;
+    }
+  }
+  bmp_pos += c;
+  bmp_count = 0;
+  return 0;
+}
+  
+/* forward to the new file position. Return 1 on EOF or error, else 0 */
+static int bmp_forward(FILE *f, int pos) {
+  int b;
+
+  while (bmp_pos < pos) {
+    b = fgetc(f);
+    if (b==EOF) {
+      return 1;
+    }
+    bmp_pos++;
+    bmp_count++;
+  }
+  return 0;
+}
+
+#define TRY(x) if (x) goto try_error
+#define TRY_EOF(x) if (x) goto eof
+
+/* correct y-coordinate for top-down format */
+#define ycorr(y) (bmpinfo.topdown ? bmpinfo.h-1-y : y)
+
+/* safe colortable access */
+#define COLTABLE(c) ((c) < bmpinfo.ncolors ? coltable[(c)] : 0)
+
+/* read BMP stream after magic number. Return values as for bm_read.
+   We choose to be as permissive as possible, since there are many
+   programs out there which produce BMP. For instance, ppmtobmp can
+   produce codings with anywhere from 1-8 or 24 bits per sample,
+   although most specifications only allow 1,4,8,24,32. We can also
+   read both the old and new OS/2 BMP formats in addition to the
+   Windows BMP format. */
+static int bm_readbody_bmp(FILE *f, double threshold, potrace_bitmap_t **bmp) {
+  bmp_info_t bmpinfo;
+  int *coltable;
+  unsigned int b, c;
+  unsigned int i;
+  potrace_bitmap_t *bm;
+  int mask;
+  unsigned int x, y;
+  int col[2];
+  unsigned int bitbuf;
+  unsigned int n;
+  unsigned int redshift, greenshift, blueshift;
+  int col1[2];
+
+  bm_read_error = NULL;
+  bm = NULL;
+  coltable = NULL;
+
+  bmp_pos = 2;  /* set file position */
+
+  /* file header (minus magic number) */
+  TRY(bmp_readint(f, 4, &bmpinfo.FileSize));
+  TRY(bmp_readint(f, 4, &bmpinfo.reserved));
+  TRY(bmp_readint(f, 4, &bmpinfo.DataOffset));
+
+  /* info header */
+  TRY(bmp_readint(f, 4, &bmpinfo.InfoSize));
+  if (bmpinfo.InfoSize == 40 || bmpinfo.InfoSize == 64
+      || bmpinfo.InfoSize == 108 || bmpinfo.InfoSize == 124) {
+    /* Windows or new OS/2 format */
+    bmpinfo.ctbits = 32; /* sample size in color table */
+    TRY(bmp_readint(f, 4, &bmpinfo.w));
+    TRY(bmp_readint(f, 4, &bmpinfo.h));
+    TRY(bmp_readint(f, 2, &bmpinfo.Planes));
+    TRY(bmp_readint(f, 2, &bmpinfo.bits));
+    TRY(bmp_readint(f, 4, &bmpinfo.comp));
+    TRY(bmp_readint(f, 4, &bmpinfo.ImageSize));
+    TRY(bmp_readint(f, 4, &bmpinfo.XpixelsPerM));
+    TRY(bmp_readint(f, 4, &bmpinfo.YpixelsPerM));
+    TRY(bmp_readint(f, 4, &bmpinfo.ncolors));
+    TRY(bmp_readint(f, 4, &bmpinfo.ColorsImportant));
+    if (bmpinfo.InfoSize >= 108) { /* V4 and V5 bitmaps */
+      TRY(bmp_readint(f, 4, &bmpinfo.RedMask));
+      TRY(bmp_readint(f, 4, &bmpinfo.GreenMask));
+      TRY(bmp_readint(f, 4, &bmpinfo.BlueMask));
+      TRY(bmp_readint(f, 4, &bmpinfo.AlphaMask));
+    }
+    if (bmpinfo.w > 0x7fffffff) {
+      goto format_error;
+    }
+    if (bmpinfo.h > 0x7fffffff) {
+      bmpinfo.h = (-bmpinfo.h) & 0xffffffff;
+      bmpinfo.topdown = 1;
+    } else {
+      bmpinfo.topdown = 0;
+    }
+    if (bmpinfo.h > 0x7fffffff) {
+      goto format_error;
+    }
+  } else if (bmpinfo.InfoSize == 12) {
+    /* old OS/2 format */
+    bmpinfo.ctbits = 24; /* sample size in color table */
+    TRY(bmp_readint(f, 2, &bmpinfo.w));
+    TRY(bmp_readint(f, 2, &bmpinfo.h));
+    TRY(bmp_readint(f, 2, &bmpinfo.Planes));
+    TRY(bmp_readint(f, 2, &bmpinfo.bits));
+    bmpinfo.comp = 0;
+    bmpinfo.ncolors = 0;
+    bmpinfo.topdown = 0;
+  } else {
+    goto format_error;
+  }
+
+  if (bmpinfo.comp == 3 && bmpinfo.InfoSize < 108) {
+    /* bitfield feature is only understood with V4 and V5 format */
+    goto format_error;
+  }
+
+  if (bmpinfo.comp > 3 || bmpinfo.bits > 32) {
+    goto format_error;
+  }
+
+  /* forward to color table (e.g., if bmpinfo.InfoSize == 64) */
+  TRY(bmp_forward(f, 14+bmpinfo.InfoSize));
+
+  if (bmpinfo.Planes != 1) {
+    bm_read_error = "cannot handle bmp planes";
+    goto format_error;  /* can't handle planes */
+  }
+  
+  if (bmpinfo.ncolors == 0) {
+    bmpinfo.ncolors = 1 << bmpinfo.bits;
+  }
+
+  /* color table, present only if bmpinfo.bits <= 8. */
+  if (bmpinfo.bits <= 8) {
+    coltable = (int *) calloc(bmpinfo.ncolors, sizeof(int));
+    if (!coltable) {
+      goto std_error;
+    }
+    /* NOTE: since we are reading a bitmap, we can immediately convert
+       the color table entries to bits. */
+    for (i=0; i<bmpinfo.ncolors; i++) {
+      TRY(bmp_readint(f, bmpinfo.ctbits/8, &c));
+      c = ((c>>16) & 0xff) + ((c>>8) & 0xff) + (c & 0xff);
+      coltable[i] = (c > 3 * threshold * 255 ? 0 : 1);
+      if (i<2) {
+	col1[i] = c;
+      }
+    }
+  }
+
+  /* forward to data */
+  if (bmpinfo.InfoSize != 12) { /* not old OS/2 format */
+    TRY(bmp_forward(f, bmpinfo.DataOffset));
+  }
+
+  /* allocate bitmap */
+  bm = bm_new(bmpinfo.w, bmpinfo.h);
+  if (!bm) {
+    goto std_error;
+  }
+  
+  /* zero it out */
+  bm_clear(bm, 0);
+
+  switch (bmpinfo.bits + 0x100*bmpinfo.comp) {
+    
+  default:
+    goto format_error;
+    break;
+    
+  case 0x001:  /* monochrome palette */
+    if (col1[0] < col1[1]) { /* make the darker color black */
+      mask = 0xff;
+    } else {
+      mask = 0;
+    }
+    
+    /* raster data */
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      for (i=0; 8*i<bmpinfo.w; i++) {
+	TRY_EOF(bmp_readint(f, 1, &b));
+	b ^= mask;
+	*bm_index(bm, i*8, ycorr(y)) |= ((potrace_word)b) << (8*(BM_WORDSIZE-1-(i % BM_WORDSIZE)));
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+   
+  case 0x002:  /* 2-bit to 8-bit palettes */
+  case 0x003: 
+  case 0x004: 
+  case 0x005: 
+  case 0x006: 
+  case 0x007: 
+  case 0x008:
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      bitbuf = 0;  /* bit buffer: bits in buffer are high-aligned */
+      n = 0;       /* number of bits currently in bitbuffer */
+      for (x=0; x<bmpinfo.w; x++) {
+	if (n < bmpinfo.bits) {
+	  TRY_EOF(bmp_readint(f, 1, &b));
+	  bitbuf |= b << (INTBITS - 8 - n);
+	  n += 8;
+	}
+	b = bitbuf >> (INTBITS - bmpinfo.bits);
+	bitbuf <<= bmpinfo.bits;
+	n -= bmpinfo.bits;
+	BM_UPUT(bm, x, ycorr(y), COLTABLE(b));
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+
+  case 0x010:  /* 16-bit encoding */
+    /* can't do this format because it is not well-documented and I
+       don't have any samples */
+    bm_read_error = "cannot handle bmp 16-bit coding";
+    goto format_error;
+    break;
+
+  case 0x018:  /* 24-bit encoding */
+  case 0x020:  /* 32-bit encoding */
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      for (x=0; x<bmpinfo.w; x++) {
+        TRY_EOF(bmp_readint(f, bmpinfo.bits/8, &c));
+	c = ((c>>16) & 0xff) + ((c>>8) & 0xff) + (c & 0xff);
+        BM_UPUT(bm, x, ycorr(y), c > 3 * threshold * 255 ? 0 : 1);
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+
+  case 0x320:  /* 32-bit encoding with bitfields */
+    redshift = lobit(bmpinfo.RedMask);
+    greenshift = lobit(bmpinfo.GreenMask);
+    blueshift = lobit(bmpinfo.BlueMask);
+
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      for (x=0; x<bmpinfo.w; x++) {
+        TRY_EOF(bmp_readint(f, bmpinfo.bits/8, &c));
+	c = ((c & bmpinfo.RedMask) >> redshift) + ((c & bmpinfo.GreenMask) >> greenshift) + ((c & bmpinfo.BlueMask) >> blueshift);
+        BM_UPUT(bm, x, ycorr(y), c > 3 * threshold * 255 ? 0 : 1);
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+
+  case 0x204:  /* 4-bit runlength compressed encoding (RLE4) */
+    x = 0;
+    y = 0;
+
+    while (1) {
+      TRY_EOF(bmp_readint(f, 1, &b)); /* opcode */
+      TRY_EOF(bmp_readint(f, 1, &c)); /* argument */
+      if (b>0) {
+	/* repeat count */
+	col[0] = COLTABLE((c>>4) & 0xf);
+	col[1] = COLTABLE(c & 0xf);
+	for (i=0; i<b && x<bmpinfo.w; i++) {
+	  if (x>=bmpinfo.w) {
+	    x=0;
+	    y++;
+	  }
+	  if (y>=bmpinfo.h) {
+	    break;
+	  }
+	  BM_UPUT(bm, x, ycorr(y), col[i&1]);
+	  x++;
+	}
+      } else if (c == 0) {
+	/* end of line */
+	y++;
+	x = 0;
+      } else if (c == 1) {
+	/* end of bitmap */
+	break;
+      } else if (c == 2) {
+	/* "delta": skip pixels in x and y directions */
+	TRY_EOF(bmp_readint(f, 1, &b)); /* x offset */
+	TRY_EOF(bmp_readint(f, 1, &c)); /* y offset */
+	x += b;
+	y += c;
+      } else {
+	/* verbatim segment */
+	for (i=0; i<c; i++) {
+	  if ((i&1)==0) {
+	    TRY_EOF(bmp_readint(f, 1, &b));
+	  }
+	  if (x>=bmpinfo.w) {
+	    x=0;
+	    y++;
+	  }
+	  if (y>=bmpinfo.h) {
+	    break;
+	  }
+	  BM_PUT(bm, x, ycorr(y), COLTABLE((b>>(4-4*(i&1))) & 0xf));
+	  x++;
+	}
+	if ((c+1) & 2) {
+	  /* pad to 16-bit boundary */
+	  TRY_EOF(bmp_readint(f, 1, &b));
+	}
+      }
+    }
+    break;
+
+  case 0x108:  /* 8-bit runlength compressed encoding (RLE8) */
+    x = 0;
+    y = 0;
+    while (1) {
+      TRY_EOF(bmp_readint(f, 1, &b)); /* opcode */
+      TRY_EOF(bmp_readint(f, 1, &c)); /* argument */
+      if (b>0) {
+	/* repeat count */
+	for (i=0; i<b; i++) {
+	  if (x>=bmpinfo.w) {
+	    x=0;
+	    y++;
+	  }
+	  if (y>=bmpinfo.h) {
+	    break;
+	  }
+	  BM_UPUT(bm, x, ycorr(y), COLTABLE(c));
+	  x++;
+	}
+      } else if (c == 0) {
+	/* end of line */
+	y++;
+	x = 0;
+      } else if (c == 1) {
+	/* end of bitmap */
+	break;
+      } else if (c == 2) {
+	/* "delta": skip pixels in x and y directions */
+	TRY_EOF(bmp_readint(f, 1, &b)); /* x offset */
+	TRY_EOF(bmp_readint(f, 1, &c)); /* y offset */
+	x += b;
+	y += c;
+      } else {
+	/* verbatim segment */
+	for (i=0; i<c; i++) {
+	  TRY_EOF(bmp_readint(f, 1, &b));
+          if (x>=bmpinfo.w) {
+            x=0;
+            y++;
+          }
+          if (y>=bmpinfo.h) {
+            break;
+          }
+	  BM_PUT(bm, x, ycorr(y), COLTABLE(b));
+	  x++;
+	}
+	if (c & 1) {
+	  /* pad input to 16-bit boundary */
+	  TRY_EOF(bmp_readint(f, 1, &b));
+	}
+      }
+    }
+    break;
+
+  } /* switch */
+
+  /* skip any potential junk after the data section, but don't
+     complain in case EOF is encountered */
+  bmp_forward(f, bmpinfo.FileSize);
+
+  free(coltable);
+  *bmp = bm;
+  return 0;
+
+ eof:
+  free(coltable);
+  *bmp = bm;
+  return 1;
+
+ format_error:
+ try_error:
+  free(coltable);
+  bm_free(bm);
+  if (!bm_read_error) {
+    bm_read_error = "invalid bmp file";
+  }
+  return -2;
+
+ std_error:
+  free(coltable);
+  bm_free(bm);
+  return -1;
+}
+
+/* ---------------------------------------------------------------------- */
+/* output pbm format */
+
+void bm_writepbm(FILE *f, potrace_bitmap_t *bm) {
+  int w, h, bpr, y, i, c;
+
+  w = bm->w;
+  h = bm->h;
+
+  bpr = (w+7)/8;
+
+  fprintf(f, "P4\n%d %d\n", w, h);
+  for (y=h-1; y>=0; y--) {
+    for (i=0; i<bpr; i++) {
+      c = (*bm_index(bm, i*8, y) >> (8*(BM_WORDSIZE-1-(i % BM_WORDSIZE)))) & 0xff;
+      fputc(c, f);
+    }
+  }
+  return;
+}
+
+/* ---------------------------------------------------------------------- */
+/* output - for primitive debugging purposes only! */
+
+/* print bitmap to screen */
+int bm_print(FILE *f, potrace_bitmap_t *bm) {
+  int x, y;
+  int xx, yy;
+  int d;
+  int sw, sh;
+
+  sw = bm->w < 79 ? bm->w : 79;
+  sh = bm->w < 79 ? bm->h : bm->h*sw*44/(79*bm->w);
+
+  for (yy=sh-1; yy>=0; yy--) {
+    for (xx=0; xx<sw; xx++) {
+      d=0;
+      for (x=xx*bm->w/sw; x<(xx+1)*bm->w/sw; x++) {
+	for (y=yy*bm->h/sh; y<(yy+1)*bm->h/sh; y++) {
+	  if (BM_GET(bm, x, y)) {
+	    d++;
+	  }
+	}
+      }
+      fputc(d ? '*' : ' ', f);
+    }
+    fputc('\n', f);
+  }
+  return 0;
+}
+
diff --git a/Build/source/libs/potrace/potrace-src/src/bitmap_io.h b/Build/source/libs/potrace/potrace-src/src/bitmap_io.h
new file mode 100644
index 00000000000..04b1c9ca1d2
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/bitmap_io.h
@@ -0,0 +1,23 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* bitmap input/output functions */
+
+#ifndef BITMAP_IO_H
+#define BITMAP_IO_H
+
+#include <stdio.h>
+#include "bitmap.h"
+
+/* Note that bitmaps are stored bottom to top, i.e., the first
+   scanline is the bottom-most one */
+
+extern char *bm_read_error;
+
+int bm_read(FILE *f, double blacklevel, potrace_bitmap_t **bmp);
+void bm_writepbm(FILE *f, potrace_bitmap_t *bm);
+int bm_print(FILE *f, potrace_bitmap_t *bm);
+
+#endif /* BITMAP_IO_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/bitops.h b/Build/source/libs/potrace/potrace-src/src/bitops.h
new file mode 100644
index 00000000000..ba84b53269b
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/bitops.h
@@ -0,0 +1,83 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* bits.h: this file defines some macros for bit manipulations. We
+   provide a generic implementation, as well as machine- and
+   compiler-specific fast implementations */
+
+/* lobit: return the position of the rightmost "1" bit of an int, or
+   32 if none. hibit: return 1 + the position of the leftmost "1" bit
+   of an int, or 0 if none. Note: these functions work on 32-bit
+   integers. */
+
+#ifndef BITOPS_H
+#define BITOPS_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+/* ---------------------------------------------------------------------- */
+/* machine specific macros */
+
+#if defined(HAVE_I386)
+
+static inline unsigned int lobit(unsigned int x) {
+  unsigned int res;
+  asm ("bsf	%1,%0\n\t"
+       "jnz	0f\n\t"
+       "movl	$32,%0\n"
+       "0:"
+       : "=r" (res)
+       : "r" (x)
+       : "cc");
+  return res;
+}
+
+static inline unsigned int hibit(unsigned int x) {
+  unsigned int res;					
+
+  asm ("bsr	%1,%0\n\t"
+       "jnz	0f\n\t"
+       "movl	$-1,%0\n"
+       "0:"
+       : "=r" (res)
+       : "r" (x)
+       : "cc");
+  return res+1;
+}
+
+/* ---------------------------------------------------------------------- */
+#else /* generic macros */
+
+static inline unsigned int lobit(unsigned int x) {
+  unsigned int res = 32;
+  while (x & 0xffffff) {
+    x <<= 8;
+    res -= 8;
+  }
+  while (x) {
+    x <<= 1;
+    res -= 1;
+  }
+  return res;
+}
+
+static inline unsigned int hibit(unsigned int x) {
+  unsigned int res = 0;
+  while (x > 0xff) {
+    x >>= 8;
+    res += 8;
+  }
+  while (x) {
+    x >>= 1;
+    res += 1;
+  }
+  return res;
+}
+
+#endif 
+
+#endif /* BITOPS_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/curve.c b/Build/source/libs/potrace/potrace-src/src/curve.c
new file mode 100644
index 00000000000..d782f22ea65
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/curve.c
@@ -0,0 +1,112 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* private part of the path and curve data structures */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "potracelib.h"
+#include "lists.h"
+#include "curve.h"
+
+#define SAFE_CALLOC(var, n, typ) \
+  if ((var = (typ *)calloc(n, sizeof(typ))) == NULL) goto calloc_error 
+
+/* ---------------------------------------------------------------------- */
+/* allocate and free path objects */
+
+path_t *path_new(void) {
+  path_t *p = NULL;
+  privpath_t *priv = NULL;
+
+  SAFE_CALLOC(p, 1, path_t);
+  memset(p, 0, sizeof(path_t));
+  SAFE_CALLOC(priv, 1, privpath_t);
+  memset(priv, 0, sizeof(privpath_t));
+  p->priv = priv;
+  return p;
+
+ calloc_error:
+  free(p);
+  free(priv);
+  return NULL;
+}
+
+/* free the members of the given curve structure. Leave errno unchanged. */
+static void privcurve_free_members(privcurve_t *curve) {
+  free(curve->tag);
+  free(curve->c);
+  free(curve->vertex);
+  free(curve->alpha);
+  free(curve->alpha0);
+  free(curve->beta);
+}
+
+/* free a path. Leave errno untouched. */
+void path_free(path_t *p) {
+  if (p) {
+    if (p->priv) {
+      free(p->priv->pt);
+      free(p->priv->lon);
+      free(p->priv->sums);
+      free(p->priv->po);
+      privcurve_free_members(&p->priv->curve);
+      privcurve_free_members(&p->priv->ocurve);
+    }
+    free(p->priv);
+    /* do not free p->fcurve ! */
+  }
+  free(p);
+}  
+
+/* free a pathlist, leaving errno untouched. */
+void pathlist_free(path_t *plist) {
+  path_t *p;
+
+  list_forall_unlink(p, plist) {
+    path_free(p);
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* initialize and finalize curve structures */
+
+typedef dpoint_t dpoint3_t[3];
+
+/* initialize the members of the given curve structure to size m.
+   Return 0 on success, 1 on error with errno set. */
+int privcurve_init(privcurve_t *curve, int n) {
+  memset(curve, 0, sizeof(privcurve_t));
+  curve->n = n;
+  SAFE_CALLOC(curve->tag, n, int);
+  SAFE_CALLOC(curve->c, n, dpoint3_t);
+  SAFE_CALLOC(curve->vertex, n, dpoint_t);
+  SAFE_CALLOC(curve->alpha, n, double);
+  SAFE_CALLOC(curve->alpha0, n, double);
+  SAFE_CALLOC(curve->beta, n, double);
+  return 0;
+
+ calloc_error:
+  free(curve->tag);
+  free(curve->c);
+  free(curve->vertex);
+  free(curve->alpha);
+  free(curve->alpha0);
+  free(curve->beta);
+  return 1;
+}
+
+/* copy private to public curve structure */
+void privcurve_to_curve(privcurve_t *pc, potrace_curve_t *c) {
+  c->n = pc->n;
+  c->tag = pc->tag;
+  c->c = pc->c;
+}
+    
diff --git a/Build/source/libs/potrace/potrace-src/src/curve.h b/Build/source/libs/potrace/potrace-src/src/curve.h
new file mode 100644
index 00000000000..feb95b39b49
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/curve.h
@@ -0,0 +1,77 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifndef CURVE_H
+#define CURVE_H
+
+#include "auxiliary.h"
+
+/* vertex is c[1] for tag=POTRACE_CORNER, and the intersection of
+   .c[-1][2]..c[0] and c[1]..c[2] for tag=POTRACE_CURVETO. alpha is only
+   defined for tag=POTRACE_CURVETO and is the alpha parameter of the curve:
+   .c[-1][2]..c[0] = alpha*(.c[-1][2]..vertex), and
+   c[2]..c[1] = alpha*(c[2]..vertex).
+   Beta is so that (.beta[i])[.vertex[i],.vertex[i+1]] = .c[i][2].
+*/
+
+struct privcurve_s {
+  int n;            /* number of segments */
+  int *tag;         /* tag[n]: POTRACE_CORNER or POTRACE_CURVETO */
+  dpoint_t (*c)[3]; /* c[n][i]: control points. 
+		       c[n][0] is unused for tag[n]=POTRACE_CORNER */
+  /* the remainder of this structure is special to privcurve, and is
+     used in EPS debug output and special EPS "short coding". These
+     fields are valid only if "alphacurve" is set. */
+  int alphacurve;   /* have the following fields been initialized? */
+  dpoint_t *vertex; /* for POTRACE_CORNER, this equals c[1] */
+  double *alpha;    /* only for POTRACE_CURVETO */
+  double *alpha0;   /* "uncropped" alpha parameter - for debug output only */
+  double *beta;
+};
+typedef struct privcurve_s privcurve_t;
+
+struct sums_s {
+  double x;
+  double y;
+  double x2;
+  double xy;
+  double y2;
+};
+typedef struct sums_s sums_t;
+
+/* the path structure is filled in with information about a given path
+   as it is accumulated and passed through the different stages of the
+   Potrace algorithm. Backends only need to read the fcurve and fm
+   fields of this data structure, but debugging backends may read
+   other fields. */
+struct potrace_privpath_s {
+  int len;
+  point_t *pt;     /* pt[len]: path as extracted from bitmap */
+  int *lon;        /* lon[len]: (i,lon[i]) = longest straight line from i */
+
+  int x0, y0;      /* origin for sums */
+  sums_t *sums;    /* sums[len+1]: cache for fast summing */
+
+  int m;           /* length of optimal polygon */
+  int *po;         /* po[m]: optimal polygon */
+
+  privcurve_t curve;   /* curve[m]: array of curve elements */
+  privcurve_t ocurve;  /* ocurve[om]: array of curve elements */
+  privcurve_t *fcurve;  /* final curve: this points to either curve or
+		       ocurve. Do not free this separately. */
+};
+typedef struct potrace_privpath_s potrace_privpath_t;
+
+/* shorter names */
+typedef potrace_privpath_t privpath_t;
+typedef potrace_path_t path_t;
+
+path_t *path_new(void);
+void path_free(path_t *p);
+void pathlist_free(path_t *plist);
+int privcurve_init(privcurve_t *curve, int n);
+void privcurve_to_curve(privcurve_t *pc, potrace_curve_t *c);
+
+#endif /* CURVE_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/decompose.c b/Build/source/libs/potrace/potrace-src/src/decompose.c
new file mode 100644
index 00000000000..26126377ad8
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/decompose.c
@@ -0,0 +1,517 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "lists.h"
+#include "bitmap.h"
+#include "decompose.h"
+#include "progress.h"
+
+/* ---------------------------------------------------------------------- */
+/* deterministically and efficiently hash (x,y) into a pseudo-random bit */
+
+static inline int detrand(int x, int y) {
+  unsigned int z;
+  static const unsigned char t[256] = { 
+    /* non-linear sequence: constant term of inverse in GF(8), 
+       mod x^8+x^4+x^3+x+1 */
+    0, 1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 
+    0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 
+    0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 
+    1, 0, 1, 1, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 
+    0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 0, 
+    0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 
+    0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 1, 0, 
+    0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 
+    1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 0, 
+    0, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 
+    1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 
+  };
+
+  /* 0x04b3e375 and 0x05a8ef93 are chosen to contain every possible
+     5-bit sequence */
+  z = ((0x04b3e375 * x) ^ y) * 0x05a8ef93;
+  z = t[z & 0xff] ^ t[(z>>8) & 0xff] ^ t[(z>>16) & 0xff] ^ t[(z>>24) & 0xff];
+  return z;
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary bitmap manipulations */
+
+/* set the excess padding to 0 */
+static void bm_clearexcess(potrace_bitmap_t *bm) {
+  potrace_word mask;
+  int y;
+
+  if (bm->w % BM_WORDBITS != 0) {
+    mask = BM_ALLBITS << (BM_WORDBITS - (bm->w % BM_WORDBITS));
+    for (y=0; y<bm->h; y++) {
+      *bm_index(bm, bm->w, y) &= mask;
+    }
+  }
+}
+
+struct bbox_s {
+  int x0, x1, y0, y1;    /* bounding box */
+};
+typedef struct bbox_s bbox_t;
+
+/* clear the bm, assuming the bounding box is set correctly (faster
+   than clearing the whole bitmap) */
+static void clear_bm_with_bbox(potrace_bitmap_t *bm, bbox_t *bbox) {
+  int imin = (bbox->x0 / BM_WORDBITS);
+  int imax = ((bbox->x1 + BM_WORDBITS-1) / BM_WORDBITS);
+  int i, y;
+
+  for (y=bbox->y0; y<bbox->y1; y++) {
+    for (i=imin; i<imax; i++) {
+      bm_scanline(bm, y)[i] = 0;
+    }
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions */
+
+/* return the "majority" value of bitmap bm at intersection (x,y). We
+   assume that the bitmap is balanced at "radius" 1.  */
+static int majority(potrace_bitmap_t *bm, int x, int y) {
+  int i, a, ct;
+
+  for (i=2; i<5; i++) { /* check at "radius" i */
+    ct = 0;
+    for (a=-i+1; a<=i-1; a++) {
+      ct += BM_GET(bm, x+a, y+i-1) ? 1 : -1;
+      ct += BM_GET(bm, x+i-1, y+a-1) ? 1 : -1;
+      ct += BM_GET(bm, x+a-1, y-i) ? 1 : -1;
+      ct += BM_GET(bm, x-i, y+a) ? 1 : -1;
+    }
+    if (ct>0) {
+      return 1;
+    } else if (ct<0) {
+      return 0;
+    }
+  }
+  return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* decompose image into paths */
+
+/* efficiently invert bits [x,infty) and [xa,infty) in line y. Here xa
+   must be a multiple of BM_WORDBITS. */
+static void xor_to_ref(potrace_bitmap_t *bm, int x, int y, int xa) {
+  int xhi = x & -BM_WORDBITS;
+  int xlo = x & (BM_WORDBITS-1);  /* = x % BM_WORDBITS */
+  int i;
+  
+  if (xhi<xa) {
+    for (i = xhi; i < xa; i+=BM_WORDBITS) {
+      *bm_index(bm, i, y) ^= BM_ALLBITS;
+    }
+  } else {
+    for (i = xa; i < xhi; i+=BM_WORDBITS) {
+      *bm_index(bm, i, y) ^= BM_ALLBITS;
+    }
+  }
+  /* note: the following "if" is needed because x86 treats a<<b as
+     a<<(b&31). I spent hours looking for this bug. */
+  if (xlo) {
+    *bm_index(bm, xhi, y) ^= (BM_ALLBITS << (BM_WORDBITS - xlo));
+  }
+}
+
+/* a path is represented as an array of points, which are thought to
+   lie on the corners of pixels (not on their centers). The path point
+   (x,y) is the lower left corner of the pixel (x,y). Paths are
+   represented by the len/pt components of a path_t object (which
+   also stores other information about the path) */
+
+/* xor the given pixmap with the interior of the given path. Note: the
+   path must be within the dimensions of the pixmap. */
+static void xor_path(potrace_bitmap_t *bm, path_t *p) {
+  int xa, x, y, k, y1;
+
+  if (p->priv->len <= 0) {  /* a path of length 0 is silly, but legal */
+    return;
+  }
+
+  y1 = p->priv->pt[p->priv->len-1].y;
+
+  xa = p->priv->pt[0].x & -BM_WORDBITS;
+  for (k=0; k<p->priv->len; k++) {
+    x = p->priv->pt[k].x;
+    y = p->priv->pt[k].y;
+
+    if (y != y1) {
+      /* efficiently invert the rectangle [x,xa] x [y,y1] */
+      xor_to_ref(bm, x, min(y,y1), xa);
+      y1 = y;
+    }
+  }
+}
+
+/* Find the bounding box of a given path. Path is assumed to be of
+   non-zero length. */
+static void setbbox_path(bbox_t *bbox, path_t *p) {
+  int x, y;
+  int k;
+
+  bbox->y0 = INT_MAX;
+  bbox->y1 = 0;
+  bbox->x0 = INT_MAX;
+  bbox->x1 = 0;
+
+  for (k=0; k<p->priv->len; k++) {
+    x = p->priv->pt[k].x;
+    y = p->priv->pt[k].y;
+
+    if (x < bbox->x0) {
+      bbox->x0 = x;
+    }
+    if (x > bbox->x1) {
+      bbox->x1 = x;
+    }
+    if (y < bbox->y0) {
+      bbox->y0 = y;
+    }
+    if (y > bbox->y1) {
+      bbox->y1 = y;
+    }
+  }
+}
+
+/* compute a path in the given pixmap, separating black from white.
+   Start path at the point (x0,x1), which must be an upper left corner
+   of the path. Also compute the area enclosed by the path. Return a
+   new path_t object, or NULL on error (note that a legitimate path
+   cannot have length 0). Sign is required for correct interpretation
+   of turnpolicies. */
+static path_t *findpath(potrace_bitmap_t *bm, int x0, int y0, int sign, int turnpolicy) {
+  int x, y, dirx, diry, len, size, area;
+  int c, d, tmp;
+  point_t *pt, *pt1;
+  path_t *p = NULL;
+
+  x = x0;
+  y = y0;
+  dirx = 0;
+  diry = -1;
+
+  len = size = 0;
+  pt = NULL;
+  area = 0;
+  
+  while (1) {
+    /* add point to path */
+    if (len>=size) {
+      size += 100;
+      size = (int)(1.3 * size);
+      pt1 = (point_t *)realloc(pt, size * sizeof(point_t));
+      if (!pt1) {
+	goto error;
+      }
+      pt = pt1;
+    }
+    pt[len].x = x;
+    pt[len].y = y;
+    len++;
+    
+    /* move to next point */
+    x += dirx;
+    y += diry;
+    area += x*diry;
+    
+    /* path complete? */
+    if (x==x0 && y==y0) {
+      break;
+    }
+    
+    /* determine next direction */
+    c = BM_GET(bm, x + (dirx+diry-1)/2, y + (diry-dirx-1)/2);
+    d = BM_GET(bm, x + (dirx-diry-1)/2, y + (diry+dirx-1)/2);
+    
+    if (c && !d) {               /* ambiguous turn */
+      if (turnpolicy == POTRACE_TURNPOLICY_RIGHT
+	  || (turnpolicy == POTRACE_TURNPOLICY_BLACK && sign == '+')
+	  || (turnpolicy == POTRACE_TURNPOLICY_WHITE && sign == '-')
+	  || (turnpolicy == POTRACE_TURNPOLICY_RANDOM && detrand(x,y))
+	  || (turnpolicy == POTRACE_TURNPOLICY_MAJORITY && majority(bm, x, y))
+	  || (turnpolicy == POTRACE_TURNPOLICY_MINORITY && !majority(bm, x, y))) {
+	tmp = dirx;              /* right turn */
+	dirx = diry;
+	diry = -tmp;
+      } else {
+	tmp = dirx;              /* left turn */
+	dirx = -diry;
+	diry = tmp;
+      }
+    } else if (c) {              /* right turn */
+      tmp = dirx;
+      dirx = diry;
+      diry = -tmp;
+    } else if (!d) {             /* left turn */
+      tmp = dirx;
+      dirx = -diry;
+      diry = tmp;
+    }
+  } /* while this path */
+
+  /* allocate new path object */
+  p = path_new();
+  if (!p) {
+    goto error;
+  }
+
+  p->priv->pt = pt;
+  p->priv->len = len;
+  p->area = area;
+  p->sign = sign;
+
+  return p;
+ 
+ error:
+   free(pt);
+   return NULL; 
+}
+
+/* Give a tree structure to the given path list, based on "insideness"
+   testing. I.e., path A is considered "below" path B if it is inside
+   path B. The input pathlist is assumed to be ordered so that "outer"
+   paths occur before "inner" paths. The tree structure is stored in
+   the "childlist" and "sibling" components of the path_t
+   structure. The linked list structure is also changed so that
+   negative path components are listed immediately after their
+   positive parent.  Note: some backends may ignore the tree
+   structure, others may use it e.g. to group path components. We
+   assume that in the input, point 0 of each path is an "upper left"
+   corner of the path, as returned by bm_to_pathlist. This makes it
+   easy to find an "interior" point. The bm argument should be a
+   bitmap of the correct size (large enough to hold all the paths),
+   and will be used as scratch space. Return 0 on success or -1 on
+   error with errno set. */
+
+static void pathlist_to_tree(path_t *plist, potrace_bitmap_t *bm) {
+  path_t *p, *p1;
+  path_t *heap, *heap1;
+  path_t *cur;
+  path_t *head;
+  path_t **plist_hook;          /* for fast appending to linked list */
+  path_t **hook_in, **hook_out; /* for fast appending to linked list */
+  bbox_t bbox;
+  
+  bm_clear(bm, 0);
+
+  /* save original "next" pointers */
+  list_forall(p, plist) {
+    p->sibling = p->next;
+    p->childlist = NULL;
+  }
+  
+  heap = plist;
+
+  /* the heap holds a list of lists of paths. Use "childlist" field
+     for outer list, "next" field for inner list. Each of the sublists
+     is to be turned into a tree. This code is messy, but it is
+     actually fast. Each path is rendered exactly once. We use the
+     heap to get a tail recursive algorithm: the heap holds a list of
+     pathlists which still need to be transformed. */
+
+  while (heap) {
+    /* unlink first sublist */
+    cur = heap;
+    heap = heap->childlist;
+    cur->childlist = NULL;
+  
+    /* unlink first path */
+    head = cur;
+    cur = cur->next;
+    head->next = NULL;
+
+    /* render path */
+    xor_path(bm, head);
+    setbbox_path(&bbox, head);
+
+    /* now do insideness test for each element of cur; append it to
+       head->childlist if it's inside head, else append it to
+       head->next. */
+    hook_in=&head->childlist;
+    hook_out=&head->next;
+    list_forall_unlink(p, cur) {
+      if (p->priv->pt[0].y <= bbox.y0) {
+	list_insert_beforehook(p, hook_out);
+	/* append the remainder of the list to hook_out */
+	*hook_out = cur;
+	break;
+      }
+      if (BM_GET(bm, p->priv->pt[0].x, p->priv->pt[0].y-1)) {
+	list_insert_beforehook(p, hook_in);
+      } else {
+	list_insert_beforehook(p, hook_out);
+      }
+    }
+
+    /* clear bm */
+    clear_bm_with_bbox(bm, &bbox);
+
+    /* now schedule head->childlist and head->next for further
+       processing */
+    if (head->next) {
+      head->next->childlist = heap;
+      heap = head->next;
+    }
+    if (head->childlist) {
+      head->childlist->childlist = heap;
+      heap = head->childlist;
+    }
+  }
+  
+  /* copy sibling structure from "next" to "sibling" component */
+  p = plist;
+  while (p) {
+    p1 = p->sibling;
+    p->sibling = p->next;
+    p = p1;
+  }
+
+  /* reconstruct a new linked list ("next") structure from tree
+     ("childlist", "sibling") structure. This code is slightly messy,
+     because we use a heap to make it tail recursive: the heap
+     contains a list of childlists which still need to be
+     processed. */
+  heap = plist;
+  if (heap) {
+    heap->next = NULL;  /* heap is a linked list of childlists */
+  }
+  plist = NULL;
+  plist_hook = &plist;
+  while (heap) {
+    heap1 = heap->next;
+    for (p=heap; p; p=p->sibling) {
+      /* p is a positive path */
+      /* append to linked list */
+      list_insert_beforehook(p, plist_hook);
+      
+      /* go through its children */
+      for (p1=p->childlist; p1; p1=p1->sibling) {
+	/* append to linked list */
+	list_insert_beforehook(p1, plist_hook);
+	/* append its childlist to heap, if non-empty */
+	if (p1->childlist) {
+	  list_append(path_t, heap1, p1->childlist);
+	}
+      }
+    }
+    heap = heap1;
+  }
+
+  return;
+}
+
+/* find the next set pixel in a row <= y. Pixels are searched first
+   left-to-right, then top-down. In other words, (x,y)<(x',y') if y>y'
+   or y=y' and x<x'. If found, return 0 and store pixel in
+   (*xp,*yp). Else return 1. Note that this function assumes that
+   excess bytes have been cleared with bm_clearexcess. */
+static int findnext(potrace_bitmap_t *bm, int *xp, int *yp) {
+  int x;
+  int y;
+  int x0;
+
+  x0 = (*xp) & ~(BM_WORDBITS-1);
+
+  for (y=*yp; y>=0; y--) {
+    for (x=x0; x<bm->w; x+=BM_WORDBITS) {
+      if (*bm_index(bm, x, y)) {
+	while (!BM_GET(bm, x, y)) {
+	  x++;
+	}
+	/* found */
+	*xp = x;
+	*yp = y;
+	return 0;
+      }
+    }
+    x0 = 0;
+  }
+  /* not found */
+  return 1;
+}
+
+/* Decompose the given bitmap into paths. Returns a linked list of
+   path_t objects with the fields len, pt, area, sign filled
+   in. Returns 0 on success with plistp set, or -1 on error with errno
+   set. */
+
+int bm_to_pathlist(const potrace_bitmap_t *bm, path_t **plistp, const potrace_param_t *param, progress_t *progress) {
+  int x;
+  int y;
+  path_t *p;
+  path_t *plist = NULL;  /* linked list of path objects */
+  path_t **plist_hook = &plist;  /* used to speed up appending to linked list */
+  potrace_bitmap_t *bm1 = NULL;
+  int sign;
+
+  bm1 = bm_dup(bm);
+  if (!bm1) {
+    goto error;
+  }
+
+  /* be sure the byte padding on the right is set to 0, as the fast
+     pixel search below relies on it */
+  bm_clearexcess(bm1);
+
+  /* iterate through components */
+  x = 0;
+  y = bm1->h - 1;
+  while (findnext(bm1, &x, &y) == 0) { 
+    /* calculate the sign by looking at the original */
+    sign = BM_GET(bm, x, y) ? '+' : '-';
+
+    /* calculate the path */
+    p = findpath(bm1, x, y+1, sign, param->turnpolicy);
+    if (p==NULL) {
+      goto error;
+    }
+
+    /* update buffered image */
+    xor_path(bm1, p);
+
+    /* if it's a turd, eliminate it, else append it to the list */
+    if (p->area <= param->turdsize) {
+      path_free(p);
+    } else {
+      list_insert_beforehook(p, plist_hook);
+    }
+
+    if (bm1->h > 0) { /* to be sure */
+      progress_update(1-y/(double)bm1->h, progress);
+    }
+  }
+
+  pathlist_to_tree(plist, bm1);
+  bm_free(bm1);
+  *plistp = plist;
+
+  progress_update(1.0, progress);
+
+  return 0;
+
+ error:
+  bm_free(bm1);
+  list_forall_unlink(p, plist) {
+    path_free(p);
+  }
+  return -1;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/decompose.h b/Build/source/libs/potrace/potrace-src/src/decompose.h
new file mode 100644
index 00000000000..8ae89b8adc3
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/decompose.h
@@ -0,0 +1,16 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef DECOMPOSE_H
+#define DECOMPOSE_H
+
+#include "potracelib.h"
+#include "progress.h"
+#include "curve.h"
+
+int bm_to_pathlist(const potrace_bitmap_t *bm, path_t **plistp, const potrace_param_t *param, progress_t *progress);
+
+#endif /* DECOMPOSE_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/flate.c b/Build/source/libs/potrace/potrace-src/src/flate.c
new file mode 100644
index 00000000000..9965d15d3f0
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/flate.c
@@ -0,0 +1,380 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* the PostScript compression module of Potrace. The basic interface
+   is through the *_xship function, which processes a byte array and
+   outputs it in compressed or verbatim form, depending on whether
+   filter is 1 or 0. To flush the output, simply call with the empty
+   string and filter=0. filter=2 is used to output encoded text but
+   without the PostScript header to turn on the encoding. Each
+   function has variants for shipping a single character, a
+   null-terminated string, or a byte array. */
+
+/* different compression algorithms are available. There is
+   dummy_xship, which is just the identity, and flate_xship, which
+   uses zlib compression. Also, lzw_xship provides LZW compression
+   from the file lzw.c/h. a85_xship provides a85-encoding without
+   compression. Each function returns the actual number of characters
+   written. */
+
+/* note: the functions provided here have global state and are not
+   reentrant */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <errno.h>
+
+#ifdef HAVE_ZLIB
+#include <zlib.h>
+#endif
+
+#include "flate.h"
+#include "lzw.h"
+
+#define OUTSIZE 1000
+
+static int a85init(FILE *f);
+static int a85finish(FILE *f);
+static int a85write(FILE *f, char *buf, int n);
+static int a85out(FILE *f, int n);
+static int a85spool(FILE *f, char c);
+
+/* ---------------------------------------------------------------------- */
+/* dummy interface: no encoding */
+
+int dummy_xship(FILE *f, int filter, char *s, int len) {
+  fwrite(s, 1, len, f);
+  return len;
+}
+
+/* ---------------------------------------------------------------------- */
+/* flate interface: zlib (=postscript level 3) compression and a85 */
+
+#ifdef HAVE_ZLIB
+
+int pdf_xship(FILE *f, int filter, char *s, int len) {
+	static int fstate = 0;
+	static z_stream c_stream;
+	char outbuf[OUTSIZE];
+	int err;
+	int n=0;
+
+  if (filter && !fstate) {
+    /* switch on filtering */
+    c_stream.zalloc = Z_NULL;
+    c_stream.zfree = Z_NULL;
+    c_stream.opaque = Z_NULL;
+    err = deflateInit(&c_stream, 9);
+    if (err != Z_OK) {
+      fprintf(stderr, "deflateInit: %s (%d)\n", c_stream.msg, err);
+      exit(1);
+    }
+    c_stream.avail_in = 0;
+    fstate = 1;
+  } else if (!filter && fstate) {
+    /* switch off filtering */
+    /* flush stream */
+    do {
+      c_stream.next_out = (Bytef*)outbuf;
+      c_stream.avail_out = OUTSIZE;
+
+      err = deflate(&c_stream, Z_FINISH);
+      if (err != Z_OK && err != Z_STREAM_END) {
+	fprintf(stderr, "deflate: %s (%d)\n", c_stream.msg, err);
+	exit(1);
+      }
+      n += fwrite(outbuf, 1, OUTSIZE-c_stream.avail_out, f);
+    } while (err != Z_STREAM_END);
+
+    fstate = 0;
+  }
+  if (!fstate) {
+    fwrite(s, 1, len, f);
+    return n+len;
+  }
+  
+  /* do the actual compression */
+  c_stream.next_in = (Bytef*) s;
+  c_stream.avail_in = len;
+
+  do {
+    c_stream.next_out = (Bytef*) outbuf;
+    c_stream.avail_out = OUTSIZE;
+
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    if (err != Z_OK) {
+      fprintf(stderr, "deflate: %s (%d)\n", c_stream.msg, err);
+      exit(1);
+    }
+    n += fwrite(outbuf, 1, OUTSIZE-c_stream.avail_out, f);
+  } while (!c_stream.avail_out);
+  
+  return n;
+}
+
+/* ship len bytes from s using zlib compression. */
+int flate_xship(FILE *f, int filter, char *s, int len) {
+  static int fstate = 0;
+  static z_stream c_stream;
+  char outbuf[OUTSIZE];
+  int err;
+  int n=0;
+
+  if (filter && !fstate) {
+    /* switch on filtering */
+    if (filter == 1) {
+      n += fprintf(f, "currentfile /ASCII85Decode filter /FlateDecode filter cvx exec\n");
+    }
+    c_stream.zalloc = Z_NULL;
+    c_stream.zfree = Z_NULL;
+    c_stream.opaque = Z_NULL;
+    err = deflateInit(&c_stream, 9);
+    if (err != Z_OK) {
+      fprintf(stderr, "deflateInit: %s (%d)\n", c_stream.msg, err);
+      exit(1);
+    }
+    c_stream.avail_in = 0;
+    n += a85init(f);
+    fstate = 1;
+  } else if (!filter && fstate) {
+    /* switch off filtering */
+    /* flush stream */
+    do {
+      c_stream.next_out = (Bytef*)outbuf;
+      c_stream.avail_out = OUTSIZE;
+
+      err = deflate(&c_stream, Z_FINISH);
+      if (err != Z_OK && err != Z_STREAM_END) {
+	fprintf(stderr, "deflate: %s (%d)\n", c_stream.msg, err);
+	exit(1);
+      }
+      n += a85write(f, outbuf, OUTSIZE-c_stream.avail_out);
+    } while (err != Z_STREAM_END);
+
+    n += a85finish(f);
+
+    fstate = 0;
+  }
+  if (!fstate) {
+    fwrite(s, 1, len, f);
+    return n+len;
+  }
+  
+  /* do the actual compression */
+  c_stream.next_in = (Bytef*) s;
+  c_stream.avail_in = len;
+
+  do {
+    c_stream.next_out = (Bytef*) outbuf;
+    c_stream.avail_out = OUTSIZE;
+
+    err = deflate(&c_stream, Z_NO_FLUSH);
+    if (err != Z_OK) {
+      fprintf(stderr, "deflate: %s (%d)\n", c_stream.msg, err);
+      exit(1);
+    }
+    n += a85write(f, outbuf, OUTSIZE-c_stream.avail_out);
+  } while (!c_stream.avail_out);
+  
+  return n;
+}
+
+#else  /* HAVE_ZLIB */
+
+int pdf_xship(FILE *f, int filter, char *s, int len) {
+  return dummy_xship(f, filter, s, len);
+}
+
+int flate_xship(FILE *f, int filter, char *s, int len) {
+  return dummy_xship(f, filter, s, len);
+}
+
+#endif /* HAVE_ZLIB */
+
+/* ---------------------------------------------------------------------- */
+/* lzw interface: LZW (=postscript level 2) compression with a85.
+   This relies on lzw.c/h to do the actual compression. */
+
+/* use Postscript level 2 compression. Ship len bytes from str. */
+int lzw_xship(FILE *f, int filter, char *str, int len) {
+  static int fstate = 0;
+  static lzw_stream_t *s = NULL;
+  char outbuf[OUTSIZE];
+  int err;
+  int n=0;
+
+  if (filter && !fstate) {
+    /* switch on filtering */
+    if (filter == 1) {
+      n += fprintf(f, "currentfile /ASCII85Decode filter /LZWDecode filter cvx exec\n");
+    }
+    s = lzw_init();
+    if (s == NULL) {
+      fprintf(stderr, "lzw_init: %s\n", strerror(errno));
+      exit(1);
+    }
+    n += a85init(f);
+    fstate = 1;
+  } else if (!filter && fstate) {
+    /* switch off filtering */
+    /* flush stream */
+    s->next_in = 0;
+    s->avail_in = 0;
+    do {
+      s->next_out = outbuf;
+      s->avail_out = OUTSIZE;
+
+      err = lzw_compress(s, LZW_EOD);
+      if (err) {
+	fprintf(stderr, "lzw_compress: %s\n", strerror(errno));
+	exit(1);
+      }
+      n += a85write(f, outbuf, OUTSIZE - s->avail_out);
+    } while (s->avail_out == 0);
+
+    n += a85finish(f);
+
+    lzw_free(s);
+    s = NULL;
+
+    fstate = 0;
+  }
+  if (!fstate) {
+    fwrite(str, 1, len, f);
+    return n+len;
+  }
+  
+  /* do the actual compression */
+  s->next_in = str;
+  s->avail_in = len;
+
+  do {
+    s->next_out = outbuf;
+    s->avail_out = OUTSIZE;
+
+    err = lzw_compress(s, LZW_NORMAL);
+    if (err) {
+      fprintf(stderr, "lzw_compress: %s\n", strerror(errno));
+      exit(1);
+    }
+    n += a85write(f, outbuf, OUTSIZE - s->avail_out);
+  } while (s->avail_out == 0);
+  
+  return n;
+}
+
+/* ---------------------------------------------------------------------- */
+/* a85 interface: a85 encoding without compression */
+
+/* ship len bytes from s using a85 encoding only. */
+int a85_xship(FILE *f, int filter, char *s, int len) {
+  static int fstate = 0;
+  int n=0;
+
+  if (filter && !fstate) {
+    /* switch on filtering */
+    if (filter == 1) {
+      n += fprintf(f, "currentfile /ASCII85Decode filter cvx exec\n");
+    }
+    n += a85init(f);
+    fstate = 1;
+  } else if (!filter && fstate) {
+    /* switch off filtering */
+    /* flush stream */
+    n += a85finish(f);
+    fstate = 0;
+  }
+  if (!fstate) {
+    fwrite(s, 1, len, f);
+    return n+len;
+  }
+  
+  n += a85write(f, s, len);
+  
+  return n;
+}
+
+/* ---------------------------------------------------------------------- */
+/* low-level a85 backend */
+
+static unsigned long a85buf[4];
+static int a85n;
+static int a85col;
+
+static int a85init(FILE *f) {
+  a85n = 0;
+  a85col = 0;
+  return 0;
+}
+
+static int a85finish(FILE *f) {
+  int r=0;
+
+  if (a85n) {
+    r+=a85out(f, a85n);
+  }
+  fputs("~>\n", f);
+  return r+2;
+}
+
+static int a85write(FILE *f, char *buf, int n) {
+  int i;
+  int r=0;
+
+  for (i=0; i<n; i++) {
+    a85buf[a85n] = (unsigned char)buf[i];
+    a85n++;
+    
+    if (a85n == 4) {
+      r+=a85out(f, 4);
+      a85n = 0;
+    }
+  }
+  return r;
+}
+
+static int a85out(FILE *f, int n) {
+  char out[5];
+  unsigned long s;
+  int r=0;
+  int i;
+
+  for (i=n; i<4; i++) {
+    a85buf[i] = 0;
+  }
+
+  s = (a85buf[0]<<24) + (a85buf[1]<<16) + (a85buf[2]<<8) + (a85buf[3]<<0);
+
+  if (!s) {
+    r+=a85spool(f, 'z');
+  } else {
+    for (i=4; i>=0; i--) {
+      out[i] = s % 85;
+      s /= 85;
+    }
+    for (i=0; i<n+1; i++) {
+      r+=a85spool(f, out[i]+33);
+    }
+  } 
+  return r;
+}
+
+static int a85spool(FILE *f, char c) {
+  fputc(c, f);
+
+  a85col++;
+  if (a85col>70) {
+    fputc('\n', f);
+    a85col=0;
+    return 2;
+  }
+  
+  return 1;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/flate.h b/Build/source/libs/potrace/potrace-src/src/flate.h
new file mode 100644
index 00000000000..7b51245503d
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/flate.h
@@ -0,0 +1,15 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef FLATE_H
+#define FLATE_H
+
+int dummy_xship(FILE *f, int filter, char *s, int len);
+int flate_xship(FILE *f, int filter, char *s, int len);
+int pdf_xship(FILE *f, int filter, char *s, int len);
+int lzw_xship(FILE *f, int filter, char *s, int len);
+int a85_xship(FILE *f, int filter, char *s, int len);
+
+#endif /* FLATE_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/getopt.c b/Build/source/libs/potrace/potrace-src/src/getopt.c
new file mode 100644
index 00000000000..0c8fdd11bb3
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/getopt.c
@@ -0,0 +1,1061 @@
+/* Getopt for GNU.
+   NOTE: getopt is now part of the C library, so if you don't know what
+   "Keep this file name-space clean" means, talk to drepper@gnu.org
+   before changing it!
+
+   Copyright (C) 1987, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 2000
+   	Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.  */
+
+/* This tells Alpha OSF/1 not to define a getopt prototype in <stdio.h>.
+   Ditto for AIX 3.2 and <stdlib.h>.  */
+#ifndef _NO_PROTO
+# define _NO_PROTO
+#endif
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#if !defined __STDC__ || !__STDC__
+/* This is a separate conditional since some stdc systems
+   reject `defined (const)'.  */
+# ifndef const
+#  define const
+# endif
+#endif
+
+#include <stdio.h>
+
+/* Comment out all this code if we are using the GNU C Library, and are not
+   actually compiling the library itself.  This code is part of the GNU C
+   Library, but also included in many other GNU distributions.  Compiling
+   and linking in this code is a waste when using the GNU C library
+   (especially if it is a shared library).  Rather than having every GNU
+   program understand `configure --with-gnu-libc' and omit the object files,
+   it is simpler to just do this in the source for each such file.  */
+
+#define GETOPT_INTERFACE_VERSION 2
+#if !defined _LIBC && defined __GLIBC__ && __GLIBC__ >= 2
+# include <gnu-versions.h>
+# if _GNU_GETOPT_INTERFACE_VERSION == GETOPT_INTERFACE_VERSION
+#  define ELIDE_CODE
+# endif
+#endif
+
+#ifndef ELIDE_CODE
+
+
+/* This needs to come after some library #include
+   to get __GNU_LIBRARY__ defined.  */
+#ifdef	__GNU_LIBRARY__
+/* Don't include stdlib.h for non-GNU C libraries because some of them
+   contain conflicting prototypes for getopt.  */
+# include <stdlib.h>
+# include <unistd.h>
+#endif	/* GNU C library.  */
+
+#ifdef VMS
+# include <unixlib.h>
+# if HAVE_STRING_H - 0
+#  include <string.h>
+# endif
+#endif
+
+#ifndef _
+/* This is for other GNU distributions with internationalized messages.  */
+# if defined HAVE_LIBINTL_H || defined _LIBC
+#  include <libintl.h>
+#  ifndef _
+#   define _(msgid)	gettext (msgid)
+#  endif
+# else
+#  define _(msgid)	(msgid)
+# endif
+#endif
+
+/* This version of `getopt' appears to the caller like standard Unix `getopt'
+   but it behaves differently for the user, since it allows the user
+   to intersperse the options with the other arguments.
+
+   As `getopt' works, it permutes the elements of ARGV so that,
+   when it is done, all the options precede everything else.  Thus
+   all application programs are extended to handle flexible argument order.
+
+   Setting the environment variable POSIXLY_CORRECT disables permutation.
+   Then the behavior is completely standard.
+
+   GNU application programs can use a third alternative mode in which
+   they can distinguish the relative order of options and other arguments.  */
+
+#include "getopt.h"
+
+/* For communication from `getopt' to the caller.
+   When `getopt' finds an option that takes an argument,
+   the argument value is returned here.
+   Also, when `ordering' is RETURN_IN_ORDER,
+   each non-option ARGV-element is returned here.  */
+
+char *optarg;
+
+/* Index in ARGV of the next element to be scanned.
+   This is used for communication to and from the caller
+   and for communication between successive calls to `getopt'.
+
+   On entry to `getopt', zero means this is the first call; initialize.
+
+   When `getopt' returns -1, this is the index of the first of the
+   non-option elements that the caller should itself scan.
+
+   Otherwise, `optind' communicates from one call to the next
+   how much of ARGV has been scanned so far.  */
+
+/* 1003.2 says this must be 1 before any call.  */
+int optind = 1;
+
+/* Formerly, initialization of getopt depended on optind==0, which
+   causes problems with re-calling getopt as programs generally don't
+   know that. */
+
+int __getopt_initialized;
+
+/* The next char to be scanned in the option-element
+   in which the last option character we returned was found.
+   This allows us to pick up the scan where we left off.
+
+   If this is zero, or a null string, it means resume the scan
+   by advancing to the next ARGV-element.  */
+
+static char *nextchar;
+
+/* Callers store zero here to inhibit the error message
+   for unrecognized options.  */
+
+int opterr = 1;
+
+/* Set to an option character which was unrecognized.
+   This must be initialized on some systems to avoid linking in the
+   system's own getopt implementation.  */
+
+int optopt = '?';
+
+/* Describe how to deal with options that follow non-option ARGV-elements.
+
+   If the caller did not specify anything,
+   the default is REQUIRE_ORDER if the environment variable
+   POSIXLY_CORRECT is defined, PERMUTE otherwise.
+
+   REQUIRE_ORDER means don't recognize them as options;
+   stop option processing when the first non-option is seen.
+   This is what Unix does.
+   This mode of operation is selected by either setting the environment
+   variable POSIXLY_CORRECT, or using `+' as the first character
+   of the list of option characters.
+
+   PERMUTE is the default.  We permute the contents of ARGV as we scan,
+   so that eventually all the non-options are at the end.  This allows options
+   to be given in any order, even with programs that were not written to
+   expect this.
+
+   RETURN_IN_ORDER is an option available to programs that were written
+   to expect options and other ARGV-elements in any order and that care about
+   the ordering of the two.  We describe each non-option ARGV-element
+   as if it were the argument of an option with character code 1.
+   Using `-' as the first character of the list of option characters
+   selects this mode of operation.
+
+   The special argument `--' forces an end of option-scanning regardless
+   of the value of `ordering'.  In the case of RETURN_IN_ORDER, only
+   `--' can cause `getopt' to return -1 with `optind' != ARGC.  */
+
+static enum
+{
+  REQUIRE_ORDER, PERMUTE, RETURN_IN_ORDER
+} ordering;
+
+/* Value of POSIXLY_CORRECT environment variable.  */
+static char *posixly_correct;
+
+#ifdef	__GNU_LIBRARY__
+/* We want to avoid inclusion of string.h with non-GNU libraries
+   because there are many ways it can cause trouble.
+   On some systems, it contains special magic macros that don't work
+   in GCC.  */
+# include <string.h>
+# define my_index	strchr
+#else
+
+# if HAVE_STRING_H
+#  include <string.h>
+# else
+#  include <strings.h>
+# endif
+
+/* Avoid depending on library functions or files
+   whose names are inconsistent.  */
+
+#ifndef getenv
+extern char *getenv ();
+#endif
+
+static char *
+my_index (str, chr)
+     const char *str;
+     int chr;
+{
+  while (*str)
+    {
+      if (*str == chr)
+	return (char *) str;
+      str++;
+    }
+  return 0;
+}
+
+/* If using GCC, we can safely declare strlen this way.
+   If not using GCC, it is ok not to declare it.  */
+#ifdef __GNUC__
+/* Note that Motorola Delta 68k R3V7 comes with GCC but not stddef.h.
+   That was relevant to code that was here before.  */
+# if (!defined __STDC__ || !__STDC__) && !defined strlen
+/* gcc with -traditional declares the built-in strlen to return int,
+   and has done so at least since version 2.4.5. -- rms.  */
+extern int strlen (const char *);
+# endif /* not __STDC__ */
+#endif /* __GNUC__ */
+
+#endif /* not __GNU_LIBRARY__ */
+
+/* Handle permutation of arguments.  */
+
+/* Describe the part of ARGV that contains non-options that have
+   been skipped.  `first_nonopt' is the index in ARGV of the first of them;
+   `last_nonopt' is the index after the last of them.  */
+
+static int first_nonopt;
+static int last_nonopt;
+
+#ifdef _LIBC
+/* Bash 2.0 gives us an environment variable containing flags
+   indicating ARGV elements that should not be considered arguments.  */
+
+/* Defined in getopt_init.c  */
+extern char *__getopt_nonoption_flags;
+
+static int nonoption_flags_max_len;
+static int nonoption_flags_len;
+
+static int original_argc;
+static char *const *original_argv;
+
+/* Make sure the environment variable bash 2.0 puts in the environment
+   is valid for the getopt call we must make sure that the ARGV passed
+   to getopt is that one passed to the process.  */
+static void
+__attribute__ ((unused))
+store_args_and_env (int argc, char *const *argv)
+{
+  /* XXX This is no good solution.  We should rather copy the args so
+     that we can compare them later.  But we must not use malloc(3).  */
+  original_argc = argc;
+  original_argv = argv;
+}
+# ifdef text_set_element
+text_set_element (__libc_subinit, store_args_and_env);
+# endif /* text_set_element */
+
+# define SWAP_FLAGS(ch1, ch2) \
+  if (nonoption_flags_len > 0)						      \
+    {									      \
+      char __tmp = __getopt_nonoption_flags[ch1];			      \
+      __getopt_nonoption_flags[ch1] = __getopt_nonoption_flags[ch2];	      \
+      __getopt_nonoption_flags[ch2] = __tmp;				      \
+    }
+#else	/* !_LIBC */
+# define SWAP_FLAGS(ch1, ch2)
+#endif	/* _LIBC */
+
+/* Exchange two adjacent subsequences of ARGV.
+   One subsequence is elements [first_nonopt,last_nonopt)
+   which contains all the non-options that have been skipped so far.
+   The other is elements [last_nonopt,optind), which contains all
+   the options processed since those non-options were skipped.
+
+   `first_nonopt' and `last_nonopt' are relocated so that they describe
+   the new indices of the non-options in ARGV after they are moved.  */
+
+#if defined __STDC__ && __STDC__
+static void exchange (char **);
+#endif
+
+static void
+exchange (argv)
+     char **argv;
+{
+  int bottom = first_nonopt;
+  int middle = last_nonopt;
+  int top = optind;
+  char *tem;
+
+  /* Exchange the shorter segment with the far end of the longer segment.
+     That puts the shorter segment into the right place.
+     It leaves the longer segment in the right place overall,
+     but it consists of two parts that need to be swapped next.  */
+
+#ifdef _LIBC
+  /* First make sure the handling of the `__getopt_nonoption_flags'
+     string can work normally.  Our top argument must be in the range
+     of the string.  */
+  if (nonoption_flags_len > 0 && top >= nonoption_flags_max_len)
+    {
+      /* We must extend the array.  The user plays games with us and
+	 presents new arguments.  */
+      char *new_str = malloc (top + 1);
+      if (new_str == NULL)
+	nonoption_flags_len = nonoption_flags_max_len = 0;
+      else
+	{
+	  memset (__mempcpy (new_str, __getopt_nonoption_flags,
+			     nonoption_flags_max_len),
+		  '\0', top + 1 - nonoption_flags_max_len);
+	  nonoption_flags_max_len = top + 1;
+	  __getopt_nonoption_flags = new_str;
+	}
+    }
+#endif
+
+  while (top > middle && middle > bottom)
+    {
+      if (top - middle > middle - bottom)
+	{
+	  /* Bottom segment is the short one.  */
+	  int len = middle - bottom;
+	  register int i;
+
+	  /* Swap it with the top part of the top segment.  */
+	  for (i = 0; i < len; i++)
+	    {
+	      tem = argv[bottom + i];
+	      argv[bottom + i] = argv[top - (middle - bottom) + i];
+	      argv[top - (middle - bottom) + i] = tem;
+	      SWAP_FLAGS (bottom + i, top - (middle - bottom) + i);
+	    }
+	  /* Exclude the moved bottom segment from further swapping.  */
+	  top -= len;
+	}
+      else
+	{
+	  /* Top segment is the short one.  */
+	  int len = top - middle;
+	  register int i;
+
+	  /* Swap it with the bottom part of the bottom segment.  */
+	  for (i = 0; i < len; i++)
+	    {
+	      tem = argv[bottom + i];
+	      argv[bottom + i] = argv[middle + i];
+	      argv[middle + i] = tem;
+	      SWAP_FLAGS (bottom + i, middle + i);
+	    }
+	  /* Exclude the moved top segment from further swapping.  */
+	  bottom += len;
+	}
+    }
+
+  /* Update records for the slots the non-options now occupy.  */
+
+  first_nonopt += (optind - last_nonopt);
+  last_nonopt = optind;
+}
+
+/* Initialize the internal data when the first call is made.  */
+
+#if defined __STDC__ && __STDC__
+static const char *_getopt_initialize (int, char *const *, const char *);
+#endif
+static const char *
+_getopt_initialize (argc, argv, optstring)
+     int argc;
+     char *const *argv;
+     const char *optstring;
+{
+  /* Start processing options with ARGV-element 1 (since ARGV-element 0
+     is the program name); the sequence of previously skipped
+     non-option ARGV-elements is empty.  */
+
+  first_nonopt = last_nonopt = optind;
+
+  nextchar = NULL;
+
+  posixly_correct = getenv ("POSIXLY_CORRECT");
+
+  /* Determine how to handle the ordering of options and nonoptions.  */
+
+  if (optstring[0] == '-')
+    {
+      ordering = RETURN_IN_ORDER;
+      ++optstring;
+    }
+  else if (optstring[0] == '+')
+    {
+      ordering = REQUIRE_ORDER;
+      ++optstring;
+    }
+  else if (posixly_correct != NULL)
+    ordering = REQUIRE_ORDER;
+  else
+    ordering = PERMUTE;
+
+#ifdef _LIBC
+  if (posixly_correct == NULL
+      && argc == original_argc && argv == original_argv)
+    {
+      if (nonoption_flags_max_len == 0)
+	{
+	  if (__getopt_nonoption_flags == NULL
+	      || __getopt_nonoption_flags[0] == '\0')
+	    nonoption_flags_max_len = -1;
+	  else
+	    {
+	      const char *orig_str = __getopt_nonoption_flags;
+	      int len = nonoption_flags_max_len = strlen (orig_str);
+	      if (nonoption_flags_max_len < argc)
+		nonoption_flags_max_len = argc;
+	      __getopt_nonoption_flags =
+		(char *) malloc (nonoption_flags_max_len);
+	      if (__getopt_nonoption_flags == NULL)
+		nonoption_flags_max_len = -1;
+	      else
+		memset (__mempcpy (__getopt_nonoption_flags, orig_str, len),
+			'\0', nonoption_flags_max_len - len);
+	    }
+	}
+      nonoption_flags_len = nonoption_flags_max_len;
+    }
+  else
+    nonoption_flags_len = 0;
+#endif
+
+  return optstring;
+}
+
+/* Scan elements of ARGV (whose length is ARGC) for option characters
+   given in OPTSTRING.
+
+   If an element of ARGV starts with '-', and is not exactly "-" or "--",
+   then it is an option element.  The characters of this element
+   (aside from the initial '-') are option characters.  If `getopt'
+   is called repeatedly, it returns successively each of the option characters
+   from each of the option elements.
+
+   If `getopt' finds another option character, it returns that character,
+   updating `optind' and `nextchar' so that the next call to `getopt' can
+   resume the scan with the following option character or ARGV-element.
+
+   If there are no more option characters, `getopt' returns -1.
+   Then `optind' is the index in ARGV of the first ARGV-element
+   that is not an option.  (The ARGV-elements have been permuted
+   so that those that are not options now come last.)
+
+   OPTSTRING is a string containing the legitimate option characters.
+   If an option character is seen that is not listed in OPTSTRING,
+   return '?' after printing an error message.  If you set `opterr' to
+   zero, the error message is suppressed but we still return '?'.
+
+   If a char in OPTSTRING is followed by a colon, that means it wants an arg,
+   so the following text in the same ARGV-element, or the text of the following
+   ARGV-element, is returned in `optarg'.  Two colons mean an option that
+   wants an optional arg; if there is text in the current ARGV-element,
+   it is returned in `optarg', otherwise `optarg' is set to zero.
+
+   If OPTSTRING starts with `-' or `+', it requests different methods of
+   handling the non-option ARGV-elements.
+   See the comments about RETURN_IN_ORDER and REQUIRE_ORDER, above.
+
+   Long-named options begin with `--' instead of `-'.
+   Their names may be abbreviated as long as the abbreviation is unique
+   or is an exact match for some defined option.  If they have an
+   argument, it follows the option name in the same ARGV-element, separated
+   from the option name by a `=', or else the in next ARGV-element.
+   When `getopt' finds a long-named option, it returns 0 if that option's
+   `flag' field is nonzero, the value of the option's `val' field
+   if the `flag' field is zero.
+
+   The elements of ARGV aren't really const, because we permute them.
+   But we pretend they're const in the prototype to be compatible
+   with other systems.
+
+   LONGOPTS is a vector of `struct option' terminated by an
+   element containing a name which is zero.
+
+   LONGIND returns the index in LONGOPT of the long-named option found.
+   It is only valid when a long-named option has been found by the most
+   recent call.
+
+   If LONG_ONLY is nonzero, '-' as well as '--' can introduce
+   long-named options.  */
+
+int
+_getopt_internal (argc, argv, optstring, longopts, longind, long_only)
+     int argc;
+     char *const *argv;
+     const char *optstring;
+     const struct option *longopts;
+     int *longind;
+     int long_only;
+{
+  int print_errors = opterr;
+  if (optstring[0] == ':')
+    print_errors = 0;
+
+  if (argc < 1)
+    return -1;
+
+  optarg = NULL;
+
+  if (optind == 0 || !__getopt_initialized)
+    {
+      if (optind == 0)
+	optind = 1;	/* Don't scan ARGV[0], the program name.  */
+      optstring = _getopt_initialize (argc, argv, optstring);
+      __getopt_initialized = 1;
+    }
+
+  /* Test whether ARGV[optind] points to a non-option argument.
+     Either it does not have option syntax, or there is an environment flag
+     from the shell indicating it is not an option.  The later information
+     is only used when the used in the GNU libc.  */
+#ifdef _LIBC
+# define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0'	      \
+		      || (optind < nonoption_flags_len			      \
+			  && __getopt_nonoption_flags[optind] == '1'))
+#else
+# define NONOPTION_P (argv[optind][0] != '-' || argv[optind][1] == '\0')
+#endif
+
+  if (nextchar == NULL || *nextchar == '\0')
+    {
+      /* Advance to the next ARGV-element.  */
+
+      /* Give FIRST_NONOPT & LAST_NONOPT rational values if OPTIND has been
+	 moved back by the user (who may also have changed the arguments).  */
+      if (last_nonopt > optind)
+	last_nonopt = optind;
+      if (first_nonopt > optind)
+	first_nonopt = optind;
+
+      if (ordering == PERMUTE)
+	{
+	  /* If we have just processed some options following some non-options,
+	     exchange them so that the options come first.  */
+
+	  if (first_nonopt != last_nonopt && last_nonopt != optind)
+	    exchange ((char **) argv);
+	  else if (last_nonopt != optind)
+	    first_nonopt = optind;
+
+	  /* Skip any additional non-options
+	     and extend the range of non-options previously skipped.  */
+
+	  while (optind < argc && NONOPTION_P)
+	    optind++;
+	  last_nonopt = optind;
+	}
+
+      /* The special ARGV-element `--' means premature end of options.
+	 Skip it like a null option,
+	 then exchange with previous non-options as if it were an option,
+	 then skip everything else like a non-option.  */
+
+      if (optind != argc && !strcmp (argv[optind], "--"))
+	{
+	  optind++;
+
+	  if (first_nonopt != last_nonopt && last_nonopt != optind)
+	    exchange ((char **) argv);
+	  else if (first_nonopt == last_nonopt)
+	    first_nonopt = optind;
+	  last_nonopt = argc;
+
+	  optind = argc;
+	}
+
+      /* If we have done all the ARGV-elements, stop the scan
+	 and back over any non-options that we skipped and permuted.  */
+
+      if (optind == argc)
+	{
+	  /* Set the next-arg-index to point at the non-options
+	     that we previously skipped, so the caller will digest them.  */
+	  if (first_nonopt != last_nonopt)
+	    optind = first_nonopt;
+	  return -1;
+	}
+
+      /* If we have come to a non-option and did not permute it,
+	 either stop the scan or describe it to the caller and pass it by.  */
+
+      if (NONOPTION_P)
+	{
+	  if (ordering == REQUIRE_ORDER)
+	    return -1;
+	  optarg = argv[optind++];
+	  return 1;
+	}
+
+      /* We have found another option-ARGV-element.
+	 Skip the initial punctuation.  */
+
+      nextchar = (argv[optind] + 1
+		  + (longopts != NULL && argv[optind][1] == '-'));
+    }
+
+  /* Decode the current option-ARGV-element.  */
+
+  /* Check whether the ARGV-element is a long option.
+
+     If long_only and the ARGV-element has the form "-f", where f is
+     a valid short option, don't consider it an abbreviated form of
+     a long option that starts with f.  Otherwise there would be no
+     way to give the -f short option.
+
+     On the other hand, if there's a long option "fubar" and
+     the ARGV-element is "-fu", do consider that an abbreviation of
+     the long option, just like "--fu", and not "-f" with arg "u".
+
+     This distinction seems to be the most useful approach.  */
+
+  if (longopts != NULL
+      && (argv[optind][1] == '-'
+	  || (long_only && (argv[optind][2] || !my_index (optstring, argv[optind][1])))))
+    {
+      char *nameend;
+      const struct option *p;
+      const struct option *pfound = NULL;
+      int exact = 0;
+      int ambig = 0;
+      int indfound = -1;
+      int option_index;
+
+      for (nameend = nextchar; *nameend && *nameend != '='; nameend++)
+	/* Do nothing.  */ ;
+
+      /* Test all long options for either exact match
+	 or abbreviated matches.  */
+      for (p = longopts, option_index = 0; p->name; p++, option_index++)
+	if (!strncmp (p->name, nextchar, nameend - nextchar))
+	  {
+	    if ((unsigned int) (nameend - nextchar)
+		== (unsigned int) strlen (p->name))
+	      {
+		/* Exact match found.  */
+		pfound = p;
+		indfound = option_index;
+		exact = 1;
+		break;
+	      }
+	    else if (pfound == NULL)
+	      {
+		/* First nonexact match found.  */
+		pfound = p;
+		indfound = option_index;
+	      }
+	    else if (long_only
+		     || pfound->has_arg != p->has_arg
+		     || pfound->flag != p->flag
+		     || pfound->val != p->val)
+	      /* Second or later nonexact match found.  */
+	      ambig = 1;
+	  }
+
+      if (ambig && !exact)
+	{
+	  if (print_errors)
+	    fprintf (stderr, _("%s: option `%s' is ambiguous\n"),
+		     argv[0], argv[optind]);
+	  nextchar += strlen (nextchar);
+	  optind++;
+	  optopt = 0;
+	  return '?';
+	}
+
+      if (pfound != NULL)
+	{
+	  option_index = indfound;
+	  optind++;
+	  if (*nameend)
+	    {
+	      /* Don't test has_arg with >, because some C compilers don't
+		 allow it to be used on enums.  */
+	      if (pfound->has_arg)
+		optarg = nameend + 1;
+	      else
+		{
+		  if (print_errors)
+		    {
+		      if (argv[optind - 1][1] == '-')
+			/* --option */
+			fprintf (stderr,
+				 _("%s: option `--%s' doesn't allow an argument\n"),
+				 argv[0], pfound->name);
+		      else
+			/* +option or -option */
+			fprintf (stderr,
+				 _("%s: option `%c%s' doesn't allow an argument\n"),
+				 argv[0], argv[optind - 1][0], pfound->name);
+		    }
+
+		  nextchar += strlen (nextchar);
+
+		  optopt = pfound->val;
+		  return '?';
+		}
+	    }
+	  else if (pfound->has_arg == 1)
+	    {
+	      if (optind < argc)
+		optarg = argv[optind++];
+	      else
+		{
+		  if (print_errors)
+		    fprintf (stderr,
+			   _("%s: option `%s' requires an argument\n"),
+			   argv[0], argv[optind - 1]);
+		  nextchar += strlen (nextchar);
+		  optopt = pfound->val;
+		  return optstring[0] == ':' ? ':' : '?';
+		}
+	    }
+	  nextchar += strlen (nextchar);
+	  if (longind != NULL)
+	    *longind = option_index;
+	  if (pfound->flag)
+	    {
+	      *(pfound->flag) = pfound->val;
+	      return 0;
+	    }
+	  return pfound->val;
+	}
+
+      /* Can't find it as a long option.  If this is not getopt_long_only,
+	 or the option starts with '--' or is not a valid short
+	 option, then it's an error.
+	 Otherwise interpret it as a short option.  */
+      if (!long_only || argv[optind][1] == '-'
+	  || my_index (optstring, *nextchar) == NULL)
+	{
+	  if (print_errors)
+	    {
+	      if (argv[optind][1] == '-')
+		/* --option */
+		fprintf (stderr, _("%s: unrecognized option `--%s'\n"),
+			 argv[0], nextchar);
+	      else
+		/* +option or -option */
+		fprintf (stderr, _("%s: unrecognized option `%c%s'\n"),
+			 argv[0], argv[optind][0], nextchar);
+	    }
+	  nextchar = (char *) "";
+	  optind++;
+	  optopt = 0;
+	  return '?';
+	}
+    }
+
+  /* Look at and handle the next short option-character.  */
+
+  {
+    char c = *nextchar++;
+    char *temp = my_index (optstring, c);
+
+    /* Increment `optind' when we start to process its last character.  */
+    if (*nextchar == '\0')
+      ++optind;
+
+    if (temp == NULL || c == ':')
+      {
+	if (print_errors)
+	  {
+	    if (posixly_correct)
+	      /* 1003.2 specifies the format of this message.  */
+	      fprintf (stderr, _("%s: illegal option -- %c\n"),
+		       argv[0], c);
+	    else
+	      fprintf (stderr, _("%s: invalid option -- %c\n"),
+		       argv[0], c);
+	  }
+	optopt = c;
+	return '?';
+      }
+    /* Convenience. Treat POSIX -W foo same as long option --foo */
+    if (temp[0] == 'W' && temp[1] == ';')
+      {
+	char *nameend;
+	const struct option *p;
+	const struct option *pfound = NULL;
+	int exact = 0;
+	int ambig = 0;
+	int indfound = 0;
+	int option_index;
+
+	/* This is an option that requires an argument.  */
+	if (*nextchar != '\0')
+	  {
+	    optarg = nextchar;
+	    /* If we end this ARGV-element by taking the rest as an arg,
+	       we must advance to the next element now.  */
+	    optind++;
+	  }
+	else if (optind == argc)
+	  {
+	    if (print_errors)
+	      {
+		/* 1003.2 specifies the format of this message.  */
+		fprintf (stderr, _("%s: option requires an argument -- %c\n"),
+			 argv[0], c);
+	      }
+	    optopt = c;
+	    if (optstring[0] == ':')
+	      c = ':';
+	    else
+	      c = '?';
+	    return c;
+	  }
+	else
+	  /* We already incremented `optind' once;
+	     increment it again when taking next ARGV-elt as argument.  */
+	  optarg = argv[optind++];
+
+	/* optarg is now the argument, see if it's in the
+	   table of longopts.  */
+
+	for (nextchar = nameend = optarg; *nameend && *nameend != '='; nameend++)
+	  /* Do nothing.  */ ;
+
+	/* Test all long options for either exact match
+	   or abbreviated matches.  */
+	for (p = longopts, option_index = 0; p->name; p++, option_index++)
+	  if (!strncmp (p->name, nextchar, nameend - nextchar))
+	    {
+	      if ((unsigned int) (nameend - nextchar) == strlen (p->name))
+		{
+		  /* Exact match found.  */
+		  pfound = p;
+		  indfound = option_index;
+		  exact = 1;
+		  break;
+		}
+	      else if (pfound == NULL)
+		{
+		  /* First nonexact match found.  */
+		  pfound = p;
+		  indfound = option_index;
+		}
+	      else
+		/* Second or later nonexact match found.  */
+		ambig = 1;
+	    }
+	if (ambig && !exact)
+	  {
+	    if (print_errors)
+	      fprintf (stderr, _("%s: option `-W %s' is ambiguous\n"),
+		       argv[0], argv[optind]);
+	    nextchar += strlen (nextchar);
+	    optind++;
+	    return '?';
+	  }
+	if (pfound != NULL)
+	  {
+	    option_index = indfound;
+	    if (*nameend)
+	      {
+		/* Don't test has_arg with >, because some C compilers don't
+		   allow it to be used on enums.  */
+		if (pfound->has_arg)
+		  optarg = nameend + 1;
+		else
+		  {
+		    if (print_errors)
+		      fprintf (stderr, _("%s: option `-W %s' doesn't allow an argument\n"),
+			       argv[0], pfound->name);
+
+		    nextchar += strlen (nextchar);
+		    return '?';
+		  }
+	      }
+	    else if (pfound->has_arg == 1)
+	      {
+		if (optind < argc)
+		  optarg = argv[optind++];
+		else
+		  {
+		    if (print_errors)
+		      fprintf (stderr,
+			       _("%s: option `%s' requires an argument\n"),
+			       argv[0], argv[optind - 1]);
+		    nextchar += strlen (nextchar);
+		    return optstring[0] == ':' ? ':' : '?';
+		  }
+	      }
+	    nextchar += strlen (nextchar);
+	    if (longind != NULL)
+	      *longind = option_index;
+	    if (pfound->flag)
+	      {
+		*(pfound->flag) = pfound->val;
+		return 0;
+	      }
+	    return pfound->val;
+	  }
+	  nextchar = NULL;
+	  return 'W';	/* Let the application handle it.   */
+      }
+    if (temp[1] == ':')
+      {
+	if (temp[2] == ':')
+	  {
+	    /* This is an option that accepts an argument optionally.  */
+	    if (*nextchar != '\0')
+	      {
+		optarg = nextchar;
+		optind++;
+	      }
+	    else
+	      optarg = NULL;
+	    nextchar = NULL;
+	  }
+	else
+	  {
+	    /* This is an option that requires an argument.  */
+	    if (*nextchar != '\0')
+	      {
+		optarg = nextchar;
+		/* If we end this ARGV-element by taking the rest as an arg,
+		   we must advance to the next element now.  */
+		optind++;
+	      }
+	    else if (optind == argc)
+	      {
+		if (print_errors)
+		  {
+		    /* 1003.2 specifies the format of this message.  */
+		    fprintf (stderr,
+			     _("%s: option requires an argument -- %c\n"),
+			     argv[0], c);
+		  }
+		optopt = c;
+		if (optstring[0] == ':')
+		  c = ':';
+		else
+		  c = '?';
+	      }
+	    else
+	      /* We already incremented `optind' once;
+		 increment it again when taking next ARGV-elt as argument.  */
+	      optarg = argv[optind++];
+	    nextchar = NULL;
+	  }
+      }
+    return c;
+  }
+}
+
+int
+getopt (argc, argv, optstring)
+     int argc;
+     char *const *argv;
+     const char *optstring;
+{
+  return _getopt_internal (argc, argv, optstring,
+			   (const struct option *) 0,
+			   (int *) 0,
+			   0);
+}
+
+#endif	/* Not ELIDE_CODE.  */
+
+#ifdef TEST
+
+/* Compile with -DTEST to make an executable for use in testing
+   the above definition of `getopt'.  */
+
+int
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  int c;
+  int digit_optind = 0;
+
+  while (1)
+    {
+      int this_option_optind = optind ? optind : 1;
+
+      c = getopt (argc, argv, "abc:d:0123456789");
+      if (c == -1)
+	break;
+
+      switch (c)
+	{
+	case '0':
+	case '1':
+	case '2':
+	case '3':
+	case '4':
+	case '5':
+	case '6':
+	case '7':
+	case '8':
+	case '9':
+	  if (digit_optind != 0 && digit_optind != this_option_optind)
+	    printf ("digits occur in two different argv-elements.\n");
+	  digit_optind = this_option_optind;
+	  printf ("option %c\n", c);
+	  break;
+
+	case 'a':
+	  printf ("option a\n");
+	  break;
+
+	case 'b':
+	  printf ("option b\n");
+	  break;
+
+	case 'c':
+	  printf ("option c with value `%s'\n", optarg);
+	  break;
+
+	case '?':
+	  break;
+
+	default:
+	  printf ("?? getopt returned character code 0%o ??\n", c);
+	}
+    }
+
+  if (optind < argc)
+    {
+      printf ("non-option ARGV-elements: ");
+      while (optind < argc)
+	printf ("%s ", argv[optind++]);
+      printf ("\n");
+    }
+
+  exit (0);
+}
+
+#endif /* TEST */
diff --git a/Build/source/libs/potrace/potrace-src/src/getopt.h b/Build/source/libs/potrace/potrace-src/src/getopt.h
new file mode 100644
index 00000000000..20daef6168b
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/getopt.h
@@ -0,0 +1,180 @@
+/* Declarations for getopt.
+   Copyright (C) 1989,90,91,92,93,94,96,97,98,99 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.  */
+
+#ifndef _GETOPT_H
+
+#ifndef __need_getopt
+# define _GETOPT_H 1
+#endif
+
+/* If __GNU_LIBRARY__ is not already defined, either we are being used
+   standalone, or this is the first header included in the source file.
+   If we are being used with glibc, we need to include <features.h>, but
+   that does not exist if we are standalone.  So: if __GNU_LIBRARY__ is
+   not defined, include <ctype.h>, which will pull in <features.h> for us
+   if it's from glibc.  (Why ctype.h?  It's guaranteed to exist and it
+   doesn't flood the namespace with stuff the way some other headers do.)  */
+#if !defined __GNU_LIBRARY__
+# include <ctype.h>
+#endif
+
+#ifdef	__cplusplus
+extern "C" {
+#endif
+
+/* For communication from `getopt' to the caller.
+   When `getopt' finds an option that takes an argument,
+   the argument value is returned here.
+   Also, when `ordering' is RETURN_IN_ORDER,
+   each non-option ARGV-element is returned here.  */
+
+extern char *optarg;
+
+/* Index in ARGV of the next element to be scanned.
+   This is used for communication to and from the caller
+   and for communication between successive calls to `getopt'.
+
+   On entry to `getopt', zero means this is the first call; initialize.
+
+   When `getopt' returns -1, this is the index of the first of the
+   non-option elements that the caller should itself scan.
+
+   Otherwise, `optind' communicates from one call to the next
+   how much of ARGV has been scanned so far.  */
+
+extern int optind;
+
+/* Callers store zero here to inhibit the error message `getopt' prints
+   for unrecognized options.  */
+
+extern int opterr;
+
+/* Set to an option character which was unrecognized.  */
+
+extern int optopt;
+
+#ifndef __need_getopt
+/* Describe the long-named options requested by the application.
+   The LONG_OPTIONS argument to getopt_long or getopt_long_only is a vector
+   of `struct option' terminated by an element containing a name which is
+   zero.
+
+   The field `has_arg' is:
+   no_argument		(or 0) if the option does not take an argument,
+   required_argument	(or 1) if the option requires an argument,
+   optional_argument 	(or 2) if the option takes an optional argument.
+
+   If the field `flag' is not NULL, it points to a variable that is set
+   to the value given in the field `val' when the option is found, but
+   left unchanged if the option is not found.
+
+   To have a long-named option do something other than set an `int' to
+   a compiled-in constant, such as set a value from `optarg', set the
+   option's `flag' field to zero and its `val' field to a nonzero
+   value (the equivalent single-letter option character, if there is
+   one).  For long options that have a zero `flag' field, `getopt'
+   returns the contents of the `val' field.  */
+
+struct option
+{
+# if defined __STDC__ && __STDC__
+  const char *name;
+# else
+  char *name;
+# endif
+  /* has_arg can't be an enum because some compilers complain about
+     type mismatches in all the code that assumes it is an int.  */
+  int has_arg;
+  int *flag;
+  int val;
+};
+
+/* Names for the values of the `has_arg' field of `struct option'.  */
+
+# define no_argument		0
+# define required_argument	1
+# define optional_argument	2
+#endif	/* need getopt */
+
+
+/* Get definitions and prototypes for functions to process the
+   arguments in ARGV (ARGC of them, minus the program name) for
+   options given in OPTS.
+
+   Return the option character from OPTS just read.  Return -1 when
+   there are no more options.  For unrecognized options, or options
+   missing arguments, `optopt' is set to the option letter, and '?' is
+   returned.
+
+   The OPTS string is a list of characters which are recognized option
+   letters, optionally followed by colons, specifying that that letter
+   takes an argument, to be placed in `optarg'.
+
+   If a letter in OPTS is followed by two colons, its argument is
+   optional.  This behavior is specific to the GNU `getopt'.
+
+   The argument `--' causes premature termination of argument
+   scanning, explicitly telling `getopt' that there are no more
+   options.
+
+   If OPTS begins with `--', then non-option arguments are treated as
+   arguments to the option '\0'.  This behavior is specific to the GNU
+   `getopt'.  */
+
+#if defined __STDC__ && __STDC__
+# ifdef __GNU_LIBRARY__
+/* Many other libraries have conflicting prototypes for getopt, with
+   differences in the consts, in stdlib.h.  To avoid compilation
+   errors, only prototype getopt for the GNU C library.  */
+extern int getopt (int argc, char *const *argv, const char *shortopts);
+# else /* not __GNU_LIBRARY__ */
+extern int getopt ();
+# endif /* __GNU_LIBRARY__ */
+
+# ifndef __need_getopt
+extern int getopt_long (int argc, char *const *argv, const char *shortopts,
+		        const struct option *longopts, int *longind);
+extern int getopt_long_only (int argc, char *const *argv,
+			     const char *shortopts,
+		             const struct option *longopts, int *longind);
+
+/* Internal only.  Users should not call this directly.  */
+extern int _getopt_internal (int argc, char *const *argv,
+			     const char *shortopts,
+		             const struct option *longopts, int *longind,
+			     int long_only);
+# endif
+#else /* not __STDC__ */
+extern int getopt ();
+# ifndef __need_getopt
+extern int getopt_long ();
+extern int getopt_long_only ();
+
+extern int _getopt_internal ();
+# endif
+#endif /* __STDC__ */
+
+#ifdef	__cplusplus
+}
+#endif
+
+/* Make sure we later can get all the definitions and declarations.  */
+#undef __need_getopt
+
+#endif /* getopt.h */
diff --git a/Build/source/libs/potrace/potrace-src/src/getopt1.c b/Build/source/libs/potrace/potrace-src/src/getopt1.c
new file mode 100644
index 00000000000..8ffe0e6ad71
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/getopt1.c
@@ -0,0 +1,188 @@
+/* getopt_long and getopt_long_only entry points for GNU getopt.
+   Copyright (C) 1987,88,89,90,91,92,93,94,96,97,98
+     Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+   Boston, MA 02110-1301, USA.  */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "getopt.h"
+
+#if !defined __STDC__ || !__STDC__
+/* This is a separate conditional since some stdc systems
+   reject `defined (const)'.  */
+#ifndef const
+#define const
+#endif
+#endif
+
+#include <stdio.h>
+
+/* Comment out all this code if we are using the GNU C Library, and are not
+   actually compiling the library itself.  This code is part of the GNU C
+   Library, but also included in many other GNU distributions.  Compiling
+   and linking in this code is a waste when using the GNU C library
+   (especially if it is a shared library).  Rather than having every GNU
+   program understand `configure --with-gnu-libc' and omit the object files,
+   it is simpler to just do this in the source for each such file.  */
+
+#define GETOPT_INTERFACE_VERSION 2
+#if !defined _LIBC && defined __GLIBC__ && __GLIBC__ >= 2
+#include <gnu-versions.h>
+#if _GNU_GETOPT_INTERFACE_VERSION == GETOPT_INTERFACE_VERSION
+#define ELIDE_CODE
+#endif
+#endif
+
+#ifndef ELIDE_CODE
+
+
+/* This needs to come after some library #include
+   to get __GNU_LIBRARY__ defined.  */
+#ifdef __GNU_LIBRARY__
+#include <stdlib.h>
+#endif
+
+#ifndef	NULL
+#define NULL 0
+#endif
+
+int
+getopt_long (argc, argv, options, long_options, opt_index)
+     int argc;
+     char *const *argv;
+     const char *options;
+     const struct option *long_options;
+     int *opt_index;
+{
+  return _getopt_internal (argc, argv, options, long_options, opt_index, 0);
+}
+
+/* Like getopt_long, but '-' as well as '--' can indicate a long option.
+   If an option that starts with '-' (not '--') doesn't match a long option,
+   but does match a short option, it is parsed as a short option
+   instead.  */
+
+int
+getopt_long_only (argc, argv, options, long_options, opt_index)
+     int argc;
+     char *const *argv;
+     const char *options;
+     const struct option *long_options;
+     int *opt_index;
+{
+  return _getopt_internal (argc, argv, options, long_options, opt_index, 1);
+}
+
+
+#endif	/* Not ELIDE_CODE.  */
+
+#ifdef TEST
+
+#include <stdio.h>
+
+int
+main (argc, argv)
+     int argc;
+     char **argv;
+{
+  int c;
+  int digit_optind = 0;
+
+  while (1)
+    {
+      int this_option_optind = optind ? optind : 1;
+      int option_index = 0;
+      static struct option long_options[] =
+      {
+	{"add", 1, 0, 0},
+	{"append", 0, 0, 0},
+	{"delete", 1, 0, 0},
+	{"verbose", 0, 0, 0},
+	{"create", 0, 0, 0},
+	{"file", 1, 0, 0},
+	{0, 0, 0, 0}
+      };
+
+      c = getopt_long (argc, argv, "abc:d:0123456789",
+		       long_options, &option_index);
+      if (c == -1)
+	break;
+
+      switch (c)
+	{
+	case 0:
+	  printf ("option %s", long_options[option_index].name);
+	  if (optarg)
+	    printf (" with arg %s", optarg);
+	  printf ("\n");
+	  break;
+
+	case '0':
+	case '1':
+	case '2':
+	case '3':
+	case '4':
+	case '5':
+	case '6':
+	case '7':
+	case '8':
+	case '9':
+	  if (digit_optind != 0 && digit_optind != this_option_optind)
+	    printf ("digits occur in two different argv-elements.\n");
+	  digit_optind = this_option_optind;
+	  printf ("option %c\n", c);
+	  break;
+
+	case 'a':
+	  printf ("option a\n");
+	  break;
+
+	case 'b':
+	  printf ("option b\n");
+	  break;
+
+	case 'c':
+	  printf ("option c with value `%s'\n", optarg);
+	  break;
+
+	case 'd':
+	  printf ("option d with value `%s'\n", optarg);
+	  break;
+
+	case '?':
+	  break;
+
+	default:
+	  printf ("?? getopt returned character code 0%o ??\n", c);
+	}
+    }
+
+  if (optind < argc)
+    {
+      printf ("non-option ARGV-elements: ");
+      while (optind < argc)
+	printf ("%s ", argv[optind++]);
+      printf ("\n");
+    }
+
+  exit (0);
+}
+
+#endif /* TEST */
diff --git a/Build/source/libs/potrace/potrace-src/src/greymap.c b/Build/source/libs/potrace/potrace-src/src/greymap.c
new file mode 100644
index 00000000000..ad8e5d7e303
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/greymap.c
@@ -0,0 +1,948 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* Routines for manipulating greymaps, including reading pgm files. We
+   only deal with greymaps of depth 8 bits. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <math.h>
+#include <errno.h>
+#include <stddef.h>
+
+#include "greymap.h"
+#include "bitops.h"
+
+#define INTBITS (8*sizeof(int))
+
+#define mod(a,n) ((a)>=(n) ? (a)%(n) : (a)>=0 ? (a) : (n)-1-(-1-(a))%(n))
+
+static int gm_readbody_pnm(FILE *f, greymap_t **gmp, int magic);
+static int gm_readbody_bmp(FILE *f, greymap_t **gmp);
+
+/* ---------------------------------------------------------------------- */
+/* basic greymap routines */
+
+/* return new un-initialized greymap. NULL with errno on error.
+   Assumes w, h >= 0. */
+greymap_t *gm_new(int w, int h) {
+  greymap_t *gm;
+  ptrdiff_t size = (ptrdiff_t)w * (ptrdiff_t)h * (ptrdiff_t)sizeof(signed short int);
+  
+  /* check for overflow error */
+  if (size < 0 || size / w / h != sizeof(signed short int)) {
+    errno = ENOMEM;
+    return NULL;
+  }
+
+  gm = (greymap_t *) malloc(sizeof(greymap_t));
+  if (!gm) {
+    return NULL;
+  }
+  gm->w = w;
+  gm->h = h;
+  gm->map = (signed short int *) malloc(size);
+  if (!gm->map) {
+    free(gm);
+    return NULL;
+  }
+  return gm;
+}
+
+/* free the given greymap */
+void gm_free(greymap_t *gm) {
+  if (gm) {
+    free(gm->map);
+  }
+  free(gm);
+}
+
+/* duplicate the given greymap. Return NULL on error with errno set. */
+greymap_t *gm_dup(greymap_t *gm) {
+  greymap_t *gm1 = gm_new(gm->w, gm->h);
+  if (!gm1) {
+    return NULL;
+  }
+  memcpy(gm1->map, gm->map, gm->w*gm->h*sizeof(signed short int));
+  return gm1;
+}
+
+/* clear the given greymap to color b. */
+void gm_clear(greymap_t *gm, int b) {
+  int i;
+
+  if (b==0) {
+    memset(gm->map, 0, gm->w*gm->h*sizeof(signed short int));
+  } else {
+    for (i=0; i<gm->w*gm->h; i++) {
+      gm->map[i] = b;
+    }
+  }    
+}
+
+/* ---------------------------------------------------------------------- */
+/* routines for reading pnm streams */
+
+/* read next character after whitespace and comments. Return EOF on
+   end of file or error. */
+static int fgetc_ws(FILE *f) {
+  int c;
+
+  while (1) {
+    c = fgetc(f);
+    if (c=='#') {
+      while (1) {
+	c = fgetc(f);
+	if (c=='\n' || c==EOF) {
+	  break;
+	}
+      }
+    }
+    /* space, tab, line feed, carriage return, form-feed */
+    if (c!=' ' && c!='\t' && c!='\r' && c!='\n' && c!=12) {
+      return c;
+    }
+  }
+}
+
+/* skip whitespace and comments, then read a non-negative decimal
+   number from a stream. Return -1 on EOF. Tolerate other errors (skip
+   bad characters). Do not the read any characters following the
+   number (put next character back into the stream) */
+
+static int readnum(FILE *f) {
+  int c;
+  int acc;
+
+  /* skip whitespace and comments */
+  while (1) {
+    c = fgetc_ws(f);
+    if (c==EOF) {
+      return -1;
+    }
+    if (c>='0' && c<='9') {
+      break;
+    }
+  }
+
+  /* first digit is already in c */
+  acc = c-'0';
+  while (1) {
+    c = fgetc(f);
+    if (c==EOF) {
+      break;
+    }
+    if (c<'0' || c>'9') {
+      ungetc(c, f);
+      break;
+    }
+    acc *= 10;
+    acc += c-'0';
+  }
+  return acc;
+}
+
+/* similar to readnum, but read only a single 0 or 1, and do not read
+   any characters after it. */
+
+static int readbit(FILE *f) {
+  int c;
+
+  /* skip whitespace and comments */
+  while (1) {
+    c = fgetc_ws(f);
+    if (c==EOF) {
+      return -1;
+    }
+    if (c>='0' && c<='1') {
+      break;
+    }
+  }
+
+  return c-'0';
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* read a PNM stream: P1-P6 format (see pnm(5)), or a BMP stream, and
+   convert the output to a greymap. Return greymap in *gmp. Return 0
+   on success, -1 on error with errno set, -2 on bad file format (with
+   error message in gm_read_error), and 1 on premature end of file, -3
+   on empty file (including files with only whitespace and comments),
+   -4 if wrong magic number. If the return value is >=0, *gmp is
+   valid. */
+
+char *gm_read_error = NULL;
+
+int gm_read(FILE *f, greymap_t **gmp) {
+  int magic[2];
+
+  /* read magic number. We ignore whitespace and comments before the
+     magic, for the benefit of concatenated files in P1-P3 format.
+     Multiple P1-P3 images in a single file are not formally allowed
+     by the PNM standard, but there is no harm in being lenient. */
+
+  magic[0] = fgetc_ws(f);
+  if (magic[0] == EOF) {
+    /* files which contain only comments and whitespace count as "empty" */
+    return -3;
+  } 
+  magic[1] = fgetc(f);
+  if (magic[0] == 'P' && magic[1] >= '1' && magic[1] <= '6') {
+    return gm_readbody_pnm(f, gmp, magic[1]);
+  }
+  if (magic[0] == 'B' && magic[1] == 'M') {
+    return gm_readbody_bmp(f, gmp);
+  }
+  return -4;
+}
+
+/* ---------------------------------------------------------------------- */
+/* read PNM format */
+
+/* read PNM stream after magic number. Return values as for gm_read */
+static int gm_readbody_pnm(FILE *f, greymap_t **gmp, int magic) {
+  greymap_t *gm;
+  int x, y, i, j, b, b1, sum;
+  int bpr; /* bytes per row (as opposed to 4*gm->c) */
+  int w, h, max;
+
+  gm = NULL;
+
+  w = readnum(f);
+  if (w<0) {
+    goto format_error;
+  }
+
+  h = readnum(f);
+  if (h<0) {
+    goto format_error;
+  }
+
+  /* allocate greymap */
+  gm = gm_new(w, h);
+  if (!gm) {
+    return -1;
+  }
+
+  /* zero it out */
+  gm_clear(gm, 0);
+
+  switch (magic) {
+  default: 
+    /* not reached */
+    goto format_error;  
+
+  case '1':
+    /* read P1 format: PBM ascii */
+    
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+	b = readbit(f);
+	if (b<0) {
+	  goto eof;
+	}
+	GM_UPUT(gm, x, y, b ? 0 : 255);
+      }
+    }
+    break;
+
+  case '2':
+    /* read P2 format: PGM ascii */
+    
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+    
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+        b = readnum(f);
+        if (b<0) {
+          goto eof;
+        }
+        GM_UPUT(gm, x, y, b*255/max);
+      }
+    }
+    break;
+
+  case '3':
+    /* read P3 format: PPM ascii */
+    
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+    
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+	sum = 0;
+	for (i=0; i<3; i++) {
+	  b = readnum(f);
+	  if (b<0) {
+	    goto eof;
+	  }
+	  sum += b;
+	}
+        GM_UPUT(gm, x, y, sum*(255/3)/max);
+      }
+    }
+    break;
+
+  case '4':
+    /* read P4 format: PBM raw */
+
+    b = fgetc(f);  /* read single white-space character after height */
+    if (b==EOF) {
+      goto format_error;
+    }
+
+    bpr = (w+7)/8;
+
+    for (y=h-1; y>=0; y--) {
+      for (i=0; i<bpr; i++) {
+	b = fgetc(f);
+	if (b==EOF) {
+	  goto eof;
+	}
+	for (j=0; j<8; j++) {
+	  GM_PUT(gm, i*8+j, y, b & (0x80 >> j) ? 0 : 255);
+	}
+      }
+    }
+    break;
+
+  case '5':
+    /* read P5 format: PGM raw */
+
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+
+    b = fgetc(f);  /* read single white-space character after max */
+    if (b==EOF) {
+      goto format_error;
+    }
+
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+        b = fgetc(f);
+        if (b==EOF)
+          goto eof;
+        if (max>=256) {
+          b <<= 8;
+          b1 = fgetc(f);
+          if (b1==EOF)
+            goto eof;
+          b |= b1;
+        }
+        GM_UPUT(gm, x, y, b*255/max);
+      }
+    }
+    break;
+
+  case '6':
+    /* read P6 format: PPM raw */
+
+    max = readnum(f);
+    if (max<1) {
+      goto format_error;
+    }
+
+    b = fgetc(f);  /* read single white-space character after max */
+    if (b==EOF) {
+      goto format_error;
+    }
+
+    for (y=h-1; y>=0; y--) {
+      for (x=0; x<w; x++) {
+        sum = 0;
+        for (i=0; i<3; i++) {
+          b = fgetc(f);
+          if (b==EOF) {
+            goto eof;
+	  }
+          if (max>=256) {
+            b <<= 8;
+            b1 = fgetc(f);
+            if (b1==EOF)
+              goto eof;
+            b |= b1;
+          }
+          sum += b;
+        }
+        GM_UPUT(gm, x, y, sum*(255/3)/max);
+      }
+    }
+    break;
+  }
+
+  *gmp = gm;
+  return 0;
+
+ eof:
+  *gmp = gm;
+  return 1;
+
+ format_error:
+  gm_free(gm);
+  if (magic == '1' || magic == '4') {
+    gm_read_error = "invalid pbm file";
+  } else if (magic == '2' || magic == '5') {
+    gm_read_error = "invalid pgm file";
+  } else {
+    gm_read_error = "invalid ppm file";
+  }
+  return -2;
+}
+
+/* ---------------------------------------------------------------------- */
+/* read BMP format */
+
+struct bmp_info_s {
+  unsigned int FileSize;
+  unsigned int reserved;
+  unsigned int DataOffset;
+  unsigned int InfoSize;
+  unsigned int w;              /* width */
+  unsigned int h;              /* height */
+  unsigned int Planes;
+  unsigned int bits;           /* bits per sample */
+  unsigned int comp;           /* compression mode */
+  unsigned int ImageSize;
+  unsigned int XpixelsPerM;
+  unsigned int YpixelsPerM;
+  unsigned int ncolors;        /* number of colors in palette */
+  unsigned int ColorsImportant;
+  unsigned int RedMask;
+  unsigned int GreenMask;
+  unsigned int BlueMask;
+  unsigned int AlphaMask;
+  unsigned int ctbits;         /* sample size for color table */
+  int topdown;                 /* top-down mode? */
+};
+typedef struct bmp_info_s bmp_info_t;
+
+/* auxiliary */
+
+static int bmp_count = 0; /* counter for byte padding */
+static int bmp_pos = 0;   /* counter from start of BMP data */
+
+/* read n-byte little-endian integer. Return 1 on EOF or error, else
+   0. Assume n<=4. */
+static int bmp_readint(FILE *f, int n, unsigned int *p) {
+  int i;
+  unsigned int sum = 0;
+  int b;
+
+  for (i=0; i<n; i++) {
+    b = fgetc(f);
+    if (b==EOF) {
+      return 1;
+    }
+    sum += b << (8*i);
+  }
+  bmp_count += n;
+  bmp_pos += n;
+  *p = sum;
+  return 0;
+}
+
+/* reset padding boundary */
+static void bmp_pad_reset(void) {
+  bmp_count = 0;
+}
+
+/* read padding bytes to 4-byte boundary. Return 1 on EOF or error,
+   else 0. */
+static int bmp_pad(FILE *f) {
+  int c, i, b;
+
+  c = (-bmp_count) & 3;
+  for (i=0; i<c; i++) {
+    b = fgetc(f);
+    if (b==EOF) {
+      return 1;
+    }
+  }
+  bmp_pos += c;
+  bmp_count = 0;
+  return 0;
+}
+  
+/* forward to the new file position. Return 1 on EOF or error, else 0 */
+static int bmp_forward(FILE *f, int pos) {
+  int b;
+
+  while (bmp_pos < pos) {
+    b = fgetc(f);
+    if (b==EOF) {
+      return 1;
+    }
+    bmp_pos++;
+    bmp_count++;
+  }
+  return 0;
+}
+
+#define TRY(x) if (x) goto try_error
+#define TRY_EOF(x) if (x) goto eof
+
+/* correct y-coordinate for top-down format */
+#define ycorr(y) (bmpinfo.topdown ? bmpinfo.h-1-y : y)
+
+/* read BMP stream after magic number. Return values as for gm_read.
+   We choose to be as permissive as possible, since there are many
+   programs out there which produce BMP. For instance, ppmtobmp can
+   produce codings with anywhere from 1-8 or 24 bits per sample,
+   although most specifications only allow 1,4,8,24,32. We can also
+   read both the old and new OS/2 BMP formats in addition to the
+   Windows BMP format. */
+static int gm_readbody_bmp(FILE *f, greymap_t **gmp) {
+  bmp_info_t bmpinfo;
+  int *coltable;
+  unsigned int b, c;
+  unsigned int i, j;
+  greymap_t *gm;
+  unsigned int x, y;
+  int col[2];
+  unsigned int bitbuf;
+  unsigned int n;
+  unsigned int redshift, greenshift, blueshift;
+
+  gm_read_error = NULL;
+  gm = NULL;
+  coltable = NULL;
+
+  bmp_pos = 2;  /* set file position */
+
+  /* file header (minus magic number) */
+  TRY(bmp_readint(f, 4, &bmpinfo.FileSize));
+  TRY(bmp_readint(f, 4, &bmpinfo.reserved));
+  TRY(bmp_readint(f, 4, &bmpinfo.DataOffset));
+
+  /* info header */
+  TRY(bmp_readint(f, 4, &bmpinfo.InfoSize));
+  if (bmpinfo.InfoSize == 40 || bmpinfo.InfoSize == 64
+      || bmpinfo.InfoSize == 108 || bmpinfo.InfoSize == 124) {
+    /* Windows or new OS/2 format */
+    bmpinfo.ctbits = 32; /* sample size in color table */
+    TRY(bmp_readint(f, 4, &bmpinfo.w));
+    TRY(bmp_readint(f, 4, &bmpinfo.h));
+    TRY(bmp_readint(f, 2, &bmpinfo.Planes));
+    TRY(bmp_readint(f, 2, &bmpinfo.bits));
+    TRY(bmp_readint(f, 4, &bmpinfo.comp));
+    TRY(bmp_readint(f, 4, &bmpinfo.ImageSize));
+    TRY(bmp_readint(f, 4, &bmpinfo.XpixelsPerM));
+    TRY(bmp_readint(f, 4, &bmpinfo.YpixelsPerM));
+    TRY(bmp_readint(f, 4, &bmpinfo.ncolors));
+    TRY(bmp_readint(f, 4, &bmpinfo.ColorsImportant));
+    if (bmpinfo.InfoSize >= 108) { /* V4 and V5 bitmaps */
+      TRY(bmp_readint(f, 4, &bmpinfo.RedMask));
+      TRY(bmp_readint(f, 4, &bmpinfo.GreenMask));
+      TRY(bmp_readint(f, 4, &bmpinfo.BlueMask));
+      TRY(bmp_readint(f, 4, &bmpinfo.AlphaMask));
+    }
+    if (bmpinfo.w > 0x7fffffff) {
+      goto format_error;
+    }
+    if (bmpinfo.h > 0x7fffffff) {
+      bmpinfo.h = (-bmpinfo.h) & 0xffffffff;
+      bmpinfo.topdown = 1;
+    } else {
+      bmpinfo.topdown = 0;
+    }
+    if (bmpinfo.h > 0x7fffffff) {
+      goto format_error;
+    }
+  } else if (bmpinfo.InfoSize == 12) {
+    /* old OS/2 format */
+    bmpinfo.ctbits = 24; /* sample size in color table */
+    TRY(bmp_readint(f, 2, &bmpinfo.w));
+    TRY(bmp_readint(f, 2, &bmpinfo.h));
+    TRY(bmp_readint(f, 2, &bmpinfo.Planes));
+    TRY(bmp_readint(f, 2, &bmpinfo.bits));
+    bmpinfo.comp = 0;
+    bmpinfo.ncolors = 0;
+    bmpinfo.topdown = 0;
+  } else {
+    goto format_error;
+  }
+
+  if (bmpinfo.comp == 3 && bmpinfo.InfoSize < 108) {
+    /* bitfield feature is only understood with V4 and V5 format */
+    goto format_error;
+  }
+
+  /* forward to color table (e.g., if bmpinfo.InfoSize == 64) */
+  TRY(bmp_forward(f, 14+bmpinfo.InfoSize));
+
+  if (bmpinfo.Planes != 1) {
+    gm_read_error = "cannot handle bmp planes";
+    goto format_error;  /* can't handle planes */
+  }
+  
+  if (bmpinfo.ncolors == 0) {
+    bmpinfo.ncolors = 1 << bmpinfo.bits;
+  }
+
+  /* color table, present only if bmpinfo.bits <= 8. */
+  if (bmpinfo.bits <= 8) {
+    coltable = (int *) calloc(bmpinfo.ncolors, sizeof(int));
+    if (!coltable) {
+      goto std_error;
+    }
+    /* NOTE: since we are reading a greymap, we can immediately convert
+       the color table entries to grey values. */
+    for (i=0; i<bmpinfo.ncolors; i++) {
+      TRY(bmp_readint(f, bmpinfo.ctbits/8, &c));
+      c = ((c>>16) & 0xff) + ((c>>8) & 0xff) + (c & 0xff);
+      coltable[i] = c/3;
+    }
+  }
+
+  /* forward to data */
+  if (bmpinfo.InfoSize != 12) { /* not old OS/2 format */
+    TRY(bmp_forward(f, bmpinfo.DataOffset));
+  }
+
+  /* allocate greymap */
+  gm = gm_new(bmpinfo.w, bmpinfo.h);
+  if (!gm) {
+    goto std_error;
+  }
+  
+  /* zero it out */
+  gm_clear(gm, 0);
+
+  switch (bmpinfo.bits + 0x100*bmpinfo.comp) {
+    
+  default:
+    goto format_error;
+    break;
+    
+  case 0x001:  /* monochrome palette */
+
+    /* raster data */
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      for (i=0; 8*i<bmpinfo.w; i++) {
+	TRY_EOF(bmp_readint(f, 1, &b));
+	for (j=0; j<8; j++) {
+	  GM_PUT(gm, i*8+j, ycorr(y), b & (0x80 >> j) ? coltable[1] : coltable[0]);
+	}
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+   
+  case 0x002:  /* 2-bit to 8-bit palettes */
+  case 0x003: 
+  case 0x004: 
+  case 0x005: 
+  case 0x006: 
+  case 0x007: 
+  case 0x008:
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      bitbuf = 0;  /* bit buffer: bits in buffer are high-aligned */
+      n = 0;       /* number of bits currently in bitbuffer */
+      for (x=0; x<bmpinfo.w; x++) {
+	if (n < bmpinfo.bits) {
+	  TRY_EOF(bmp_readint(f, 1, &b));
+	  bitbuf |= b << (INTBITS - 8 - n);
+	  n += 8;
+	}
+	b = bitbuf >> (INTBITS - bmpinfo.bits);
+	bitbuf <<= bmpinfo.bits;
+	n -= bmpinfo.bits;
+	GM_UPUT(gm, x, ycorr(y), coltable[b]);
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+
+  case 0x010:  /* 16-bit encoding */
+    /* can't do this format because it is not well-documented and I
+       don't have any samples */
+    gm_read_error = "cannot handle bmp 16-bit coding";
+    goto format_error;
+    break;
+
+  case 0x018:  /* 24-bit encoding */
+  case 0x020:  /* 32-bit encoding */
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      for (x=0; x<bmpinfo.w; x++) {
+        TRY_EOF(bmp_readint(f, bmpinfo.bits/8, &c));
+	c = ((c>>16) & 0xff) + ((c>>8) & 0xff) + (c & 0xff);
+        GM_UPUT(gm, x, ycorr(y), c/3);
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+
+  case 0x320:  /* 32-bit encoding with bitfields */
+    redshift = lobit(bmpinfo.RedMask);
+    greenshift = lobit(bmpinfo.GreenMask);
+    blueshift = lobit(bmpinfo.BlueMask);
+
+    for (y=0; y<bmpinfo.h; y++) {
+      bmp_pad_reset();
+      for (x=0; x<bmpinfo.w; x++) {
+        TRY_EOF(bmp_readint(f, bmpinfo.bits/8, &c));
+	c = ((c & bmpinfo.RedMask) >> redshift) + ((c & bmpinfo.GreenMask) >> greenshift) + ((c & bmpinfo.BlueMask) >> blueshift);
+        GM_UPUT(gm, x, ycorr(y), c/3);
+      }
+      TRY(bmp_pad(f));
+    }
+    break;
+
+  case 0x204:  /* 4-bit runlength compressed encoding (RLE4) */
+    x = 0;
+    y = 0;
+    while (1) {
+      TRY_EOF(bmp_readint(f, 1, &b)); /* opcode */
+      TRY_EOF(bmp_readint(f, 1, &c)); /* argument */
+      if (b>0) {
+	/* repeat count */
+	col[0] = coltable[(c>>4) & 0xf];
+	col[1] = coltable[c & 0xf];
+	for (i=0; i<b && x<bmpinfo.w; i++) {
+	  if (x>=bmpinfo.w) {
+	    x=0;
+	    y++;
+	  }
+	  if (y>=bmpinfo.h) {
+	    break;
+	  }
+	  GM_UPUT(gm, x, ycorr(y), col[i&1]);
+	  x++;
+	}
+      } else if (c == 0) {
+	/* end of line */
+	y++;
+	x = 0;
+      } else if (c == 1) {
+	/* end of greymap */
+	break;
+      } else if (c == 2) {
+	/* "delta": skip pixels in x and y directions */
+	TRY_EOF(bmp_readint(f, 1, &b)); /* x offset */
+	TRY_EOF(bmp_readint(f, 1, &c)); /* y offset */
+	x += b;
+	y += c;
+      } else {
+	/* verbatim segment */
+	for (i=0; i<c; i++) {
+	  if ((i&1)==0) {
+	    TRY_EOF(bmp_readint(f, 1, &b));
+	  }
+	  if (x>=bmpinfo.w) {
+	    x=0;
+	    y++;
+	  }
+	  if (y>=bmpinfo.h) {
+	    break;
+	  }
+	  GM_PUT(gm, x, ycorr(y), coltable[(b>>(4-4*(i&1))) & 0xf]);
+	  x++;
+	}
+	if ((c+1) & 2) {
+	  /* pad to 16-bit boundary */
+	  TRY_EOF(bmp_readint(f, 1, &b));
+	}
+      }
+    }
+    break;
+
+  case 0x108:  /* 8-bit runlength compressed encoding (RLE8) */
+    x = 0;
+    y = 0;
+    while (1) {
+      TRY_EOF(bmp_readint(f, 1, &b)); /* opcode */
+      TRY_EOF(bmp_readint(f, 1, &c)); /* argument */
+      if (b>0) {
+	/* repeat count */
+	for (i=0; i<b; i++) {
+	  if (x>=bmpinfo.w) {
+	    x=0;
+	    y++;
+	  }
+	  if (y>=bmpinfo.h) {
+	    break;
+	  }
+	  GM_UPUT(gm, x, ycorr(y), coltable[c]);
+	  x++;
+	}
+      } else if (c == 0) {
+	/* end of line */
+	y++;
+	x = 0;
+      } else if (c == 1) {
+	/* end of greymap */
+	break;
+      } else if (c == 2) {
+	/* "delta": skip pixels in x and y directions */
+	TRY_EOF(bmp_readint(f, 1, &b)); /* x offset */
+	TRY_EOF(bmp_readint(f, 1, &c)); /* y offset */
+	x += b;
+	y += c;
+      } else {
+	/* verbatim segment */
+	for (i=0; i<c; i++) {
+	  TRY_EOF(bmp_readint(f, 1, &b));
+          if (x>=bmpinfo.w) {
+            x=0;
+            y++;
+          }
+          if (y>=bmpinfo.h) {
+            break;
+          }
+	  GM_PUT(gm, x, ycorr(y), coltable[b]);
+	  x++;
+	}
+	if (c & 1) {
+	  /* pad input to 16-bit boundary */
+	  TRY_EOF(bmp_readint(f, 1, &b));
+	}
+      }
+    }
+    break;
+
+  } /* switch */
+
+  /* skip any potential junk after the data section, but don't
+     complain in case EOF is encountered */
+  bmp_forward(f, bmpinfo.FileSize);
+
+  free(coltable);
+  *gmp = gm;
+  return 0;
+
+ eof:
+  free(coltable);
+  *gmp = gm;
+  return 1;
+
+ format_error:
+ try_error:
+  free(coltable);
+  free(gm);
+  if (!gm_read_error) {
+    gm_read_error = "invalid bmp file";
+  }
+  return -2;
+
+ std_error:
+  free(coltable);
+  free(gm);
+  return -1;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* write a pgm stream, either P2 or (if raw != 0) P5 format. Include
+   one-line comment if non-NULL. Mode determines how out-of-range
+   color values are converted. Gamma is the desired gamma correction,
+   if any (set to 2.2 if the image is to look optimal on a CRT monitor,
+   2.8 for LCD). Set to 1.0 for no gamma correction */
+
+int gm_writepgm(FILE *f, greymap_t *gm, char *comment, int raw, int mode, double gamma) {
+  int x, y, v;
+  int gammatable[256];
+  
+  /* prepare gamma correction lookup table */
+  if (gamma != 1.0) {
+    gammatable[0] = 0;
+    for (v=1; v<256; v++) {
+      gammatable[v] = (int)(255 * exp(log(v/255.0)/gamma) + 0.5);
+    }
+  } else {
+    for (v=0; v<256; v++) {
+      gammatable[v] = v;
+    }
+  }  
+
+  fprintf(f, raw ? "P5\n" : "P2\n");
+  if (comment && *comment) {
+    fprintf(f, "# %s\n", comment);
+  }
+  fprintf(f, "%d %d 255\n", gm->w, gm->h);
+  for (y=gm->h-1; y>=0; y--) {
+    for (x=0; x<gm->w; x++) {
+      v = GM_UGET(gm, x, y);
+      if (mode == GM_MODE_NONZERO) {
+	if (v > 255) {
+	  v = 510 - v;
+	}
+	if (v < 0) {
+	  v = 0;
+	}
+      } else if (mode == GM_MODE_ODD) {
+	v = mod(v, 510);
+	if (v > 255) {
+	  v = 510 - v;
+	}
+      } else if (mode == GM_MODE_POSITIVE) {
+	if (v < 0) {
+	  v = 0;
+	} else if (v > 255) {
+	  v = 255;
+	}
+      } else if (mode == GM_MODE_NEGATIVE) {
+	v = 510 - v;
+	if (v < 0) {
+	  v = 0;
+	} else if (v > 255) {
+	  v = 255;
+	}
+      }
+      v = gammatable[v];
+      
+      if (raw) {
+	fputc(v, f);
+      } else {
+	fprintf(f, x == gm->w-1 ? "%d\n" : "%d ", v);
+      }	  
+    }
+  }
+  return 0;
+}
+
+/* ---------------------------------------------------------------------- */
+/* output - for primitive debugging purposes only! */
+
+/* print greymap to screen */
+int gm_print(FILE *f, greymap_t *gm) {
+  int x, y;
+  int xx, yy;
+  int d, t;
+  int sw, sh;
+
+  sw = gm->w < 79 ? gm->w : 79;
+  sh = gm->w < 79 ? gm->h : gm->h*sw*44/(79*gm->w);
+
+  for (yy=sh-1; yy>=0; yy--) {
+    for (xx=0; xx<sw; xx++) {
+      d=0;
+      t=0;
+      for (x=xx*gm->w/sw; x<(xx+1)*gm->w/sw; x++) {
+	for (y=yy*gm->h/sh; y<(yy+1)*gm->h/sh; y++) {
+	  d += GM_GET(gm, x, y);
+	  t += 256;
+	}
+      }
+      fputc("*#=- "[5*d/t], f);  /* what a cute trick :) */
+    }
+    fputc('\n', f);
+  }
+  return 0;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/greymap.h b/Build/source/libs/potrace/potrace-src/src/greymap.h
new file mode 100644
index 00000000000..7a5011ab8f8
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/greymap.h
@@ -0,0 +1,59 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef GREYMAP_H
+#define GREYMAP_H
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+
+/* internal format for greymaps. Note: in this format, rows are
+   ordered from bottom to top. The pixels in each row are given from
+   left to right. */
+
+struct greymap_s {
+  int w;                 /* width, in pixels */
+  int h;                 /* height, in pixels */
+  signed short int *map;    /* raw data, w*h values */
+};
+typedef struct greymap_s greymap_t;
+
+/* macros for accessing pixel at index (x,y). Note that the origin is
+   in the *lower* left corner. U* macros omit the bounds check. */
+
+#define gm_index(gm, x, y) (&(gm)->map[(x)+(y)*(ptrdiff_t)(gm)->w])
+#define gm_safe(gm, x, y) ((int)(x)>=0 && (int)(x)<(gm)->w && (int)(y)>=0 && (int)(y)<(gm)->h)
+#define gm_bound(x, m) ((x)<0 ? 0 : (x)>=(m) ? (m)-1 : (x))
+#define GM_UGET(gm, x, y) (*gm_index(gm, x, y))
+#define GM_UINC(gm, x, y, b) (*gm_index(gm, x, y) += (short int)(b))
+#define GM_UINV(gm, x, y) (*gm_index(gm, x, y) = 255 - *gm_index(gm, x, y))
+#define GM_UPUT(gm, x, y, b) (*gm_index(gm, x, y) = (short int)(b))
+#define GM_GET(gm, x, y) (gm_safe(gm, x, y) ? GM_UGET(gm, x, y) : 0)
+#define GM_INC(gm, x, y, b) (gm_safe(gm, x, y) ? GM_UINC(gm, x, y, b) : 0)
+#define GM_INV(gm, x, y) (gm_safe(gm, x, y) ? GM_UINV(gm, x, y) : 0)
+#define GM_PUT(gm, x, y, b) (gm_safe(gm, x, y) ? GM_UPUT(gm, x, y, b) : 0)
+#define GM_BGET(gm, x, y) GM_UGET(gm, gm_bound(x, gm->w), gm_bound(y, gm->h))
+
+/* modes for cutting off out-of-range values. The following names
+   refer to winding numbers. I.e., make a pixel black if winding
+   number is nonzero, odd, or positive, respectively. We assume that 0
+   winding number corresponds to white (255). */
+#define GM_MODE_NONZERO 1
+#define GM_MODE_ODD 2
+#define GM_MODE_POSITIVE 3
+#define GM_MODE_NEGATIVE 4
+
+extern char *gm_read_error;
+
+greymap_t *gm_new(int w, int h);
+greymap_t *gm_dup(greymap_t *gm);
+void gm_free(greymap_t *gm);
+void gm_clear(greymap_t *gm, int b);
+int gm_read(FILE *f, greymap_t **gmp);
+int gm_writepgm(FILE *f, greymap_t *gm, char *comment, int raw, int mode, double gamma);
+int gm_print(FILE *f, greymap_t *gm);
+
+#endif /* GREYMAP_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/libpotrace-export.sym b/Build/source/libs/potrace/potrace-src/src/libpotrace-export.sym
new file mode 100644
index 00000000000..74d55c87482
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/libpotrace-export.sym
@@ -0,0 +1,5 @@
+potrace_state_free
+potrace_param_default
+potrace_trace
+potrace_param_free
+potrace_version
diff --git a/Build/source/libs/potrace/potrace-src/src/lists.h b/Build/source/libs/potrace/potrace-src/src/lists.h
new file mode 100644
index 00000000000..394262c23ee
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/lists.h
@@ -0,0 +1,285 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef _PS_LISTS_H
+#define _PS_LISTS_H
+
+/* here we define some general list macros. Because they are macros,
+   they should work on any datatype with a "->next" component. Some of
+   them use a "hook". If elt and list are of type t* then hook is of
+   type t**. A hook stands for an insertion point in the list, i.e.,
+   either before the first element, or between two elements, or after
+   the last element. If an operation "sets the hook" for an element,
+   then the hook is set to just before the element. One can insert
+   something at a hook. One can also unlink at a hook: this means,
+   unlink the element just after the hook. By "to unlink", we mean the
+   element is removed from the list, but not deleted. Thus, it and its
+   components still need to be freed. */
+
+/* Note: these macros are somewhat experimental. Only the ones that
+   are actually *used* have been tested. So be careful to test any
+   that you use. Looking at the output of the preprocessor, "gcc -E"
+   (possibly piped though "indent"), might help too. Also: these
+   macros define some internal (local) variables that start with
+   "_". */
+
+/* we enclose macro definitions whose body consists of more than one
+   statement in MACRO_BEGIN and MACRO_END, rather than '{' and '}'.  The
+   reason is that we want to be able to use the macro in a context
+   such as "if (...) macro(...); else ...". If we didn't use this obscure
+   trick, we'd have to omit the ";" in such cases. */
+
+#define MACRO_BEGIN do {
+#define MACRO_END   } while (0)
+
+/* ---------------------------------------------------------------------- */
+/* macros for singly-linked lists */
+
+/* traverse list. At the end, elt is set to NULL. */
+#define list_forall(elt, list)   for (elt=list; elt!=NULL; elt=elt->next)
+
+/* set elt to the first element of list satisfying boolean condition
+   c, or NULL if not found */
+#define list_find(elt, list, c) \
+  MACRO_BEGIN list_forall(elt, list) if (c) break; MACRO_END
+
+/* like forall, except also set hook for elt. */
+#define list_forall2(elt, list, hook) \
+  for (elt=list, hook=&list; elt!=NULL; hook=&elt->next, elt=elt->next)
+
+/* same as list_find, except also set hook for elt. */
+#define list_find2(elt, list, c, hook) \
+  MACRO_BEGIN list_forall2(elt, list, hook) if (c) break; MACRO_END
+
+/* same, except only use hook. */
+#define _list_forall_hook(list, hook) \
+  for (hook=&list; *hook!=NULL; hook=&(*hook)->next)
+
+/* same, except only use hook. Note: c may only refer to *hook, not elt. */
+#define _list_find_hook(list, c, hook) \
+  MACRO_BEGIN _list_forall_hook(list, hook) if (c) break; MACRO_END
+
+/* insert element after hook */
+#define list_insert_athook(elt, hook) \
+  MACRO_BEGIN elt->next = *hook; *hook = elt; MACRO_END
+
+/* insert element before hook */
+#define list_insert_beforehook(elt, hook) \
+  MACRO_BEGIN elt->next = *hook; *hook = elt; hook=&elt->next; MACRO_END
+
+/* unlink element after hook, let elt be unlinked element, or NULL.
+   hook remains. */
+#define list_unlink_athook(list, elt, hook) \
+  MACRO_BEGIN \
+  elt = hook ? *hook : NULL; if (elt) { *hook = elt->next; elt->next = NULL; }\
+  MACRO_END
+
+/* unlink the specific element, if it is in the list. Otherwise, set
+   elt to NULL */
+#define list_unlink(listtype, list, elt)      \
+  MACRO_BEGIN  	       	       	       	      \
+  listtype **_hook;			      \
+  _list_find_hook(list, *_hook==elt, _hook);  \
+  list_unlink_athook(list, elt, _hook);	      \
+  MACRO_END
+
+/* prepend elt to list */
+#define list_prepend(list, elt) \
+  MACRO_BEGIN elt->next = list; list = elt; MACRO_END
+
+/* append elt to list. */
+#define list_append(listtype, list, elt)     \
+  MACRO_BEGIN                                \
+  listtype **_hook;                          \
+  _list_forall_hook(list, _hook) {}          \
+  list_insert_athook(elt, _hook);            \
+  MACRO_END
+
+/* unlink the first element that satisfies the condition. */
+#define list_unlink_cond(listtype, list, elt, c)     \
+  MACRO_BEGIN                                        \
+  listtype **_hook;			  	     \
+  list_find2(elt, list, c, _hook);                   \
+  list_unlink_athook(list, elt, _hook);              \
+  MACRO_END
+
+/* let elt be the nth element of the list, starting to count from 0.
+   Return NULL if out of bounds.   */
+#define list_nth(elt, list, n)                                \
+  MACRO_BEGIN                                                 \
+  int _x;  /* only evaluate n once */                         \
+  for (_x=(n), elt=list; _x && elt; _x--, elt=elt->next) {}   \
+  MACRO_END
+
+/* let elt be the nth element of the list, starting to count from 0.
+   Return NULL if out of bounds.   */
+#define list_nth_hook(elt, list, n, hook)                     \
+  MACRO_BEGIN                                                 \
+  int _x;  /* only evaluate n once */                         \
+  for (_x=(n), elt=list, hook=&list; _x && elt; _x--, hook=&elt->next, elt=elt->next) {}   \
+  MACRO_END
+
+/* set n to the length of the list */
+#define list_length(listtype, list, n)                   \
+  MACRO_BEGIN          	       	       	       	       	 \
+  listtype *_elt;   			 		 \
+  n=0;					 		 \
+  list_forall(_elt, list) 		 		 \
+    n++;				 		 \
+  MACRO_END
+
+/* set n to the index of the first element satisfying cond, or -1 if
+   none found. Also set elt to the element, or NULL if none found. */
+#define list_index(list, n, elt, c)                      \
+  MACRO_BEGIN				 		 \
+  n=0;					 		 \
+  list_forall(elt, list) {		 		 \
+    if (c) break;			 		 \
+    n++;				 		 \
+  }					 		 \
+  if (!elt)				 		 \
+    n=-1;				 		 \
+  MACRO_END
+
+/* set n to the number of elements in the list that satisfy condition c */
+#define list_count(list, n, elt, c)                      \
+  MACRO_BEGIN				 		 \
+  n=0;					 		 \
+  list_forall(elt, list) {		 		 \
+    if (c) n++;				 		 \
+  }                                                      \
+  MACRO_END
+
+/* let elt be each element of the list, unlinked. At the end, set list=NULL. */
+#define list_forall_unlink(elt, list) \
+  for (elt=list; elt ? (list=elt->next, elt->next=NULL), 1 : 0; elt=list)
+
+/* reverse a list (efficient) */
+#define list_reverse(listtype, list)            \
+  MACRO_BEGIN				 	\
+  listtype *_list1=NULL, *elt;			\
+  list_forall_unlink(elt, list) 		\
+    list_prepend(_list1, elt);			\
+  list = _list1;				\
+  MACRO_END
+
+/* insert the element ELT just before the first element TMP of the
+   list for which COND holds. Here COND must be a condition of ELT and
+   TMP.  Typical usage is to insert an element into an ordered list:
+   for instance, list_insert_ordered(listtype, list, elt, tmp,
+   elt->size <= tmp->size).  Note: if we give a "less than or equal"
+   condition, the new element will be inserted just before a sequence
+   of equal elements. If we give a "less than" condition, the new
+   element will be inserted just after a list of equal elements.
+   Note: it is much more efficient to construct a list with
+   list_prepend and then order it with list_merge_sort, than to
+   construct it with list_insert_ordered. */
+#define list_insert_ordered(listtype, list, elt, tmp, cond) \
+  MACRO_BEGIN                                               \
+  listtype **_hook;                                         \
+  _list_find_hook(list, (tmp=*_hook, (cond)), _hook);       \
+  list_insert_athook(elt, _hook);                           \
+  MACRO_END
+
+/* sort the given list, according to the comparison condition.
+   Typical usage is list_sort(listtype, list, a, b, a->size <
+   b->size).  Note: if we give "less than or equal" condition, each
+   segment of equal elements will be reversed in order. If we give a
+   "less than" condition, each segment of equal elements will retain
+   the original order. The latter is slower but sometimes
+   prettier. Average running time: n*n/2. */
+#define list_sort(listtype, list, a, b, cond)            \
+  MACRO_BEGIN                                            \
+  listtype *_newlist=NULL;                               \
+  list_forall_unlink(a, list)                            \
+    list_insert_ordered(listtype, _newlist, a, b, cond); \
+  list = _newlist;                                       \
+  MACRO_END
+
+/* a much faster sort algorithm (merge sort, n log n worst case). It
+   is required that the list type has an additional, unused next1
+   component. Note there is no curious reversal of order of equal
+   elements as for list_sort. */
+
+#define list_mergesort(listtype, list, a, b, cond)              \
+  MACRO_BEGIN						        \
+  listtype *_elt, **_hook1;				    	\
+							    	\
+  for (_elt=list; _elt; _elt=_elt->next1) {			\
+    _elt->next1 = _elt->next;				    	\
+    _elt->next = NULL;					    	\
+  }							    	\
+  do {			                               	    	\
+    _hook1 = &(list);				    	    	\
+    while ((a = *_hook1) != NULL && (b = a->next1) != NULL ) {  \
+      _elt = b->next1;					    	\
+      _list_merge_cond(listtype, a, b, cond, *_hook1);      	\
+      _hook1 = &((*_hook1)->next1);			    	\
+      *_hook1 = _elt;				            	\
+    }							    	\
+  } while (_hook1 != &(list));                                 	\
+  MACRO_END
+
+/* merge two sorted lists. Store result at &result */
+#define _list_merge_cond(listtype, a, b, cond, result)   \
+  MACRO_BEGIN                                            \
+  listtype **_hook;					 \
+  _hook = &(result);					 \
+  while (1) {                                            \
+     if (a==NULL) {					 \
+       *_hook = b;					 \
+       break;						 \
+     } else if (b==NULL) {				 \
+       *_hook = a;					 \
+       break;						 \
+     } else if (cond) {					 \
+       *_hook = a;					 \
+       _hook = &(a->next);				 \
+       a = a->next;					 \
+     } else {						 \
+       *_hook = b;					 \
+       _hook = &(b->next);				 \
+       b = b->next;					 \
+     }							 \
+  }							 \
+  MACRO_END
+
+/* ---------------------------------------------------------------------- */
+/* macros for doubly-linked lists */
+
+#define dlist_append(head, end, elt)                    \
+  MACRO_BEGIN  	       	       	       	       	       	 \
+  elt->prev = end;					 \
+  elt->next = NULL;					 \
+  if (end) {						 \
+    end->next = elt;					 \
+  } else {  						 \
+    head = elt;						 \
+  }	    						 \
+  end = elt;						 \
+  MACRO_END
+
+/* let elt be each element of the list, unlinked. At the end, set list=NULL. */
+#define dlist_forall_unlink(elt, head, end) \
+  for (elt=head; elt ? (head=elt->next, elt->next=NULL, elt->prev=NULL), 1 : (end=NULL, 0); elt=head)
+
+/* unlink the first element of the list */
+#define dlist_unlink_first(head, end, elt)               \
+  MACRO_BEGIN				       	       	 \
+  elt = head;						 \
+  if (head) {						 \
+    head = head->next;					 \
+    if (head) {						 \
+      head->prev = NULL;				 \
+    } else {						 \
+      end = NULL;					 \
+    }    						 \
+    elt->prev = NULL;					 \
+    elt->next = NULL;					 \
+  }							 \
+  MACRO_END
+
+#endif /* _PS_LISTS_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/lzw.c b/Build/source/libs/potrace/potrace-src/src/lzw.c
new file mode 100644
index 00000000000..5281bba274b
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/lzw.c
@@ -0,0 +1,415 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+/* code for adaptive LZW compression, as used in PostScript. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+
+#include "lists.h"
+#include "bitops.h"
+#include "lzw.h"
+
+/* ---------------------------------------------------------------------- */
+/* compression state specification */
+
+/* The compression algorithm follows the following specification,
+   expressed as a state machine. A state is a triple {s,d,n}, where s
+   is a string of input symbols, d is a dictionary, which is a
+   function from strings to output symbols, and n is the dictionary
+   size, or equivalently, the next unused output symbol. There are
+   also special states init and stop. emit[b, code] is a function
+   which emits the code 'code' as a b-bit value into the output
+   bitstream. hibit(n) returns the least number of binary digits
+   required to represent n.
+
+   init ---> {[], newdict, 258}
+
+     where [] is the empty string, and newdict maps each of the 256
+     singleton strings to itself. (Note that there are two special
+     output symbols 256 and 257, so that the next available one is
+     258). Note: hibit(258)=9.
+
+   {[], d, n} (input c) ---> (emit[hibit(n), 256]) {c, d, n}
+
+   {s,d,n} (input c) ---> {s*c,d,n}
+
+     if s!=[], s*c is in the domain of d. Here s*c is the strings s
+     extended by the character c.
+
+   {s,d,n} (input c) ---> (emit[hibit(n), d(s)]) {c,d',n+1}
+
+     if s!=[], s*c is not in the domain of d, and hibit(n+2) <= 12.
+     Here d'=d+{s*c->n}.
+
+   {s,d,n} (input c) ---> 
+           (emit[hibit(n), d(s)]) (emit[hibit(n+1), 256]) {c, newdict, 258}
+
+     if s!=[], s*c is not in the domain of d, and hibit(n+2) > 12.
+
+   {s,d,n} (input EOD) ---> (emit[hibit(n), d(s)]) (emit[hibit(n+1), 257]) stop
+
+     where s != []. Here, EOD stands for end-of-data.
+
+   {[],d,n} (input EOD) ---> (emit[hibit(n), 256]) (emit[hibit(n), 257]) stop
+
+   Notes: 
+
+   * Each reachable state {s,d,n} satisfies hibit(n+1) <= 12.
+   * Only codes of 12 or fewer bits are emitted.
+   * Each reachable state {s,d,n} satisfies s=[] or s is in the domain of d.
+   * The domain of d is always prefix closed (except for the empty prefix)
+   * The state machine is deterministic and non-blocking.
+
+*/
+   
+
+/* ---------------------------------------------------------------------- */
+/* private state */
+
+#define BITBUF_TYPE unsigned int
+
+/* the dictionary is implemented as a tree of strings under the prefix
+   order. The tree is in turns represented as a linked list of
+   lzw_dict_t structures, with "children" pointing to a node's first
+   child, and "next" pointing to a node's next sibling. As an
+   optimization, the top-level nodes (singleton strings) are
+   implemented lazily, i.e., the corresponding entry is not actually
+   created until it is accessed. */
+
+struct lzw_dict_s {
+  char c;      /* last character of string represented by this entry */
+  int code;    /* code for the string represented by this entry */
+  int freq;    /* how often searched? For optimization only */
+  struct lzw_dict_s *children;  /* list of sub-entries */
+  struct lzw_dict_s *next;      /* for making a linked list */
+};
+typedef struct lzw_dict_s lzw_dict_t;
+
+/* A state {s,d,n} is represented by the "dictionary state" part of
+   the lzw_state_t structure. Here, s is a pointer directly to the node
+   of the dictionary structure corresponding to the string s, or NULL
+   if s=[]. Further, the lzw_state_t structure contains a buffer of
+   pending output bits, and a flag indicating whether the EOD (end of
+   data) has been reached in the input. */
+
+struct lzw_state_s {
+  /* dictionary state */
+  int n;           /* current size of the dictionary */
+  lzw_dict_t *d;     /* pointer to dictionary */
+  lzw_dict_t *s;     /* pointer to current string, or NULL at beginning */
+
+  /* buffers for pending output */
+  BITBUF_TYPE buf; /* bits scheduled for output - left aligned, 0 padded */
+  int bufsize;     /* number of bits scheduled for output. */
+  int eod;         /* flush buffer? */
+};
+typedef struct lzw_state_s lzw_state_t;
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions which operate on dictionary states */
+
+/* recursively free an lzw_dict_t object */
+static void lzw_free_dict(lzw_dict_t *s) {
+  lzw_dict_t *e;
+
+  list_forall_unlink(e, s) {
+    lzw_free_dict(e->children);
+    free(e);
+  }
+}
+
+/* re-initialize the lzw state's dictionary state to "newdict",
+   freeing any old dictionary. */
+static void lzw_clear_table(lzw_state_t *st) {
+
+  lzw_free_dict(st->d);
+  st->d = NULL;
+  st->n = 258;
+  st->s = NULL;
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions for reading/writing the bit buffer */
+
+/* write the code to the bit buffer. Precondition st->bufsize <= 7.
+   Note: this does not change the dictionary state; in particular,
+   n must be updated between consecutive calls. */
+static inline void lzw_emit(int code, lzw_state_t *st) {
+  BITBUF_TYPE mask;
+  int bits = hibit(st->n);
+
+  /* fill bit buffer */
+  mask = (1 << bits) - 1;
+  code &= mask;
+
+  st->buf |= code << (8*sizeof(BITBUF_TYPE) - st->bufsize - bits);
+  st->bufsize += bits;
+}
+
+/* transfer one byte from bit buffer to output. Precondition:
+   s->avail_out > 0. */
+static inline void lzw_read_bitbuf(lzw_stream_t *s) {
+  int ch;
+  lzw_state_t *st = (lzw_state_t *)s->internal;
+
+  ch = st->buf >> (8*sizeof(BITBUF_TYPE)-8);
+  st->buf <<= 8;
+  st->bufsize -= 8;
+
+  s->next_out[0] = ch;
+  s->next_out++;
+  s->avail_out--;
+}
+
+/* ---------------------------------------------------------------------- */
+/* The following functions implement the state machine. */
+
+/* perform state transition of the state st on input character
+   ch. This updates the dictionary state and/or writes to the bit
+   buffer. Precondition: st->bufsize <= 7. Return 0 on success, or 1
+   on error with errno set. */
+static int lzw_encode_char(lzw_state_t *st, char c) {
+  lzw_dict_t *e;
+
+  /* st = {s,d,n}. hibit(n+1)<=12. */
+
+  /* {[], d, n} (input c) ---> (emit[hibit(n), 256]) {c, d, n} */
+  if (st->s == NULL) {
+    lzw_emit(256, st);
+    goto singleton;  /* enter singleton state c */
+  } 
+
+  /* {s,d,n} (input c) ---> {s*c,d,n} */
+  list_find(e, st->s->children, e->c == c);
+  if (e) {
+    e->freq++;
+    st->s = e;
+    return 0;
+  }
+
+  /* {s,d,n} (input c) ---> (emit[hibit(n), d(s)]) {c,d',n+1} */
+  /* {s,d,n} (input c) --->
+	    (emit[hibit(n), d(s)]) (emit[hibit(n+1), 256]) {c, newdict, 258} */
+
+  lzw_emit(st->s->code, st); /* 9-12 bits */
+  if (st->n >= 4094) {   /* hibit(n+2) > 12 */
+    st->n++;
+    lzw_emit(256, st);
+    goto dictfull;    /* reset dictionary and enter singleton state c */
+  }
+
+  /* insert new code in dictionary, if possible */
+  e = (lzw_dict_t *)malloc(sizeof(lzw_dict_t));
+  if (!e) {
+    return 1;
+  }
+  e->c = c;
+  e->code = st->n;
+  e->freq = 1;
+  e->children = NULL;
+  list_prepend(st->s->children, e);
+  st->n++;
+  goto singleton;  /* enter singleton state c */
+
+ dictfull:    /* reset dictionary and enter singleton state c */
+  lzw_clear_table(st);
+  /* fall through */
+  
+ singleton:   /* enter singleton state c */
+  list_find(e, st->d, e->c == c);
+  if (!e) {  /* not found: lazily add it */
+    e = (lzw_dict_t *)malloc(sizeof(lzw_dict_t));
+    if (!e) {
+      return 1;
+    }
+    e->c = c;
+    e->code = (int)(unsigned char)c;
+    e->freq = 0;
+    e->children = NULL;
+    list_prepend(st->d, e);
+  }
+  e->freq++;
+  st->s = e;
+  return 0;
+}
+
+/* perform state transition of the state st on input EOD. The leaves
+   the dictionary state undefined and writes to the bit buffer.
+   Precondition: st->bufsize <= 7. This function must be called
+   exactly once, at the end of the stream. */
+static void lzw_encode_eod(lzw_state_t *st) {
+
+  /* {[],d,n} (input EOD) ---> 
+              (emit[hibit(n), 256]) (emit[hibit(n), 257]) stop */
+  if (st->s == NULL) {
+    lzw_emit(256, st);  /* 9 bits */
+    st->n=258;
+    lzw_emit(257, st);  /* 9 bits */
+    return;
+  } 
+
+  /* {s,d,n} (input EOD) ---> 
+             (emit[hibit(n), code]) (emit[hibit(n+1), 257]) stop */
+
+  lzw_emit(st->s->code, st); /* 9-12 bits */
+  st->n++;
+  lzw_emit(257, st);  /* 9-12 bits */
+  return;
+}
+
+/* ---------------------------------------------------------------------- */
+/* User visible functions. These implement a buffer interface. See
+   lzw.h for the API description. */
+
+lzw_stream_t *lzw_init(void) {
+  lzw_stream_t *s = NULL;
+  lzw_state_t *st = NULL;
+
+  s = (lzw_stream_t *)malloc(sizeof(lzw_stream_t));
+  if (s==NULL) {
+    goto fail;
+  }
+  st = (lzw_state_t *)malloc(sizeof(lzw_state_t));
+  if (st==NULL) {
+    goto fail;
+  }
+  st->buf = 0;
+  st->bufsize = 0;
+  st->eod = 0;
+  st->d = NULL;
+  lzw_clear_table(st);
+  s->internal = (void *) st;
+  return s;
+
+ fail:
+  free(s);
+  free(st);
+  return NULL;
+}
+
+int lzw_compress(lzw_stream_t *s, int mode) {
+  int r;
+  lzw_state_t *st = (lzw_state_t *)s->internal;
+
+  while (st->eod == 0) {
+    /* empty bit buffer */
+    while (st->bufsize > 7) {
+      if (s->avail_out == 0) {
+	return 0;
+      } else {
+	lzw_read_bitbuf(s);
+      }
+    }
+    /* fill bit buffer */
+    if (s->avail_in == 0) {
+      break;
+    } else {
+      r = lzw_encode_char(st, s->next_in[0]);
+      if (r) {
+	if (r==2) {
+	  errno = EINVAL;
+	}
+	return 1;
+      }
+      s->next_in++;
+      s->avail_in--;
+    }
+  }
+
+  if (mode==LZW_EOD && st->eod == 0) {
+    st->eod = 1;
+    lzw_encode_eod(st);
+  }
+
+  /* flush bit buffer */
+  if (st->eod) {
+    while (st->bufsize > 0) {
+      if (s->avail_out == 0) {
+	return 0;
+      } else {
+	lzw_read_bitbuf(s);
+      }
+    }
+  }
+
+  return 0;
+}
+
+void lzw_free(lzw_stream_t *s) {
+  lzw_state_t *st = (lzw_state_t *)s->internal;
+
+  lzw_free_dict(st->d);
+  free(st);
+  free(s);
+}
+
+/* ---------------------------------------------------------------------- */
+/* main function for testing and illustration purposes */
+
+#ifdef LZW_MAIN
+
+int main() {
+  lzw_stream_t *s;
+  int ch;
+  char inbuf[100];
+  char outbuf[100];
+  int i, r;
+  int mode;
+
+  s = lzw_init();
+  if (!s) {
+    goto error;
+  }
+  mode = LZW_NORMAL;
+
+  while (1) {
+    /* fill inbuf */
+    for (i=0; i<100; i++) {
+      ch = fgetc(stdin);
+      if (ch==EOF) {
+	break;
+      }
+      inbuf[i] = ch;
+    }
+    if (i<100) {   /* end of input */
+      mode = LZW_EOD;
+    }
+
+    /* compress */
+    s->next_in = inbuf;
+    s->avail_in = i;
+    do {
+      s->next_out = outbuf;
+      s->avail_out = 100;
+      r = lzw_compress(s, mode);
+      if (r) {
+	goto error;
+      }
+      fwrite(outbuf, 1, 100-s->avail_out, stdout);
+    } while (s->avail_out==0);
+    if (mode == LZW_EOD) {
+      break;
+    }
+  }
+  fflush(stdout);
+  lzw_free(s);
+
+  return 0;
+
+ error:
+  fprintf(stderr, "lzw: %s\n", strerror(errno));
+  lzw_free(s);
+  return 1;
+
+}
+#endif
+
diff --git a/Build/source/libs/potrace/potrace-src/src/lzw.h b/Build/source/libs/potrace/potrace-src/src/lzw.h
new file mode 100644
index 00000000000..8ac3ed6a109
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/lzw.h
@@ -0,0 +1,50 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#define LZW_NORMAL 0
+#define LZW_EOD 1
+
+/* user visible state */
+
+struct lzw_stream_s {
+  char *next_in;     /* pointer to next input character */
+  int avail_in;      /* number of input chars available */
+  char *next_out;    /* pointer to next free byte in output buffer */
+  int avail_out;     /* remaining size of output buffer */
+
+  void *internal;    /* internal state, not user accessible */
+};
+typedef struct lzw_stream_s lzw_stream_t;
+
+/* user visible functions */
+
+/* The interface for compression and decompression is the same.  The
+   application must first call lzw_init to create and initialize a
+   compression object.  Then it calls lzw_compress on this object
+   repeatedly, as follows: next_in and next_out must point to valid,
+   non-overlapping regions of memory of size at least avail_in and
+   avail_out, respectively.  The lzw_compress function will read and
+   process as many input bytes as possible as long as there is room in
+   the output buffer. It will update next_in, avail_in, next_out, and
+   avail_out accordingly. Some input may be consumed without producing
+   any output, or some output may be produced without consuming any
+   input. However, the lzw_compress function makes progress in the
+   sense that, after calling this function, at least one of avail_in
+   or avail_out is guaranteed to be 0. The mode flag is normally set
+   to LZW_NORMAL. It can be set to LZW_EOD (end of data) to indicate
+   that the current input buffer represents the entire remaining input
+   data stream.  When called with mode=LZW_EOD, and avail_out is
+   non-zero after the call, then the application may conclude that the
+   end of output has been reached. (However, if avail_out==0 after the
+   call, then lzw_compress should be called again with the remaining
+   input, if any). Finally, lzw_free should be called to deallocate
+   the lzw_stream. Lzw_init returns NULL on error, with errno
+   set. Lzw_compress returns 0 on success, and 1 on error with errno
+   set. EINVAL is used to indicate an internal error, which should not
+   happen. */
+
+lzw_stream_t *lzw_init(void);
+int lzw_compress(lzw_stream_t *s, int mode);
+void lzw_free(lzw_stream_t *s);
diff --git a/Build/source/libs/potrace/potrace-src/src/main.c b/Build/source/libs/potrace/potrace-src/src/main.c
new file mode 100644
index 00000000000..a28a25ed40d
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/main.c
@@ -0,0 +1,1268 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#define _XOPEN_SOURCE 500
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <strings.h>
+#include <getopt.h>
+#include <math.h>
+
+#include "main.h"
+#include "potracelib.h"
+#include "backend_pdf.h"
+#include "backend_eps.h"
+#include "backend_pgm.h"
+#include "backend_svg.h"
+#include "backend_xfig.h"
+#include "backend_dxf.h"
+#include "backend_geojson.h"
+#include "potracelib.h"
+#include "bitmap_io.h"
+#include "bitmap.h"
+#include "platform.h"
+#include "auxiliary.h"
+#include "progress_bar.h"
+#include "trans.h"
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+#define UNDEF ((double)(1e30))   /* a value to represent "undefined" */
+
+struct info_s info;
+
+/* ---------------------------------------------------------------------- */
+/* some data structures for option processing */
+
+struct pageformat_s {
+  char *name;
+  int w, h;
+};
+typedef struct pageformat_s pageformat_t;
+
+/* dimensions of the various page formats, in postscript points */
+static pageformat_t pageformat[] = {
+  { "a4",        595,  842 },
+  { "a3",        842, 1191 },
+  { "a5",        421,  595 },
+  { "b5",        516,  729 },
+  { "letter",    612,  792 },
+  { "legal",     612, 1008 },
+  { "tabloid",   792, 1224 },
+  { "statement", 396,  612 },
+  { "executive", 540,  720 },
+  { "folio",     612,  936 },
+  { "quarto",    610,  780 },
+  { "10x14",     720, 1008 },
+  { NULL, 0, 0 },
+};
+
+struct turnpolicy_s {
+  char *name;
+  int n;
+};
+typedef struct turnpolicy_s turnpolicy_t;
+
+/* names of turn policies */
+static turnpolicy_t turnpolicy[] = {
+  {"black",    POTRACE_TURNPOLICY_BLACK},
+  {"white",    POTRACE_TURNPOLICY_WHITE},
+  {"left",     POTRACE_TURNPOLICY_LEFT},
+  {"right",    POTRACE_TURNPOLICY_RIGHT},
+  {"minority", POTRACE_TURNPOLICY_MINORITY},
+  {"majority", POTRACE_TURNPOLICY_MAJORITY},
+  {"random",   POTRACE_TURNPOLICY_RANDOM},
+  {NULL, 0},
+};
+
+/* backends and their characteristics */
+struct backend_s {
+  char *name;       /* name of this backend */
+  char *ext;        /* file extension */
+  int fixed;        /* fixed page size backend? */
+  int pixel;        /* pixel-based backend? */
+  int multi;        /* multi-page backend? */
+  int (*init_f)(FILE *fout);                 /* initialization function */
+  int (*page_f)(FILE *fout, potrace_path_t *plist, imginfo_t *imginfo);
+                                             /* per-bitmap function */
+  int (*term_f)(FILE *fout);                 /* finalization function */
+  int opticurve;    /* opticurve capable (true Bezier curves?) */
+};
+typedef struct backend_s backend_t;  
+
+static backend_t backend[] = {
+  { "eps",        ".eps", 0, 0, 0,   NULL,     page_eps,     NULL,     1 },
+  { "postscript", ".ps",  1, 0, 1,   init_ps,  page_ps,      term_ps,  1 },
+  { "ps",         ".ps",  1, 0, 1,   init_ps,  page_ps,      term_ps,  1 },
+  { "pdf",        ".pdf", 0, 0, 1,   init_pdf, page_pdf,     term_pdf, 1 },
+  { "pdfpage",    ".pdf", 1, 0, 1,   init_pdf, page_pdfpage, term_pdf, 1 },
+  { "svg",        ".svg", 0, 0, 0,   NULL,     page_svg,     NULL,     1 },
+  { "dxf",        ".dxf", 0, 1, 0,   NULL,     page_dxf,     NULL,     1 },
+  { "geojson",    ".json",0, 1, 0,   NULL,     page_geojson, NULL,     1 },
+  { "pgm",        ".pgm", 0, 1, 1,   NULL,     page_pgm,     NULL,     1 },
+  { "gimppath",   ".svg", 0, 1, 0,   NULL,     page_gimp,    NULL,     1 },
+  { "xfig",       ".fig", 1, 0, 0,   NULL,     page_xfig,    NULL,     0 },
+  { NULL, NULL, 0, 0, 0, NULL, NULL, NULL, 0 },
+};
+
+/* look up a backend by name. If found, return 0 and set *bp. If not
+   found leave *bp unchanged and return 1, or 2 on ambiguous
+   prefix. */
+static int backend_lookup(char *name, backend_t **bp) {
+  int i;
+  int m=0;  /* prefix matches */
+  backend_t *b = NULL;
+
+  for (i=0; backend[i].name; i++) {
+    if (strcasecmp(backend[i].name, name)==0) {
+      *bp = &backend[i];
+      return 0;
+    } else if (strncasecmp(backend[i].name, name, strlen(name))==0) {
+      m++;
+      b = &backend[i];
+    }      
+  }
+  /* if there was no exact match, and exactly one prefix match, use that */
+  if (m==1) {  
+    *bp = b;
+    return 0;
+  } else if (m) {
+    return 2;
+  } else {
+    return 1;
+  }
+}
+
+/* list all available backends by name, in a comma separated list.
+   Assume the cursor starts in column j, and break lines at length
+   linelen. Do not output any trailing punctuation. Return the column
+   the cursor is in. */
+static int backend_list(FILE *fout, int j, int linelen) {
+  int i;
+
+  for (i=0; backend[i].name; i++) {
+    if (j + (int)strlen(backend[i].name) > linelen) {
+      fprintf(fout, "\n");
+      j = 0;
+    }
+    j += fprintf(fout, "%s", backend[i].name);
+    if (backend[i+1].name) {
+      j += fprintf(fout, ", ");
+    }
+  }
+  return j;
+}
+
+/* ---------------------------------------------------------------------- */
+/* some info functions */
+
+static void license(FILE *f) {
+  fprintf(f, 
+  "This program is free software; you can redistribute it and/or modify\n"
+  "it under the terms of the GNU General Public License as published by\n"
+  "the Free Software Foundation; either version 2 of the License, or\n"
+  "(at your option) any later version.\n"
+  "\n"
+  "This program is distributed in the hope that it will be useful,\n"
+  "but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
+  "MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
+  "GNU General Public License for more details.\n"
+  "\n"
+  "You should have received a copy of the GNU General Public License\n"
+  "along with this program; if not, write to the Free Software Foundation\n"
+  "Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.\n"
+	  );
+}
+
+static void show_defaults(FILE *f) {
+  fprintf(f, "Default unit: "DEFAULT_DIM_NAME"\n");
+  fprintf(f, "Default page size: "DEFAULT_PAPERFORMAT"\n");
+}
+
+static void usage(FILE *f) {
+  int j;
+
+  fprintf(f, "Usage: "POTRACE" [options] [filename...]\n");
+  fprintf(f, "General options:\n");
+  fprintf(f, " -h, --help                 - print this help message and exit\n");
+  fprintf(f, " -v, --version              - print version info and exit\n");
+  fprintf(f, " -l, --license              - print license info and exit\n");
+  fprintf(f, "File selection:\n");
+  fprintf(f, " <filename>                 - an input file\n");
+  fprintf(f, " -o, --output <filename>    - write all output to this file\n");
+  fprintf(f, " --                         - end of options; 0 or more input filenames follow\n");
+  fprintf(f, "Backend selection:\n");
+  fprintf(f, " -b, --backend <name>       - select backend by name\n");
+  fprintf(f, " -e, --eps                  - EPS backend (encapsulated PostScript) (default)\n");
+  fprintf(f, " -p, --postscript           - PostScript backend\n");
+  fprintf(f, " -s, --svg                  - SVG backend (scalable vector graphics)\n");
+  fprintf(f, " -g, --pgm                  - PGM backend (portable greymap)\n");
+  fprintf(f, " -b pdf                     - PDF backend (portable document format)\n");
+  fprintf(f, " -b pdfpage                 - fixed page-size PDF backend\n");
+  fprintf(f, " -b dxf                     - DXF backend (drawing interchange format)\n");
+  fprintf(f, " -b geojson                 - GeoJSON backend\n");
+  fprintf(f, " -b gimppath                - Gimppath backend (GNU Gimp)\n");
+  fprintf(f, " -b xfig                    - XFig backend\n");
+  fprintf(f, "Algorithm options:\n");
+  fprintf(f, " -z, --turnpolicy <policy>  - how to resolve ambiguities in path decomposition\n");
+  fprintf(f, " -t, --turdsize <n>         - suppress speckles of up to this size (default 2)\n");
+  fprintf(f, " -a, --alphamax <n>         - corner threshold parameter (default 1)\n");
+  fprintf(f, " -n, --longcurve            - turn off curve optimization\n");
+  fprintf(f, " -O, --opttolerance <n>     - curve optimization tolerance (default 0.2)\n");
+  fprintf(f, " -u, --unit <n>             - quantize output to 1/unit pixels (default 10)\n");
+  fprintf(f, " -d, --debug <n>            - produce debugging output of type n (n=1,2,3)\n");
+  fprintf(f, "Scaling and placement options:\n");
+  fprintf(f, " -P, --pagesize <format>    - page size (default is "DEFAULT_PAPERFORMAT")\n");
+  fprintf(f, " -W, --width <dim>          - width of output image\n");
+  fprintf(f, " -H, --height <dim>         - height of output image\n");
+  fprintf(f, " -r, --resolution <n>[x<n>] - resolution (in dpi) (dimension-based backends)\n");
+  fprintf(f, " -x, --scale <n>[x<n>]      - scaling factor (pixel-based backends)\n");
+  fprintf(f, " -S, --stretch <n>          - yresolution/xresolution\n");
+  fprintf(f, " -A, --rotate <angle>       - rotate counterclockwise by angle\n");
+  fprintf(f, " -M, --margin <dim>         - margin\n");
+  fprintf(f, " -L, --leftmargin <dim>     - left margin\n");
+  fprintf(f, " -R, --rightmargin <dim>    - right margin\n");
+  fprintf(f, " -T, --topmargin <dim>      - top margin\n");
+  fprintf(f, " -B, --bottommargin <dim>   - bottom margin\n");
+  fprintf(f, " --tight                    - remove whitespace around the input image\n");
+  fprintf(f, "Color options, supported by some backends:\n");
+  fprintf(f, " -C, --color #rrggbb        - set foreground color (default black)\n");
+  fprintf(f, " --fillcolor #rrggbb        - set fill color (default transparent)\n");
+  fprintf(f, " --opaque                   - make white shapes opaque\n");
+  fprintf(f, "SVG options:\n");
+  fprintf(f, " --group                    - group related paths together\n");
+  fprintf(f, " --flat                     - whole image as a single path\n");
+  fprintf(f, "Postscript/EPS/PDF options:\n");
+  fprintf(f, " -c, --cleartext            - do not compress the output\n");
+  fprintf(f, " -2, --level2               - use postscript level 2 compression (default)\n");
+#ifdef HAVE_ZLIB
+  fprintf(f, " -3, --level3               - use postscript level 3 compression\n");
+#endif
+  fprintf(f, " -q, --longcoding           - do not optimize for file size\n");
+  fprintf(f, "PGM options:\n");
+  fprintf(f, " -G, --gamma <n>            - gamma value for anti-aliasing (default 2.2)\n");
+  fprintf(f, "Frontend options:\n");
+  fprintf(f, " -k, --blacklevel <n>       - black/white cutoff in input file (default 0.5)\n");
+  fprintf(f, " -i, --invert               - invert bitmap\n");
+  fprintf(f, "Progress bar options:\n");
+  fprintf(f, " --progress                 - show progress bar\n");
+  fprintf(f, " --tty <mode>               - progress bar rendering: vt100 or dumb\n");
+  fprintf(f, "\n");
+  fprintf(f, "Dimensions can have optional units, e.g. 6.5in, 15cm, 100pt.\n");
+  fprintf(f, "Default is "DEFAULT_DIM_NAME" (or pixels for pgm, dxf, and gimppath backends).\n");
+  fprintf(f, "Possible input file formats are: pnm (pbm, pgm, ppm), bmp.\n");
+  j = fprintf(f, "Backends are: ");
+  backend_list(f, j, 78);
+  fprintf(f, ".\n");
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions for parameter parsing */
+
+/* parse a dimension of the kind "1.5in", "7cm", etc. Return result in
+   postscript points (=1/72 in). If endptr!=NULL, store pointer to
+   next character in *endptr in the manner of strtod(3). */
+static dim_t parse_dimension(char *s, char **endptr) {
+  char *p;
+  dim_t res;
+
+  res.x = strtod(s, &p);
+  res.d = 0;
+  if (p!=s) {
+    if (!strncasecmp(p, "in", 2)) {
+      res.d = DIM_IN;
+      p += 2;
+    } else if (!strncasecmp(p, "cm", 2)) {
+      res.d = DIM_CM;
+      p += 2;
+    } else if (!strncasecmp(p, "mm", 2)) {
+      res.d = DIM_MM;
+      p += 2;
+    } else if (!strncasecmp(p, "pt", 2)) {
+      res.d = DIM_PT;
+      p += 2;
+    }
+  }
+  if (endptr!=NULL) {
+    *endptr = p;
+  }
+  return res;
+}
+
+/* parse a pair of dimensions, such as "8.5x11in", "30mmx4cm" */
+static void parse_dimensions(char *s, char **endptr, dim_t *dxp, dim_t *dyp) {
+  char *p, *q;
+  dim_t dx, dy;
+
+  dx = parse_dimension(s, &p);
+  if (p==s) {
+    goto fail;
+  }
+  if (*p != 'x') {
+    goto fail;
+  }
+  p++;
+  dy = parse_dimension(p, &q);
+  if (q==p) {
+    goto fail;
+  }
+  if (dx.d && !dy.d) {
+    dy.d = dx.d;
+  } else if (!dx.d && dy.d) {
+    dx.d = dy.d;
+  }
+  *dxp = dx;
+  *dyp = dy;
+  if (endptr != NULL) {
+    *endptr = q;
+  }
+  return;
+
+ fail:
+  dx.x = dx.d = dy.x = dy.d = 0;
+  *dxp = dx;
+  *dyp = dy;
+  if (endptr != NULL) {
+    *endptr = s;
+  }
+  return;
+}
+
+static inline double double_of_dim(dim_t d, double def) {
+  if (d.d) {
+    return d.x * d.d;
+  } else {
+    return d.x * def;
+  }
+}
+
+static int parse_color(char *s) {
+  int i, d;
+  int col = 0;
+
+  if (s[0] != '#' || strlen(s) != 7) {
+    return -1;
+  }
+  for (i=0; i<6; i++) {
+    d = s[6-i];
+    if (d >= '0' && d <= '9') {
+      col |= (d-'0') << (4*i);
+    } else if (d >= 'a' && d <= 'f') {
+      col |= (d-'a'+10) << (4*i);
+    } else if (d >= 'A' && d <= 'F') {
+      col |= (d-'A'+10) << (4*i);
+    } else {
+      return -1;
+    }
+  }
+  return col;
+}  
+
+/* ---------------------------------------------------------------------- */
+/* option processing */
+
+/* codes for options that don't have short form */
+enum { 
+  OPT_TIGHT = 300,
+  OPT_FILLCOLOR,
+  OPT_OPAQUE,
+  OPT_GROUP,
+  OPT_FLAT,
+  OPT_PROGRESS,
+  OPT_TTY
+};
+
+static struct option longopts[] = {
+  {"help",          0, 0, 'h'},
+  {"version",       0, 0, 'v'},
+  {"show-defaults", 0, 0, 'V'}, /* undocumented option for compatibility */
+  {"license",       0, 0, 'l'},
+  {"width",         1, 0, 'W'},
+  {"height",        1, 0, 'H'},
+  {"resolution",    1, 0, 'r'},
+  {"scale",         1, 0, 'x'},
+  {"stretch",       1, 0, 'S'},
+  {"margin",        1, 0, 'M'},
+  {"leftmargin",    1, 0, 'L'},
+  {"rightmargin",   1, 0, 'R'},
+  {"topmargin",     1, 0, 'T'},
+  {"bottommargin",  1, 0, 'B'},
+  {"tight",         0, 0, OPT_TIGHT},
+  {"rotate",        1, 0, 'A'},
+  {"pagesize",      1, 0, 'P'},
+  {"turdsize",      1, 0, 't'},
+  {"unit",          1, 0, 'u'},
+  {"cleartext",     0, 0, 'c'},
+  {"level2",        0, 0, '2'},
+  {"level3",        0, 0, '3'},
+  {"eps",           0, 0, 'e'},
+  {"postscript",    0, 0, 'p'},
+  {"svg",           0, 0, 's'},
+  {"pgm",           0, 0, 'g'},
+  {"backend",       1, 0, 'b'},
+  {"debug",         1, 0, 'd'},
+  {"color",         1, 0, 'C'},
+  {"fillcolor",     1, 0, OPT_FILLCOLOR},
+  {"turnpolicy",    1, 0, 'z'},
+  {"gamma",         1, 0, 'G'},
+  {"longcurve",     0, 0, 'n'},
+  {"longcoding",    0, 0, 'q'},
+  {"alphamax",      1, 0, 'a'},
+  {"opttolerance",  1, 0, 'O'},
+  {"output",        1, 0, 'o'},
+  {"blacklevel",    1, 0, 'k'},
+  {"invert",        0, 0, 'i'},
+  {"opaque",        0, 0, OPT_OPAQUE},
+  {"group",         0, 0, OPT_GROUP},
+  {"flat",          0, 0, OPT_FLAT},
+  {"progress",      0, 0, OPT_PROGRESS},
+  {"tty",           1, 0, OPT_TTY},
+
+  {0, 0, 0, 0}
+};
+
+static char *shortopts = "hvVlW:H:r:x:S:M:L:R:T:B:A:P:t:u:c23epsgb:d:C:z:G:nqa:O:o:k:i";
+
+static void dopts(int ac, char *av[]) {
+  int c;
+  char *p;
+  int i, j, r;
+  dim_t dim, dimx, dimy;
+  int matches, bestmatch;
+
+  /* defaults */
+  backend_lookup("eps", &info.backend);
+  info.debug = 0;
+  info.width_d.x = UNDEF;
+  info.height_d.x = UNDEF;
+  info.rx = UNDEF;
+  info.ry = UNDEF;
+  info.sx = UNDEF;
+  info.sy = UNDEF;
+  info.stretch = 1;
+  info.lmar_d.x = UNDEF;
+  info.rmar_d.x = UNDEF;
+  info.tmar_d.x = UNDEF;
+  info.bmar_d.x = UNDEF;
+  info.angle = 0;
+  info.paperwidth = DEFAULT_PAPERWIDTH;
+  info.paperheight = DEFAULT_PAPERHEIGHT;
+  info.tight = 0;
+  info.unit = 10;
+  info.compress = 1;
+  info.pslevel = 2;
+  info.color = 0x000000;
+  info.gamma = 2.2;
+  info.param = potrace_param_default();
+  if (!info.param) {
+    fprintf(stderr, ""POTRACE": %s\n", strerror(errno));
+    exit(1);
+  }
+  info.longcoding = 0;
+  info.outfile = NULL;
+  info.blacklevel = 0.5;
+  info.invert = 0;
+  info.opaque = 0;
+  info.grouping = 1;
+  info.fillcolor = 0xffffff;
+  info.progress = 0;
+  info.progress_bar = DEFAULT_PROGRESS_BAR;
+
+  while ((c = getopt_long(ac, av, shortopts, longopts, NULL)) != -1) {
+    switch (c) {
+    case 'h':
+      fprintf(stdout, ""POTRACE" "VERSION". Transforms bitmaps into vector graphics.\n\n");
+      usage(stdout);
+      exit(0);
+      break;
+    case 'v':
+    case 'V':
+      fprintf(stdout, ""POTRACE" "VERSION". Copyright (C) 2001-2015 Peter Selinger.\n");
+      fprintf(stdout, "Library version: %s\n", potrace_version());
+      show_defaults(stdout);
+      exit(0);
+      break;
+    case 'l':
+      fprintf(stdout, ""POTRACE" "VERSION". Copyright (C) 2001-2015 Peter Selinger.\n\n");
+      license(stdout);
+      exit(0);
+      break;
+    case 'W':
+      info.width_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'H':
+      info.height_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'r':
+      parse_dimensions(optarg, &p, &dimx, &dimy);
+      if (*p == 0 && dimx.d == 0 && dimy.d == 0 && dimx.x != 0.0 && dimy.x != 0.0) {
+	info.rx = dimx.x;
+	info.ry = dimy.x;
+	break;
+      }
+      dim = parse_dimension(optarg, &p);
+      if (*p == 0 && dim.d == 0 && dim.x != 0.0) {
+	info.rx = info.ry = dim.x;
+	break;
+      }
+      fprintf(stderr, ""POTRACE": invalid resolution -- %s\n", optarg);
+      exit(1);
+      break;
+    case 'x':
+      parse_dimensions(optarg, &p, &dimx, &dimy);
+      if (*p == 0 && dimx.d == 0 && dimy.d == 0) {
+	info.sx = dimx.x;
+	info.sy = dimy.x;
+	break;
+      }
+      dim = parse_dimension(optarg, &p);
+      if (*p == 0 && dim.d == 0) {
+	info.sx = info.sy = dim.x;
+	break;
+      }
+      fprintf(stderr, ""POTRACE": invalid scaling factor -- %s\n", optarg);
+      exit(1);
+      break;
+    case 'S':
+      info.stretch = atof(optarg);
+      break;
+    case 'M':
+      info.lmar_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      info.rmar_d = info.tmar_d = info.bmar_d = info.lmar_d;
+      break;
+    case 'L':
+      info.lmar_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'R':
+      info.rmar_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'T':
+      info.tmar_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'B':
+      info.bmar_d = parse_dimension(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid dimension -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case OPT_TIGHT:
+      info.tight = 1;
+      break;
+    case 'A':
+      info.angle = strtod(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid angle -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'P':
+      matches = 0;
+      bestmatch = 0;
+      for (i=0; pageformat[i].name!=NULL; i++) {
+        if (strcasecmp(pageformat[i].name, optarg)==0) {
+          matches = 1;
+          bestmatch = i;
+          break;
+	} else if (strncasecmp(pageformat[i].name, optarg, strlen(optarg))==0) {
+	  /* don't allow partial match on "10x14" */
+	  if (optarg[0] != '1') {
+	    matches++;
+	    bestmatch = i;
+	  }
+	}
+      }
+      if (matches == 1) {
+	info.paperwidth = pageformat[bestmatch].w;
+	info.paperheight = pageformat[bestmatch].h;
+	break;
+      }
+      parse_dimensions(optarg, &p, &dimx, &dimy);
+      if (*p == 0) {
+	info.paperwidth = (int)rint(double_of_dim(dimx, DEFAULT_DIM));
+	info.paperheight = (int)rint(double_of_dim(dimy, DEFAULT_DIM));
+	break;
+      }
+      if (matches == 0) {
+	fprintf(stderr, ""POTRACE": unrecognized page format -- %s\n", optarg);
+      } else {
+	fprintf(stderr, ""POTRACE": ambiguous page format -- %s\n", optarg);
+      }
+      j = fprintf(stderr, "Use one of: ");
+      for (i=0; pageformat[i].name!=NULL; i++) {
+	if (j + strlen(pageformat[i].name) > 75) {
+	  fprintf(stderr, "\n");
+	  j = 0;
+	}
+	j += fprintf(stderr, "%s, ", pageformat[i].name);
+      }
+      fprintf(stderr, "or specify <dim>x<dim>.\n");
+      exit(1);
+      break;
+    case 't':
+      info.param->turdsize = atoi(optarg);
+      break;
+    case 'u':
+      info.unit = strtod(optarg, &p);
+      if (*p) {
+        fprintf(stderr, ""POTRACE": invalid unit -- %s\n", optarg);
+        exit(1);
+      }
+      break;
+    case 'c':
+      info.pslevel = 2;
+      info.compress = 0;
+      break;
+    case '2':
+      info.pslevel = 2;
+      info.compress = 1;
+      break;
+    case '3':
+#ifdef HAVE_ZLIB
+      info.pslevel = 3;
+      info.compress = 1;
+#else
+      fprintf(stderr, ""POTRACE": option -3 not supported, using -2 instead.\n");
+      fflush(stderr);
+      info.pslevel = 2;
+      info.compress = 1;
+#endif
+      break;
+    case 'e':
+      backend_lookup("eps", &info.backend);
+      break;
+    case 'p':
+      backend_lookup("postscript", &info.backend);
+      break;
+    case 's':
+      backend_lookup("svg", &info.backend);
+      break;
+    case 'g':
+      backend_lookup("pgm", &info.backend);
+      break;
+    case 'b':
+      r = backend_lookup(optarg, &info.backend);
+      if (r==1 || r==2) {
+	if (r==1) {
+	  fprintf(stderr, ""POTRACE": unrecognized backend -- %s\n", optarg);
+	} else {
+	  fprintf(stderr, ""POTRACE": ambiguous backend -- %s\n", optarg);
+	}
+	j = fprintf(stderr, "Use one of: ");
+	backend_list(stderr, j, 70);
+	fprintf(stderr, ".\n");
+	exit(1);
+      }
+      break;
+    case 'd':
+      info.debug = atoi(optarg);
+      break;
+    case 'C':
+      info.color = parse_color(optarg);
+      if (info.color == -1) {
+	fprintf(stderr, ""POTRACE": invalid color -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case OPT_FILLCOLOR:
+      info.fillcolor = parse_color(optarg);
+      if (info.fillcolor == -1) {
+	fprintf(stderr, ""POTRACE": invalid color -- %s\n", optarg);
+	exit(1);
+      }
+      info.opaque = 1;
+      break;
+    case 'z':
+      matches = 0;
+      bestmatch = 0;
+      for (i=0; turnpolicy[i].name!=NULL; i++) {
+        if (strcasecmp(turnpolicy[i].name, optarg)==0) {
+	  matches = 1;
+	  bestmatch = i;
+          break;
+	} else if (strncasecmp(turnpolicy[i].name, optarg, strlen(optarg))==0) {
+	  matches++;
+	  bestmatch = i;
+	}
+      }
+      if (matches == 1) {
+	info.param->turnpolicy = turnpolicy[bestmatch].n;
+	break;
+      }
+      if (matches == 0) {
+	fprintf(stderr, ""POTRACE": unrecognized turnpolicy -- %s\n", optarg);
+      } else {
+	fprintf(stderr, ""POTRACE": ambiguous turnpolicy -- %s\n", optarg);
+      }
+      j = fprintf(stderr, "Use one of: ");
+      for (i=0; turnpolicy[i].name!=NULL; i++) {
+	if (j + strlen(turnpolicy[i].name) > 75) {
+	  fprintf(stderr, "\n");
+	  j = 0;
+	}
+	j += fprintf(stderr, "%s%s", turnpolicy[i].name, turnpolicy[i+1].name ? ", " : "");
+      }
+      fprintf(stderr, ".\n");
+      exit(1);
+      break;
+    case 'G':
+      info.gamma = atof(optarg);
+      break;
+    case 'n':
+      info.param->opticurve = 0;
+      break;
+    case 'q':
+      info.longcoding = 1;
+      break;
+    case 'a':
+      info.param->alphamax = strtod(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid alphamax -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'O':
+      info.param->opttolerance = strtod(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid opttolerance -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'o':
+      free(info.outfile);
+      info.outfile = strdup(optarg);
+      if (!info.outfile) {
+	fprintf(stderr, ""POTRACE": %s\n", strerror(errno));
+        exit(2);
+      }
+      break;
+    case 'k':
+      info.blacklevel = strtod(optarg, &p);
+      if (*p) {
+	fprintf(stderr, ""POTRACE": invalid blacklevel -- %s\n", optarg);
+	exit(1);
+      }
+      break;
+    case 'i':
+      info.invert = 1;
+      break;
+    case OPT_OPAQUE:
+      info.opaque = 1;
+      break;
+    case OPT_GROUP:
+      info.grouping = 2;
+      break;
+    case OPT_FLAT:
+      info.grouping = 0;
+      break;
+    case OPT_PROGRESS:
+      info.progress = 1;
+      break;
+    case OPT_TTY:
+      if (strcmp(optarg, "dumb") == 0) {
+	info.progress_bar = progress_bar_simplified;
+      } else if (strcmp(optarg, "vt100") == 0) {
+	info.progress_bar = progress_bar_vt100;
+      } else {
+	fprintf(stderr, ""POTRACE": invalid tty mode -- %s. Try --help for more info\n", optarg);
+	exit(1);
+      }
+      break;
+    case '?':
+      fprintf(stderr, "Try --help for more info\n");
+      exit(1);
+      break;
+    default:
+      fprintf(stderr, ""POTRACE": Unimplemented option -- %c\n", c);
+      exit(1);
+    }
+  }
+  info.infiles = &av[optind];
+  info.infilecount = ac-optind;
+  info.some_infiles = info.infilecount ? 1 : 0;
+
+  /* if "--" was used, even an empty list of filenames is considered
+     "some" filenames. */
+  if (strcmp(av[optind-1], "--") == 0) {
+    info.some_infiles = 1;
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* calculations with bitmap dimensions, positioning etc */
+
+/* determine the dimensions of the output based on command line and
+   image dimensions, and optionally, based on the actual image outline. */
+static void calc_dimensions(imginfo_t *imginfo, potrace_path_t *plist) {
+  double dim_def;
+  double maxwidth, maxheight, sc;
+  int default_scaling = 0;
+
+  /* we take care of a special case: if one of the image dimensions is
+     0, we change it to 1. Such an image is empty anyway, so there
+     will be 0 paths in it. Changing the dimensions avoids division by
+     0 error in calculating scaling factors, bounding boxes and
+     such. This doesn't quite do the right thing in all cases, but it
+     is better than causing overflow errors or "nan" output in
+     backends.  Human users don't tend to process images of size 0
+     anyway; they might occur in some pipelines. */
+  if (imginfo->pixwidth == 0) {
+    imginfo->pixwidth = 1;
+  }
+  if (imginfo->pixheight == 0) {
+    imginfo->pixheight = 1;
+  }
+
+  /* set the default dimension for width, height, margins */
+  if (info.backend->pixel) {
+    dim_def = DIM_PT;
+  } else {
+    dim_def = DEFAULT_DIM;
+  }
+
+  /* apply default dimension to width, height, margins */
+  imginfo->width = info.width_d.x == UNDEF ? UNDEF : double_of_dim(info.width_d, dim_def);
+  imginfo->height = info.height_d.x == UNDEF ? UNDEF : double_of_dim(info.height_d, dim_def);
+  imginfo->lmar = info.lmar_d.x == UNDEF ? UNDEF : double_of_dim(info.lmar_d, dim_def);
+  imginfo->rmar = info.rmar_d.x == UNDEF ? UNDEF : double_of_dim(info.rmar_d, dim_def);
+  imginfo->tmar = info.tmar_d.x == UNDEF ? UNDEF : double_of_dim(info.tmar_d, dim_def);
+  imginfo->bmar = info.bmar_d.x == UNDEF ? UNDEF : double_of_dim(info.bmar_d, dim_def);
+
+  /* start with a standard rectangle */
+  trans_from_rect(&imginfo->trans, imginfo->pixwidth, imginfo->pixheight);
+
+  /* if info.tight is set, tighten the bounding box */
+  if (info.tight) {
+    trans_tighten(&imginfo->trans, plist);
+  }
+
+  /* sx/rx is just an alternate way to specify width; sy/ry is just an
+     alternate way to specify height. */
+  if (info.backend->pixel) {
+    if (imginfo->width == UNDEF && info.sx != UNDEF) {
+      imginfo->width = imginfo->trans.bb[0] * info.sx;
+    }
+    if (imginfo->height == UNDEF && info.sy != UNDEF) {
+      imginfo->height = imginfo->trans.bb[1] * info.sy;
+    }
+  } else {
+    if (imginfo->width == UNDEF && info.rx != UNDEF) {
+      imginfo->width = imginfo->trans.bb[0] / info.rx * 72;
+    }
+    if (imginfo->height == UNDEF && info.ry != UNDEF) {
+      imginfo->height = imginfo->trans.bb[1] / info.ry * 72;
+    }
+  }
+
+  /* if one of width/height is specified, use stretch to determine the
+     other */
+  if (imginfo->width == UNDEF && imginfo->height != UNDEF) {
+    imginfo->width = imginfo->height / imginfo->trans.bb[1] * imginfo->trans.bb[0] / info.stretch;
+  } else if (imginfo->width != UNDEF && imginfo->height == UNDEF) {
+    imginfo->height = imginfo->width / imginfo->trans.bb[0] * imginfo->trans.bb[1] * info.stretch;
+  }
+
+  /* if width and height are still variable, tenatively use the
+     default scaling factor of 72dpi (for dimension-based backends) or
+     1 (for pixel-based backends). For fixed-size backends, this will
+     be adjusted later to fit the page. */
+  if (imginfo->width == UNDEF && imginfo->height == UNDEF) {
+    imginfo->width = imginfo->trans.bb[0];
+    imginfo->height = imginfo->trans.bb[1] * info.stretch;
+    default_scaling = 1;
+  } 
+
+  /* apply scaling */
+  trans_scale_to_size(&imginfo->trans, imginfo->width, imginfo->height);
+
+  /* apply rotation, and tighten the bounding box again, if necessary */
+  if (info.angle != 0.0) {
+    trans_rotate(&imginfo->trans, info.angle);
+    if (info.tight) {
+      trans_tighten(&imginfo->trans, plist);
+    }
+  }
+
+  /* for fixed-size backends, if default scaling was in effect,
+     further adjust the scaling to be the "best fit" for the given
+     page size and margins. */
+  if (default_scaling && info.backend->fixed) {
+    
+    /* try to squeeze it between margins */
+    maxwidth = UNDEF;
+    maxheight = UNDEF;
+    
+    if (imginfo->lmar != UNDEF && imginfo->rmar != UNDEF) {
+      maxwidth = info.paperwidth - imginfo->lmar - imginfo->rmar;
+    } 
+    if (imginfo->bmar != UNDEF && imginfo->tmar != UNDEF) {
+      maxheight = info.paperheight - imginfo->bmar - imginfo->tmar;
+    }
+    if (maxwidth == UNDEF && maxheight == UNDEF) {
+      maxwidth = max(info.paperwidth - 144, info.paperwidth * 0.75);
+      maxheight = max(info.paperheight - 144, info.paperheight * 0.75);
+    }
+    
+    if (maxwidth == UNDEF) {
+      sc = maxheight / imginfo->trans.bb[1];
+    } else if (maxheight == UNDEF) {
+      sc = maxwidth / imginfo->trans.bb[0];
+    } else {
+      sc = min(maxwidth / imginfo->trans.bb[0], maxheight / imginfo->trans.bb[1]);
+    }
+
+    /* re-scale coordinate system */
+    imginfo->width *= sc;
+    imginfo->height *= sc;
+    trans_rescale(&imginfo->trans, sc);
+  }
+
+  /* adjust margins */
+  if (info.backend->fixed) {
+    if (imginfo->lmar == UNDEF && imginfo->rmar == UNDEF) {
+      imginfo->lmar = (info.paperwidth-imginfo->trans.bb[0])/2;
+    } else if (imginfo->lmar == UNDEF) {
+      imginfo->lmar = (info.paperwidth-imginfo->trans.bb[0]-imginfo->rmar);
+    } else if (imginfo->lmar != UNDEF && imginfo->rmar != UNDEF) {
+      imginfo->lmar += (info.paperwidth-imginfo->trans.bb[0]-imginfo->lmar-imginfo->rmar)/2;
+    }
+    if (imginfo->bmar == UNDEF && imginfo->tmar == UNDEF) {
+      imginfo->bmar = (info.paperheight-imginfo->trans.bb[1])/2;
+    } else if (imginfo->bmar == UNDEF) {
+      imginfo->bmar = (info.paperheight-imginfo->trans.bb[1]-imginfo->tmar);
+    } else if (imginfo->bmar != UNDEF && imginfo->tmar != UNDEF) {
+      imginfo->bmar += (info.paperheight-imginfo->trans.bb[1]-imginfo->bmar-imginfo->tmar)/2;
+    }
+  } else {
+    if (imginfo->lmar == UNDEF) {
+      imginfo->lmar = 0;
+    }
+    if (imginfo->rmar == UNDEF) {
+      imginfo->rmar = 0;
+    }
+    if (imginfo->bmar == UNDEF) {
+      imginfo->bmar = 0;
+    }
+    if (imginfo->tmar == UNDEF) {
+      imginfo->tmar = 0;
+    }
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions for file handling */
+
+/* open a file for reading. Return stdin if filename is NULL or "-" */ 
+static FILE *my_fopen_read(char *filename) {
+  if (filename == NULL || strcmp(filename, "-") == 0) {
+    return stdin;
+  }
+  return fopen(filename, "rb");
+}
+
+/* open a file for writing. Return stdout if filename is NULL or "-" */ 
+static FILE *my_fopen_write(char *filename) {
+  if (filename == NULL || strcmp(filename, "-") == 0) {
+    return stdout;
+  }
+  return fopen(filename, "wb");
+}
+
+/* close a file, but do nothing is filename is NULL or "-" */
+static void my_fclose(FILE *f, char *filename) {
+  if (filename == NULL || strcmp(filename, "-") == 0) {
+    return;
+  }
+  fclose(f);
+}
+
+/* make output filename from input filename. Return an allocated value. */
+static char *make_outfilename(char *infile, char *ext) {
+  char *outfile;
+  char *p;
+
+  if (strcmp(infile, "-") == 0) {
+    return strdup("-");
+  }
+
+  outfile = (char *) malloc(strlen(infile)+strlen(ext)+5);
+  if (!outfile) {
+    return NULL;
+  }
+  strcpy(outfile, infile);
+  p = strrchr(outfile, '.');
+  if (p) {
+    *p = 0;
+  }
+  strcat(outfile, ext);
+
+  /* check that input and output filenames are different */
+  if (strcmp(infile, outfile) == 0) {
+    strcpy(outfile, infile);
+    strcat(outfile, "-out");
+  }
+
+  return outfile;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Process one infile */
+
+/* Process one or more bitmaps from fin, and write the results to fout
+   using the page_f function of the appropriate backend. */
+
+static void process_file(backend_t *b, const char *infile, const char *outfile, FILE *fin, FILE *fout) { 
+  int r; 
+  potrace_bitmap_t *bm = NULL; 
+  imginfo_t imginfo;
+  int eof_flag = 0;  /* to indicate premature eof */
+  int count;         /* number of bitmaps successfully processed, this file */
+  potrace_state_t *st;
+
+  for (count=0; ; count++) {
+    /* read a bitmap */
+    r = bm_read(fin, info.blacklevel, &bm);
+    switch (r) {
+    case -1:  /* system error */
+      fprintf(stderr, ""POTRACE": %s: %s\n", infile, strerror(errno));
+      exit(2);
+    case -2:  /* corrupt file format */
+      fprintf(stderr, ""POTRACE": %s: file format error: %s\n", infile, bm_read_error);
+      exit(2);
+    case -3:  /* empty file */
+      if (count>0) {  /* end of file */
+	return;
+      }
+      fprintf(stderr, ""POTRACE": %s: empty file\n", infile);
+      exit(2);
+    case -4:  /* wrong magic */
+      if (count>0) { 
+	fprintf(stderr, ""POTRACE": %s: warning: junk at end of file\n", infile);
+	return;
+      }
+      fprintf(stderr, ""POTRACE": %s: file format not recognized\n", infile);
+      fprintf(stderr, "Possible input file formats are: pnm (pbm, pgm, ppm), bmp.\n");
+      exit(2);
+    case 1:  /* unexpected end of file */
+      fprintf(stderr, ""POTRACE": warning: %s: premature end of file\n", infile);
+      eof_flag = 1;
+      break;
+    }
+
+    /* prepare progress bar, if requested */
+    if (info.progress) {
+      r = info.progress_bar->init(&info.param->progress, infile, count);
+      if (r) {
+	fprintf(stderr, ""POTRACE": %s\n", strerror(errno));
+	exit(2);
+      }
+    } else {
+      info.param->progress.callback = NULL;
+    }
+
+    if (info.invert) {
+      bm_invert(bm);
+    }
+
+    /* process the image */
+    st = potrace_trace(info.param, bm);
+    if (!st || st->status != POTRACE_STATUS_OK) {
+      fprintf(stderr, ""POTRACE": %s: %s\n", infile, strerror(errno));
+      exit(2);
+    }
+
+    /* calculate image dimensions */
+    imginfo.pixwidth = bm->w;
+    imginfo.pixheight = bm->h;
+    bm_free(bm);
+
+    calc_dimensions(&imginfo, st->plist);
+
+    r = b->page_f(fout, st->plist, &imginfo);
+    if (r) {
+      fprintf(stderr, ""POTRACE": %s: %s\n", outfile, strerror(errno));
+      exit(2);
+    }
+
+    potrace_state_free(st);
+
+    if (info.progress) {
+      info.progress_bar->term(&info.param->progress);
+    }
+
+    if (eof_flag || !b->multi) {
+      return;
+    }
+  }
+  /* not reached */
+}
+
+/* ---------------------------------------------------------------------- */
+/* main: handle file i/o */
+
+#define TRY(x) if (x) goto try_error
+
+int main(int ac, char *av[]) {
+  backend_t *b;  /* backend info */
+  FILE *fin, *fout;
+  int i;
+  char *outfile;
+
+  /* platform-specific initializations, e.g., set file i/o to binary */
+  platform_init();
+
+  /* process options */
+  dopts(ac, av);
+
+  b = info.backend;
+  if (b==NULL) {
+    fprintf(stderr, ""POTRACE": internal error: selected backend not found\n");
+    exit(1);
+  }
+
+  /* fix some parameters */
+  /* if backend cannot handle opticurve, disable it */
+  if (b->opticurve == 0) {
+    info.param->opticurve = 0;
+  }
+
+  /* there are several ways to call us:
+     potrace                     -- stdin to stdout
+     potrace -o outfile          -- stdin to outfile
+     potrace file...             -- encode each file and generate outfile names
+     potrace -o outfile file...  -- concatenate files and write to outfile
+
+     The latter form is only allowed one file for single-page
+     backends.  For multi-page backends, each file must contain 0 or
+     more complete bitmaps.
+  */
+
+  if (!info.some_infiles) {                 /* read from stdin */
+
+    fout = my_fopen_write(info.outfile);
+    if (!fout) {
+      fprintf(stderr, ""POTRACE": %s: %s\n", info.outfile ? info.outfile : "stdout", strerror(errno));
+      exit(2); 
+    }
+    if (b->init_f) {
+      TRY(b->init_f(fout));
+    }
+    process_file(b, "stdin", info.outfile ? info.outfile : "stdout", stdin, fout);
+    if (b->term_f) {
+      TRY(b->term_f(fout));
+    }
+    my_fclose(fout, info.outfile);
+    free(info.outfile);
+    potrace_param_free(info.param);
+    return 0;
+
+  } else if (!info.outfile) {                /* infiles -> multiple outfiles */
+
+    for (i=0; i<info.infilecount; i++) {
+      outfile = make_outfilename(info.infiles[i], b->ext);
+      if (!outfile) {
+	fprintf(stderr, ""POTRACE": %s\n", strerror(errno));
+	exit(2);
+      }
+      fin = my_fopen_read(info.infiles[i]);
+      if (!fin) {
+	fprintf(stderr, ""POTRACE": %s: %s\n", info.infiles[i], strerror(errno));
+	exit(2);
+      }
+      fout = my_fopen_write(outfile);
+      if (!fout) {
+	fprintf(stderr, ""POTRACE": %s: %s\n", outfile, strerror(errno));
+	exit(2);
+      }
+      if (b->init_f) {
+	TRY(b->init_f(fout));
+      }
+      process_file(b, info.infiles[i], outfile, fin, fout);
+      if (b->term_f) {
+	TRY(b->term_f(fout));
+      }
+      my_fclose(fin, info.infiles[i]);
+      my_fclose(fout, outfile);
+      free(outfile);
+    }
+    potrace_param_free(info.param);
+    return 0; 
+
+  } else {                                   /* infiles to single outfile */
+
+    if (!b->multi && info.infilecount >= 2) {
+      fprintf(stderr, ""POTRACE": cannot use multiple input files with -o in %s mode\n", b->name);
+      exit(1);
+    }
+    if (info.infilecount == 0) {
+      fprintf(stderr, ""POTRACE": cannot use empty list of input files with -o\n");
+      exit(1);
+    }
+    
+    fout = my_fopen_write(info.outfile);
+    if (!fout) {
+      fprintf(stderr, ""POTRACE": %s: %s\n", info.outfile, strerror(errno));
+      exit(2);
+    }
+    if (b->init_f) {
+      TRY(b->init_f(fout));
+    }
+    for (i=0; i<info.infilecount; i++) {
+      fin = my_fopen_read(info.infiles[i]);
+      if (!fin) {
+	fprintf(stderr, ""POTRACE": %s: %s\n", info.infiles[i], strerror(errno));
+	exit(2);
+      }
+      process_file(b, info.infiles[i], info.outfile, fin, fout);
+      my_fclose(fin, info.infiles[i]);
+    }
+    if (b->term_f) {
+      TRY(b->term_f(fout));
+    }
+    my_fclose(fout, info.outfile);
+    free(info.outfile);
+    potrace_param_free(info.param);
+    return 0;
+
+  }
+
+  /* not reached */
+
+ try_error:
+  fprintf(stderr, ""POTRACE": %s\n", strerror(errno));
+  exit(2);
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/main.h b/Build/source/libs/potrace/potrace-src/src/main.h
new file mode 100644
index 00000000000..f052c4f2b77
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/main.h
@@ -0,0 +1,109 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef MAIN_H
+#define MAIN_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "potracelib.h"
+#include "progress_bar.h"
+#include "auxiliary.h"
+#include "trans.h"
+
+/* structure to hold a dimensioned value */
+struct dim_s {
+  double x; /* value */
+  double d; /* dimension (in pt), or 0 if not given */
+};
+typedef struct dim_s dim_t;
+
+#define DIM_IN (72)
+#define DIM_CM (72 / 2.54)
+#define DIM_MM (72 / 25.4)
+#define DIM_PT (1)
+
+/* set some configurable defaults */
+
+#ifdef USE_METRIC
+#define DEFAULT_DIM DIM_CM
+#define DEFAULT_DIM_NAME "centimeters"
+#else
+#define DEFAULT_DIM DIM_IN
+#define DEFAULT_DIM_NAME "inches"
+#endif
+
+#ifdef USE_A4
+#define DEFAULT_PAPERWIDTH 595
+#define DEFAULT_PAPERHEIGHT 842
+#define DEFAULT_PAPERFORMAT "a4"
+#else
+#define DEFAULT_PAPERWIDTH 612
+#define DEFAULT_PAPERHEIGHT 792
+#define DEFAULT_PAPERFORMAT "letter"
+#endif
+
+#ifdef DUMB_TTY
+#define DEFAULT_PROGRESS_BAR progress_bar_simplified
+#else
+#define DEFAULT_PROGRESS_BAR progress_bar_vt100
+#endif
+
+
+
+struct backend_s;
+
+/* structure to hold command line options */
+struct info_s {
+  struct backend_s *backend;  /* type of backend (eps,ps,pgm etc) */
+  potrace_param_t *param;  /* tracing parameters, see potracelib.h */
+  int debug;         /* type of output (0-2) (for BACKEND_PS/EPS only) */
+  dim_t width_d;     /* desired width of image */
+  dim_t height_d;    /* desired height of image */
+  double rx;         /* desired x resolution (in dpi) */
+  double ry;         /* desired y resolution (in dpi) */
+  double sx;         /* desired x scaling factor */
+  double sy;         /* desired y scaling factor */
+  double stretch;    /* ry/rx, if not otherwise determined */
+  dim_t lmar_d, rmar_d, tmar_d, bmar_d;   /* margins */
+  double angle;      /* rotate by this many degrees */
+  int paperwidth, paperheight;  /* paper size for ps backend (in pt) */
+  int tight;         /* should bounding box follow actual vector outline? */
+  double unit;       /* granularity of output grid */
+  int compress;      /* apply compression? */
+  int pslevel;       /* postscript level to use: affects only compression */
+  int color;         /* rgb color code 0xrrggbb: line color */
+  int fillcolor;     /* rgb color code 0xrrggbb: fill color */
+  double gamma;      /* gamma value for pgm backend */
+  int longcoding;    /* do not optimize for file size? */
+  char *outfile;     /* output filename, if given */
+  char **infiles;    /* array of input filenames */
+  int infilecount;   /* number of input filenames */
+  int some_infiles;  /* do we process a list of input filenames? */
+  double blacklevel; /* 0 to 1: black/white cutoff in input file */
+  int invert;        /* invert bitmap? */
+  int opaque;        /* paint white shapes opaquely? */
+  int grouping;      /* 0=flat; 1=connected components; 2=hierarchical */
+  int progress;      /* should we display a progress bar? */
+  progress_bar_t *progress_bar;  /* which progress bar to use */
+};
+typedef struct info_s info_t;
+
+extern info_t info;
+
+/* structure to hold per-image information, set e.g. by calc_dimensions */
+struct imginfo_s {
+  int pixwidth;        /* width of input pixmap */
+  int pixheight;       /* height of input pixmap */
+  double width;        /* desired width of image (in pt or pixels) */
+  double height;       /* desired height of image (in pt or pixels) */
+  double lmar, rmar, tmar, bmar;   /* requested margins (in pt) */
+  trans_t trans;        /* specify relative position of a tilted rectangle */
+};
+typedef struct imginfo_s imginfo_t;
+
+#endif /* MAIN_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/mkbitmap.c b/Build/source/libs/potrace/potrace-src/src/mkbitmap.c
new file mode 100644
index 00000000000..c8689326145
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/mkbitmap.c
@@ -0,0 +1,790 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* mkbitmap.c: a standalone program for converting greymaps to bitmaps
+   while optionally applying the following enhancements: highpass
+   filter (evening out background gradients), lowpass filter
+   (smoothing foreground details), interpolated scaling, inversion. */
+
+#define _XOPEN_SOURCE 500
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <math.h>
+#include <getopt.h>
+
+#include "greymap.h"
+#include "bitmap_io.h"
+#include "platform.h"
+
+#define SAFE_CALLOC(var, n, typ) \
+  if ((var = (typ *)calloc(n, sizeof(typ))) == NULL) goto calloc_error 
+
+/* structure to hold command line options */
+struct info_s {
+  char *outfile;     /* output file */
+  char **infiles;    /* input files */
+  int infilecount;   /* how many input files? */
+  int invert;        /* invert input? */
+  int highpass;      /* use highpass filter? */
+  double lambda;     /* highpass filter radius */
+  int lowpass;       /* use lowpass filter? */
+  double lambda1;    /* lowpass filter radius */
+  int scale;         /* scaling factor */
+  int linear;        /* linear scaling? */
+  int bilevel;       /* convert to bilevel? */
+  double level;      /* cutoff grey level */
+  char *outext;      /* default output file extension */
+};
+typedef struct info_s info_t;
+
+static info_t info;
+
+/* apply lowpass filter (an approximate Gaussian blur) to greymap.
+   Lambda is the standard deviation of the kernel of the filter (i.e.,
+   the approximate filter radius). */
+static void lowpass(greymap_t *gm, double lambda) {
+  double f, g;
+  double c, d;
+  double B;
+  int x, y;
+
+  /* calculate filter coefficients from given lambda */
+  B = 1+2/(lambda*lambda);
+  c = B-sqrt(B*B-1);
+  d = 1-c;
+
+  for (y=0; y<gm->h; y++) {
+    /* apply low-pass filter to row y */
+    /* left-to-right */
+    f = g = 0;
+    for (x=0; x<gm->w; x++) {
+      f = f*c + GM_UGET(gm, x, y)*d;
+      g = g*c + f*d;
+      GM_UPUT(gm, x, y, g);
+    }
+
+    /* right-to-left */
+    for (x=gm->w-1; x>=0; x--) {
+      f = f*c + GM_UGET(gm, x, y)*d;
+      g = g*c + f*d;
+      GM_UPUT(gm, x, y, g);
+    }
+
+    /* left-to-right mop-up */
+    for (x=0; x<gm->w; x++) {
+      f = f*c;
+      g = g*c + f*d;
+      if (f+g < 1/255.0) {
+	break;
+      }
+      GM_UPUT(gm, x, y, GM_UGET(gm, x, y)+g);
+    }
+  }
+
+  for (x=0; x<gm->w; x++) {
+    /* apply low-pass filter to column x */
+    /* bottom-to-top */
+    f = g = 0;
+    for (y=0; y<gm->h; y++) {
+      f = f*c + GM_UGET(gm, x, y)*d;
+      g = g*c + f*d;
+      GM_UPUT(gm, x, y, g);
+    }
+
+    /* top-to-bottom */
+    for (y=gm->h-1; y>=0; y--) {
+      f = f*c + GM_UGET(gm, x, y)*d;
+      g = g*c + f*d;
+      GM_UPUT(gm, x, y, g);
+    }
+
+    /* bottom-to-top mop-up */
+    for (y=0; y<gm->h; y++) {
+      f = f*c;
+      g = g*c + f*d;
+      if (f+g < 1/255.0) {
+	break;
+      }
+      GM_UPUT(gm, x, y, GM_UGET(gm, x, y)+g);
+    }
+  }
+}
+
+/* apply highpass filter to greymap. Return 0 on success, 1 on error
+   with errno set. */
+static int highpass(greymap_t *gm, double lambda) {
+  greymap_t *gm1;
+  double f;
+  int x, y;
+
+  /* create a copy */
+  gm1 = gm_dup(gm);
+  if (!gm1) {
+    return 1;
+  }
+
+  /* apply lowpass filter to the copy */
+  lowpass(gm1, lambda);
+
+  /* subtract copy from original */
+  for (y=0; y<gm->h; y++) {
+    for (x=0; x<gm->w; x++) {
+      f = GM_UGET(gm, x, y);
+      f -= GM_UGET(gm1, x, y);
+      f += 128;    /* normalize! */
+      GM_UPUT(gm, x, y, f);
+    }
+  }
+  gm_free(gm1);
+  return 0;
+}
+
+/* Convert greymap to bitmap by using cutoff threshold c (0=black,
+   1=white). On error, return NULL with errno set. */
+static potrace_bitmap_t *threshold(greymap_t *gm, double c) {
+  int w, h;
+  potrace_bitmap_t *bm_out = NULL;
+  double c1;
+  int x, y;
+  double p;
+
+  w = gm->w;
+  h = gm->h;
+
+  /* allocate output bitmap */
+  bm_out = bm_new(w, h);
+  if (!bm_out) {
+    return NULL;
+  }
+
+  /* thresholding */
+  c1 = c * 255;
+
+  for (y=0; y<h; y++) {
+    for (x=0; x<w; x++) {
+      p = GM_UGET(gm, x, y);
+      BM_UPUT(bm_out, x, y, p < c1);
+    }
+  }
+  return bm_out;
+}
+
+/* scale greymap by factor s, using linear interpolation. If
+   bilevel=0, return a pointer to a greymap_t. If bilevel=1, return a
+   pointer to a potrace_bitmap_t and use cutoff threshold c (0=black,
+   1=white).  On error, return NULL with errno set. */
+
+static void *interpolate_linear(greymap_t *gm, int s, int bilevel, double c) {
+  int p00, p01, p10, p11;
+  int i, j, x, y;
+  double xx, yy, av;
+  double c1 = 0;
+  int w, h;
+  double p0, p1;
+  greymap_t *gm_out = NULL;
+  potrace_bitmap_t *bm_out = NULL;
+
+  w = gm->w;
+  h = gm->h;
+
+  /* allocate output bitmap/greymap */
+  if (bilevel) {
+    bm_out = bm_new(w*s, h*s);
+    if (!bm_out) {
+      return NULL;
+    }
+    bm_clear(bm_out, 0);
+    c1 = c * 255;
+  } else {
+    gm_out = gm_new(w*s, h*s);
+    if (!gm_out) {
+      return NULL;
+    }
+  }
+
+  /* interpolate */
+  for (i=0; i<w; i++) {
+    for (j=0; j<h; j++) {
+      p00 = GM_BGET(gm, i, j);
+      p01 = GM_BGET(gm, i, j+1);
+      p10 = GM_BGET(gm, i+1, j);
+      p11 = GM_BGET(gm, i+1, j+1);
+      
+      if (bilevel) {
+	/* treat two special cases which are very common */
+	if (p00 < c1 && p01 < c1 && p10 < c1 && p11 < c1) {
+	  for (x=0; x<s; x++) {
+	    for (y=0; y<s; y++) {
+	      BM_UPUT(bm_out, i*s+x, j*s+y, 1);
+	    }
+	  }
+	  continue;
+	}
+	if (p00 >= c1 && p01 >= c1 && p10 >= c1 && p11 >= c1) {
+	  continue;
+	}
+      }
+      
+      /* the general case */
+      for (x=0; x<s; x++) {
+	xx = x/(double)s;
+	p0 = p00*(1-xx) + p10*xx;
+	p1 = p01*(1-xx) + p11*xx;
+	for (y=0; y<s; y++) {
+	  yy = y/(double)s;
+	  av = p0*(1-yy) + p1*yy;
+	  if (bilevel) {
+	    BM_UPUT(bm_out, i*s+x, j*s+y, av < c1);
+	  } else {
+	    GM_UPUT(gm_out, i*s+x, j*s+y, av);
+	  }
+	}
+      }
+    }
+  }
+  if (bilevel) {
+    return (void *)bm_out;
+  } else {
+    return (void *)gm_out;
+  }
+}
+
+/* same as interpolate_linear, except use cubic interpolation (slower
+   and better). */
+
+/* we need this typedef so that the SAFE_CALLOC macro will work */
+typedef double double4[4];
+
+static void *interpolate_cubic(greymap_t *gm, int s, int bilevel, double c) {
+  int w, h;
+  double4 *poly = NULL; /* poly[s][4]: fixed interpolation polynomials */
+  double p[4];              /* four current points */
+  double4 *window = NULL; /* window[s][4]: current state */
+  double t, v;
+  int k, l, i, j, x, y;
+  double c1 = 0;
+  greymap_t *gm_out = NULL;
+  potrace_bitmap_t *bm_out = NULL;
+
+  SAFE_CALLOC(poly, s, double4);
+  SAFE_CALLOC(window, s, double4);
+
+  w = gm->w;
+  h = gm->h;
+
+  /* allocate output bitmap/greymap */
+  if (bilevel) {
+    bm_out = bm_new(w*s, h*s);
+    if (!bm_out) {
+      goto calloc_error;
+    }
+    bm_clear(bm_out, 0);
+    c1 = c * 255;
+  } else {
+    gm_out = gm_new(w*s, h*s);
+    if (!gm_out) {
+      goto calloc_error;
+    }
+  }
+
+  /* pre-calculate interpolation polynomials */
+  for (k=0; k<s; k++) {
+    t = k/(double)s;
+    poly[k][0] = 0.5 * t * (t-1) * (1-t);
+    poly[k][1] = -(t+1) * (t-1) * (1-t) + 0.5 * (t-1) * (t-2) * t;
+    poly[k][2] = 0.5 * (t+1) * t * (1-t) - t * (t-2) * t;
+    poly[k][3] = 0.5 * t * (t-1) * t;
+  }
+
+  /* interpolate */
+  for (y=0; y<h; y++) {
+    x=0;
+    for (i=0; i<4; i++) {
+      for (j=0; j<4; j++) {
+	p[j] = GM_BGET(gm, x+i-1, y+j-1);
+      }
+      for (k=0; k<s; k++) {
+	window[k][i] = 0.0;
+	for (j=0; j<4; j++) {
+	  window[k][i] += poly[k][j] * p[j];
+	}
+      }
+    }
+    while (1) {
+      for (l=0; l<s; l++) {
+	for (k=0; k<s; k++) {
+	  v = 0.0;
+	  for (i=0; i<4; i++) {
+	    v += window[k][i] * poly[l][i];
+	  }
+	  if (bilevel) {
+	    BM_UPUT(bm_out, x*s+l, y*s+k, v < c1);
+	  } else {
+	    GM_UPUT(gm_out, x*s+l, y*s+k, v);
+	  }	    
+	}
+      }
+      x++;
+      if (x>=w) {
+	break;
+      }
+      for (i=0; i<3; i++) {
+	for (k=0; k<s; k++) {
+	  window[k][i] = window[k][i+1];
+	}
+      }
+      i=3;
+      for (j=0; j<4; j++) {
+        p[j] = GM_BGET(gm, x+i-1, y+j-1);
+      }
+      for (k=0; k<s; k++) {
+	window[k][i] = 0.0;
+        for (j=0; j<4; j++) {
+          window[k][i] += poly[k][j] * p[j];
+        }
+      }
+    }
+  }
+
+  free(poly);
+  free(window);
+
+  if (bilevel) {
+    return (void *)bm_out;
+  } else {
+    return (void *)gm_out;
+  }
+
+ calloc_error:
+  free(poly);
+  free(window);
+  return NULL;
+}
+
+/* ---------------------------------------------------------------------- */
+
+/* process a single file, containing one or more images. On error,
+   print error message to stderr and exit with code 2. On warning,
+   print warning message to stderr. */
+
+static void process_file(FILE *fin, FILE *fout, char *infile, char *outfile) {
+  int r;
+  greymap_t *gm;
+  potrace_bitmap_t *bm;
+  void *sm;
+  int x, y;
+  int count;
+
+  for (count=0; ; count++) {
+    r = gm_read(fin, &gm);
+    switch (r) {
+    case -1:  /* system error */
+      fprintf(stderr, ""MKBITMAP": %s: %s\n", infile, strerror(errno));
+      exit(2);
+    case -2:  /* corrupt file format */
+      fprintf(stderr, ""MKBITMAP": %s: file format error: %s\n", infile, gm_read_error);
+      exit(2);
+    case -3:  /* empty file */
+      if (count>0) {  /* end of file */
+	return;
+      }
+      fprintf(stderr, ""MKBITMAP": %s: empty file\n", infile);
+      exit(2);
+    case -4:  /* wrong magic */
+      if (count>0) {
+	fprintf(stderr, ""MKBITMAP": %s: warning: junk at end of file\n", infile);
+	return;
+      }
+      fprintf(stderr, ""MKBITMAP": %s: file format not recognized\n", infile);
+      fprintf(stderr, "Possible input file formats are: pnm (pbm, pgm, ppm), bmp.\n");
+      exit(2);
+    case 1:  /* unexpected end of file */
+      fprintf(stderr, ""MKBITMAP": %s: warning: premature end of file\n", infile);
+      break;
+    }
+    
+    if (info.invert) {
+      for (y=0; y<gm->h; y++) {
+	for (x=0; x<gm->w; x++) {
+	  GM_UPUT(gm, x, y, 255-GM_UGET(gm, x, y));
+	}
+      }
+    }
+    
+    if (info.highpass) {
+      r = highpass(gm, info.lambda);
+      if (r) {
+	fprintf(stderr, ""MKBITMAP": %s: %s\n", infile, strerror(errno));
+	exit(2);
+      }
+    }
+
+    if (info.lowpass) {
+      lowpass(gm, info.lambda1);
+    }
+    
+    if (info.scale == 1 && info.bilevel) {  /* no interpolation necessary */
+      sm = threshold(gm, info.level);
+      gm_free(gm);
+    } else if (info.scale == 1) {
+      sm = gm;
+    } else if (info.linear) {  /* linear interpolation */
+      sm = interpolate_linear(gm, info.scale, info.bilevel, info.level);
+      gm_free(gm);
+    } else {  /* cubic interpolation */
+      sm = interpolate_cubic(gm, info.scale, info.bilevel, info.level);
+      gm_free(gm);
+    }
+    if (!sm) {
+      fprintf(stderr, ""MKBITMAP": %s: %s\n", infile, strerror(errno));
+      exit(2);
+    }
+    
+    if (info.bilevel) {
+      bm = (potrace_bitmap_t *)sm;
+      bm_writepbm(fout, bm);
+      bm_free(bm);
+    } else {
+      gm = (greymap_t *)sm;
+      gm_writepgm(fout, gm, NULL, 1, GM_MODE_POSITIVE, 1.0);
+      gm_free(gm);
+    }
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* some info functions and option processing */
+
+static int license(FILE *f) {
+  fprintf(f, 
+  "This program is free software; you can redistribute it and/or modify\n"
+  "it under the terms of the GNU General Public License as published by\n"
+  "the Free Software Foundation; either version 2 of the License, or\n"
+  "(at your option) any later version.\n"
+  "\n"
+  "This program is distributed in the hope that it will be useful,\n"
+  "but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
+  "MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
+  "GNU General Public License for more details.\n"
+  "\n"
+  "You should have received a copy of the GNU General Public License\n"
+  "along with this program; if not, write to the Free Software Foundation\n"
+  "Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.\n"
+	  );
+  return 0;
+}
+
+static int usage(FILE *f) {
+  fprintf(f, "Usage: "MKBITMAP" [options] [file...]\n");
+  fprintf(f, "Options:\n");
+  fprintf(f, " -h, --help           - print this help message and exit\n");
+  fprintf(f, " -v, --version        - print version info and exit\n");
+  fprintf(f, " -l, --license        - print license info and exit\n");
+  fprintf(f, " -o, --output <file>  - output to file\n");
+  fprintf(f, " -x, --nodefaults     - turn off default options\n");
+  fprintf(f, "Inversion:\n");
+  fprintf(f, " -i, --invert         - invert the input (undo 'blackboard' effect)\n");
+  fprintf(f, "Highpass filtering:\n");
+  fprintf(f, " -f, --filter <n>     - apply highpass filter with radius n (default 4)\n");
+  fprintf(f, " -n, --nofilter       - no highpass filtering\n");
+  fprintf(f, " -b, --blur <n>       - apply lowpass filter with radius n (default: none)\n");
+  fprintf(f, "Scaling:\n");
+  fprintf(f, " -s, --scale <n>      - scale by integer factor n (default 2)\n");
+  fprintf(f, " -1, --linear         - use linear interpolation\n");
+  fprintf(f, " -3, --cubic          - use cubic interpolation (default)\n");
+  fprintf(f, "Thresholding:\n");
+  fprintf(f, " -t, --threshold <n>  - set threshold for bilevel conversion (default 0.45)\n");
+  fprintf(f, " -g, --grey           - no bilevel conversion, output a greymap\n");
+
+  fprintf(f, "\n");
+  fprintf(f, "Possible input file formats are: pnm (pbm, pgm, ppm), bmp.\n");
+  fprintf(f, "The default options are: -f 4 -s 2 -3 -t 0.45\n");
+  
+  return 0;
+}
+
+static struct option longopts[] = {
+  {"help",          0, 0, 'h'},
+  {"version",       0, 0, 'v'},
+  {"license",       0, 0, 'l'},
+  {"output",        1, 0, 'o'},
+  {"reset",         0, 0, 'x'},
+  {"invert",        0, 0, 'i'},
+  {"filter",        1, 0, 'f'},
+  {"nofilter",      0, 0, 'n'},
+  {"blur",          1, 0, 'b'},
+  {"scale",         1, 0, 's'},
+  {"linear",        0, 0, '1'},
+  {"cubic",         0, 0, '3'},
+  {"grey",          0, 0, 'g'},
+  {"threshold",     1, 0, 't'},
+  {0, 0, 0, 0}
+};
+
+static char *shortopts = "hvlo:xif:nb:s:13gt:";
+
+/* process options. On error, print error message to stderr and exit
+   with code 1 */
+static void dopts(int ac, char *av[]) {
+  int c;
+  char *p;
+  
+  /* set defaults for command line parameters */
+  info.outfile = NULL;    /* output file */
+  info.infiles = NULL;    /* input files */
+  info.infilecount = 0;   /* how many input files? */
+  info.invert = 0;        /* invert input? */
+  info.highpass = 1;      /* use highpass filter? */
+  info.lambda = 4;        /* highpass filter radius */
+  info.lowpass = 0;       /* use lowpass filter? */
+  info.lambda1 = 0;       /* lowpass filter radius */
+  info.scale = 2;         /* scaling factor */
+  info.linear = 0;        /* linear scaling? */
+  info.bilevel = 1;       /* convert to bilevel? */
+  info.level = 0.45;      /* cutoff grey level */
+  info.outext = ".pbm";   /* output file extension */
+
+  while ((c = getopt_long(ac, av, shortopts, longopts, NULL)) != -1) {
+    switch (c) {
+    case 'h':
+      fprintf(stdout, ""MKBITMAP" "VERSION". Transforms images into bitmaps with scaling and filtering.\n\n");
+      usage(stdout);
+      exit(0);
+      break;
+    case 'v':
+      fprintf(stdout, ""MKBITMAP" "VERSION". Copyright (C) 2001-2015 Peter Selinger.\n");
+      exit(0);
+      break;
+    case 'l':
+      fprintf(stdout, ""MKBITMAP" "VERSION". Copyright (C) 2001-2015 Peter Selinger.\n\n");
+      license(stdout);
+      exit(0);
+      break;
+    case 'o':
+      free(info.outfile);
+      info.outfile = strdup(optarg);
+      if (!info.outfile) {
+        fprintf(stderr, ""MKBITMAP": %s\n", strerror(errno));
+        exit(2);
+      }
+      break;
+    case 'x':
+      info.invert = 0;
+      info.highpass = 0;
+      info.scale = 1;
+      info.bilevel = 0;
+      info.outext = ".pgm";
+      break;
+    case 'i':
+      info.invert = 1;
+      break;
+    case 'f':
+      info.highpass = 1;
+      info.lambda = strtod(optarg, &p);
+      if (*p || info.lambda<0) {
+	fprintf(stderr, ""MKBITMAP": invalid filter radius -- %s\n", optarg);
+        exit(1);
+      }
+      break;
+    case 'n':
+      info.highpass = 0;
+      break;
+    case 'b':
+      info.lowpass = 1;
+      info.lambda1 = strtod(optarg, &p);
+      if (*p || info.lambda1<0) {
+	fprintf(stderr, ""MKBITMAP": invalid filter radius -- %s\n", optarg);
+        exit(1);
+      }
+      break;
+    case 's':
+      info.scale = strtol(optarg, &p, 0);
+      if (*p || info.scale<=0) {
+	fprintf(stderr, ""MKBITMAP": invalid scaling factor -- %s\n", optarg);
+        exit(1);
+      }
+      break;
+    case '1':
+      info.linear = 1;
+      break;
+    case '3':
+      info.linear = 0;
+      break;
+    case 'g':
+      info.bilevel = 0;
+      info.outext = ".pgm";
+      break;
+    case 't':
+      info.bilevel = 1;
+      info.outext = ".pbm";
+      info.level = strtod(optarg, &p);
+      if (*p || info.level<0) {
+	fprintf(stderr, ""MKBITMAP": invalid threshold -- %s\n", optarg);
+        exit(1);
+      }
+      break;
+    case '?':
+      fprintf(stderr, "Try --help for more info\n");
+      exit(1);
+      break;
+    default:
+      fprintf(stderr, ""MKBITMAP": Unimplemented option -- %c\n", c);
+      exit(1);
+    }
+  }
+  info.infiles = &av[optind];
+  info.infilecount = ac-optind;
+  return;
+}
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions for file handling */
+
+/* open a file for reading. Return stdin if filename is NULL or "-" */ 
+static FILE *my_fopen_read(char *filename) {
+  if (filename == NULL || strcmp(filename, "-") == 0) {
+    return stdin;
+  }
+  return fopen(filename, "rb");
+}
+
+/* open a file for writing. Return stdout if filename is NULL or "-" */ 
+static FILE *my_fopen_write(char *filename) {
+  if (filename == NULL || strcmp(filename, "-") == 0) {
+    return stdout;
+  }
+  return fopen(filename, "wb");
+}
+
+/* close a file, but do nothing is filename is NULL or "-" */
+static void my_fclose(FILE *f, char *filename) {
+  if (filename == NULL || strcmp(filename, "-") == 0) {
+    return;
+  }
+  fclose(f);
+}
+
+/* make output filename from input filename. Return an allocated value. */
+static char *make_outfilename(char *infile, char *ext) {
+  char *outfile;
+  char *p;
+
+  if (strcmp(infile, "-") == 0) {
+    return strdup("-");
+  }
+
+  outfile = (char *) malloc(strlen(infile)+strlen(ext)+5);
+  if (!outfile) {
+    return NULL;
+  }
+  strcpy(outfile, infile);
+  p = strrchr(outfile, '.');
+  if (p) {
+    *p = 0;
+  }
+  strcat(outfile, ext);
+
+  /* check that input and output filenames are different */
+  if (strcmp(infile, outfile) == 0) {
+    strcpy(outfile, infile);
+    strcat(outfile, "-out");
+  }
+
+  return outfile;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Main function */
+
+int main(int ac, char *av[]) {
+  FILE *fin, *fout;
+  int i;
+  char *outfile;
+
+  /* platform-specific initializations, e.g., set file i/o to binary */
+  platform_init();
+
+  /* process options */
+  dopts(ac, av);
+
+  /* there are several ways to call us:
+     mkbitmap                    -- stdin to stdout
+     mkbitmap -o outfile         -- stdin to outfile
+     mkbitmap file...            -- encode each file and generate outfile names
+     mkbitmap file... -o outfile -- concatenate files and write to outfile
+  */
+
+  if (info.infilecount == 0 && info.outfile == NULL) {  /* stdin to stdout */
+
+    process_file(stdin, stdout, "stdin", "stdout");
+    return 0;
+
+  } else if (info.infilecount == 0) {                  /* stdin to outfile */
+
+    fout = my_fopen_write(info.outfile);
+    if (!fout) {
+      fprintf(stderr, ""MKBITMAP": %s: %s\n", info.outfile, strerror(errno));
+      exit(2);
+    }
+    process_file(stdin, fout, "stdin", info.outfile);
+    my_fclose(fout, info.outfile);
+    free(info.outfile);
+    return 0;
+
+  } else if (info.outfile == NULL) {       /* infiles -> multiple outfiles */
+
+    for (i=0; i<info.infilecount; i++) {
+      outfile = make_outfilename(info.infiles[i], info.outext);
+      if (!outfile) {
+	fprintf(stderr, ""MKBITMAP": %s\n", strerror(errno));
+        exit(2);
+      }
+      fin = my_fopen_read(info.infiles[i]);
+      if (!fin) {
+	fprintf(stderr, ""MKBITMAP": %s: %s\n", info.infiles[i], strerror(errno));
+	exit(2);
+      }
+      fout = my_fopen_write(outfile);
+      if (!fout) {
+	fprintf(stderr, ""MKBITMAP": %s: %s\n", outfile, strerror(errno));
+	exit(2);
+      }
+      process_file(fin, fout, info.infiles[i], outfile);
+      my_fclose(fin, info.infiles[i]);
+      my_fclose(fout, outfile);
+      free(outfile);
+    }
+    return 0;
+
+  } else {                                    /* infiles to single outfile */
+
+    fout = my_fopen_write(info.outfile);
+    if (!fout) {
+      fprintf(stderr, ""MKBITMAP": %s: %s\n", info.outfile, strerror(errno));
+      exit(2);
+    }
+    for (i=0; i<info.infilecount; i++) {
+      fin = my_fopen_read(info.infiles[i]);
+      if (!fin) {
+	fprintf(stderr, ""MKBITMAP": %s: %s\n", info.infiles[i], strerror(errno));
+	exit(2);
+      }
+      process_file(fin, fout, info.infiles[i], info.outfile);
+      my_fclose(fin, info.infiles[i]);
+    }
+    my_fclose(fout, info.outfile);
+    free(info.outfile);
+    return 0;
+
+  }      
+
+  /* not reached */
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/platform.h b/Build/source/libs/potrace/potrace-src/src/platform.h
new file mode 100644
index 00000000000..4fa1155ac4e
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/platform.h
@@ -0,0 +1,38 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* this header file contains some platform dependent stuff */
+
+#ifndef PLATFORM_H
+#define PLATFORM_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+/* in Windows, set all file i/o to binary */
+#ifdef __MINGW32__
+#include <fcntl.h>
+unsigned int _CRT_fmode = _O_BINARY;
+static inline void platform_init(void) {
+  _setmode(_fileno(stdin), _O_BINARY);
+  _setmode(_fileno(stdout), _O_BINARY);
+}
+#else
+
+#ifdef __CYGWIN__
+#include <fcntl.h>
+#include <io.h>
+static inline void platform_init(void) {
+  setmode(0,O_BINARY); 
+  setmode(1,O_BINARY);
+}
+#else
+static inline void platform_init(void) {
+  /* NOP */
+}
+#endif
+#endif
+
+#endif /* PLATFORM_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/potracelib.c b/Build/source/libs/potrace/potrace-src/src/potracelib.c
new file mode 100644
index 00000000000..23f9669bd75
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/potracelib.c
@@ -0,0 +1,114 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "decompose.h"
+#include "trace.h"
+#include "progress.h"
+
+/* default parameters */
+static const potrace_param_t param_default = {
+  2,                             /* turdsize */
+  POTRACE_TURNPOLICY_MINORITY,   /* turnpolicy */
+  1.0,                           /* alphamax */
+  1,                             /* opticurve */
+  0.2,                           /* opttolerance */
+  {
+    NULL,                        /* callback function */
+    NULL,                        /* callback data */
+    0.0, 1.0,                    /* progress range */
+    0.0,                         /* granularity */
+  },
+};
+
+/* Return a fresh copy of the set of default parameters, or NULL on
+   failure with errno set. */
+potrace_param_t *potrace_param_default(void) {
+  potrace_param_t *p;
+
+  p = (potrace_param_t *) malloc(sizeof(potrace_param_t));
+  if (!p) {
+    return NULL;
+  }
+  memcpy(p, &param_default, sizeof(potrace_param_t));
+  return p;
+}
+
+/* On success, returns a Potrace state st with st->status ==
+   POTRACE_STATUS_OK. On failure, returns NULL if no Potrace state
+   could be created (with errno set), or returns an incomplete Potrace
+   state (with st->status == POTRACE_STATUS_INCOMPLETE, and with errno
+   set). Complete or incomplete Potrace state can be freed with
+   potrace_state_free(). */
+potrace_state_t *potrace_trace(const potrace_param_t *param, const potrace_bitmap_t *bm) {
+  int r;
+  path_t *plist = NULL;
+  potrace_state_t *st;
+  progress_t prog;
+  progress_t subprog;
+  
+  /* prepare private progress bar state */
+  prog.callback = param->progress.callback;
+  prog.data = param->progress.data;
+  prog.min = param->progress.min;
+  prog.max = param->progress.max;
+  prog.epsilon = param->progress.epsilon;
+  prog.d_prev = param->progress.min;
+
+  /* allocate state object */
+  st = (potrace_state_t *)malloc(sizeof(potrace_state_t));
+  if (!st) {
+    return NULL;
+  }
+
+  progress_subrange_start(0.0, 0.1, &prog, &subprog);
+
+  /* process the image */
+  r = bm_to_pathlist(bm, &plist, param, &subprog);
+  if (r) {
+    free(st);
+    return NULL;
+  }
+
+  st->status = POTRACE_STATUS_OK;
+  st->plist = plist;
+  st->priv = NULL;  /* private state currently unused */
+
+  progress_subrange_end(&prog, &subprog);
+
+  progress_subrange_start(0.1, 1.0, &prog, &subprog);
+
+  /* partial success. */
+  r = process_path(plist, param, &subprog);
+  if (r) {
+    st->status = POTRACE_STATUS_INCOMPLETE;
+  }
+
+  progress_subrange_end(&prog, &subprog);
+
+  return st;
+}
+
+/* free a Potrace state, without disturbing errno. */
+void potrace_state_free(potrace_state_t *st) {
+  pathlist_free(st->plist);
+  free(st);
+}
+
+/* free a parameter list, without disturbing errno. */
+void potrace_param_free(potrace_param_t *p) {
+  free(p);
+}
+
+char *potrace_version(void) {
+  return "potracelib "VERSION"";
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/potracelib.h b/Build/source/libs/potrace/potrace-src/src/potracelib.h
new file mode 100644
index 00000000000..0a6ddbf1f63
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/potracelib.h
@@ -0,0 +1,139 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifndef POTRACELIB_H
+#define POTRACELIB_H
+
+/* this file defines the API for the core Potrace library. For a more
+   detailed description of the API, see potracelib.pdf */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* ---------------------------------------------------------------------- */
+/* tracing parameters */
+
+/* turn policies */
+#define POTRACE_TURNPOLICY_BLACK 0
+#define POTRACE_TURNPOLICY_WHITE 1
+#define POTRACE_TURNPOLICY_LEFT 2
+#define POTRACE_TURNPOLICY_RIGHT 3
+#define POTRACE_TURNPOLICY_MINORITY 4
+#define POTRACE_TURNPOLICY_MAJORITY 5
+#define POTRACE_TURNPOLICY_RANDOM 6
+
+/* structure to hold progress bar callback data */
+struct potrace_progress_s {
+  void (*callback)(double progress, void *privdata); /* callback fn */
+  void *data;          /* callback function's private data */
+  double min, max;     /* desired range of progress, e.g. 0.0 to 1.0 */
+  double epsilon;      /* granularity: can skip smaller increments */
+};
+typedef struct potrace_progress_s potrace_progress_t;
+
+/* structure to hold tracing parameters */
+struct potrace_param_s {
+  int turdsize;        /* area of largest path to be ignored */
+  int turnpolicy;      /* resolves ambiguous turns in path decomposition */
+  double alphamax;     /* corner threshold */
+  int opticurve;       /* use curve optimization? */
+  double opttolerance; /* curve optimization tolerance */
+  potrace_progress_t progress; /* progress callback function */
+};
+typedef struct potrace_param_s potrace_param_t;
+
+/* ---------------------------------------------------------------------- */
+/* bitmaps */
+
+/* native word size */
+typedef unsigned long potrace_word;
+
+/* Internal bitmap format. The n-th scanline starts at scanline(n) =
+   (map + n*dy). Raster data is stored as a sequence of potrace_words
+   (NOT bytes). The leftmost bit of scanline n is the most significant
+   bit of scanline(n)[0]. */
+struct potrace_bitmap_s {
+  int w, h;              /* width and height, in pixels */
+  int dy;                /* words per scanline (not bytes) */
+  potrace_word *map;     /* raw data, dy*h words */
+};
+typedef struct potrace_bitmap_s potrace_bitmap_t;
+
+/* ---------------------------------------------------------------------- */
+/* curves */
+
+/* point */
+struct potrace_dpoint_s {
+  double x, y;
+};
+typedef struct potrace_dpoint_s potrace_dpoint_t;
+
+/* segment tags */
+#define POTRACE_CURVETO 1
+#define POTRACE_CORNER 2
+
+/* closed curve segment */
+struct potrace_curve_s {
+  int n;                    /* number of segments */
+  int *tag;                 /* tag[n]: POTRACE_CURVETO or POTRACE_CORNER */
+  potrace_dpoint_t (*c)[3]; /* c[n][3]: control points. 
+			       c[n][0] is unused for tag[n]=POTRACE_CORNER */
+};
+typedef struct potrace_curve_s potrace_curve_t;
+
+/* Linked list of signed curve segments. Also carries a tree structure. */
+struct potrace_path_s {
+  int area;                         /* area of the bitmap path */
+  int sign;                         /* '+' or '-', depending on orientation */
+  potrace_curve_t curve;            /* this path's vector data */
+
+  struct potrace_path_s *next;      /* linked list structure */
+
+  struct potrace_path_s *childlist; /* tree structure */
+  struct potrace_path_s *sibling;   /* tree structure */
+
+  struct potrace_privpath_s *priv;  /* private state */
+};
+typedef struct potrace_path_s potrace_path_t;  
+
+/* ---------------------------------------------------------------------- */
+/* Potrace state */
+
+#define POTRACE_STATUS_OK         0
+#define POTRACE_STATUS_INCOMPLETE 1
+
+struct potrace_state_s {
+  int status;                       
+  potrace_path_t *plist;            /* vector data */
+
+  struct potrace_privstate_s *priv; /* private state */
+};
+typedef struct potrace_state_s potrace_state_t;
+
+/* ---------------------------------------------------------------------- */
+/* API functions */
+
+/* get default parameters */
+potrace_param_t *potrace_param_default(void);
+
+/* free parameter set */
+void potrace_param_free(potrace_param_t *p);
+
+/* trace a bitmap*/
+potrace_state_t *potrace_trace(const potrace_param_t *param, 
+			       const potrace_bitmap_t *bm);
+
+/* free a Potrace state */
+void potrace_state_free(potrace_state_t *st);
+
+/* return a static plain text version string identifying this version
+   of potracelib */
+char *potrace_version(void);
+
+#ifdef  __cplusplus
+} /* end of extern "C" */
+#endif
+
+#endif /* POTRACELIB_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/potracelib_demo.c b/Build/source/libs/potrace/potrace-src/src/potracelib_demo.c
new file mode 100644
index 00000000000..65a787d61ce
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/potracelib_demo.c
@@ -0,0 +1,148 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* A simple and self-contained demo of the potracelib API */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+#include "potracelib.h"
+
+#define WIDTH 250
+#define HEIGHT 250
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary bitmap functions */
+
+/* macros for writing individual bitmap pixels */
+#define BM_WORDSIZE ((int)sizeof(potrace_word))
+#define BM_WORDBITS (8*BM_WORDSIZE)
+#define BM_HIBIT (((potrace_word)1)<<(BM_WORDBITS-1))
+#define bm_scanline(bm, y) ((bm)->map + (y)*(bm)->dy)
+#define bm_index(bm, x, y) (&bm_scanline(bm, y)[(x)/BM_WORDBITS])
+#define bm_mask(x) (BM_HIBIT >> ((x) & (BM_WORDBITS-1)))
+#define bm_range(x, a) ((int)(x) >= 0 && (int)(x) < (a))
+#define bm_safe(bm, x, y) (bm_range(x, (bm)->w) && bm_range(y, (bm)->h))
+#define BM_USET(bm, x, y) (*bm_index(bm, x, y) |= bm_mask(x))
+#define BM_UCLR(bm, x, y) (*bm_index(bm, x, y) &= ~bm_mask(x))
+#define BM_UPUT(bm, x, y, b) ((b) ? BM_USET(bm, x, y) : BM_UCLR(bm, x, y))
+#define BM_PUT(bm, x, y, b) (bm_safe(bm, x, y) ? BM_UPUT(bm, x, y, b) : 0)
+
+/* return new un-initialized bitmap. NULL with errno on error */
+static potrace_bitmap_t *bm_new(int w, int h) {
+  potrace_bitmap_t *bm;
+  int dy = (w + BM_WORDBITS - 1) / BM_WORDBITS;
+
+  bm = (potrace_bitmap_t *) malloc(sizeof(potrace_bitmap_t));
+  if (!bm) {
+    return NULL;
+  }
+  bm->w = w;
+  bm->h = h;
+  bm->dy = dy;
+  bm->map = (potrace_word *) calloc(h, dy * BM_WORDSIZE);
+  if (!bm->map) {
+    free(bm);
+    return NULL;
+  }
+  return bm;
+}
+
+/* free a bitmap */
+static void bm_free(potrace_bitmap_t *bm) {
+  if (bm != NULL) {
+    free(bm->map);
+  }
+  free(bm);
+}
+
+/* ---------------------------------------------------------------------- */
+/* demo */
+
+int main() {
+  int x, y, i;
+  potrace_bitmap_t *bm;
+  potrace_param_t *param;
+  potrace_path_t *p;
+  potrace_state_t *st;
+  int n, *tag;
+  potrace_dpoint_t (*c)[3];
+
+  /* create a bitmap */
+  bm = bm_new(WIDTH, HEIGHT);
+  if (!bm) {
+    fprintf(stderr, "Error allocating bitmap: %s\n", strerror(errno)); 
+    return 1;
+  }
+
+  /* fill the bitmap with some pattern */
+  for (y=0; y<HEIGHT; y++) {
+    for (x=0; x<WIDTH; x++) {
+      BM_PUT(bm, x, y, ((x*x + y*y*y) % 10000 < 5000) ? 1 : 0);
+    }
+  }
+
+  /* set tracing parameters, starting from defaults */
+  param = potrace_param_default();
+  if (!param) {
+    fprintf(stderr, "Error allocating parameters: %s\n", strerror(errno)); 
+    return 1;
+  }
+  param->turdsize = 0;
+
+  /* trace the bitmap */
+  st = potrace_trace(param, bm);
+  if (!st || st->status != POTRACE_STATUS_OK) {
+    fprintf(stderr, "Error tracing bitmap: %s\n", strerror(errno));
+    return 1;
+  }
+  bm_free(bm);
+  
+  /* output vector data, e.g. as a rudimentary EPS file */
+  printf("%%!PS-Adobe-3.0 EPSF-3.0\n");
+  printf("%%%%BoundingBox: 0 0 %d %d\n", WIDTH, HEIGHT);
+  printf("gsave\n");
+
+  /* draw each curve */
+  p = st->plist;
+  while (p != NULL) {
+    n = p->curve.n;
+    tag = p->curve.tag;
+    c = p->curve.c;
+    printf("%f %f moveto\n", c[n-1][2].x, c[n-1][2].y);
+    for (i=0; i<n; i++) {
+      switch (tag[i]) {
+      case POTRACE_CORNER:
+	printf("%f %f lineto\n", c[i][1].x, c[i][1].y);
+	printf("%f %f lineto\n", c[i][2].x, c[i][2].y);
+	break;
+      case POTRACE_CURVETO:
+	printf("%f %f %f %f %f %f curveto\n", 
+	       c[i][0].x, c[i][0].y,
+	       c[i][1].x, c[i][1].y,
+	       c[i][2].x, c[i][2].y);
+	break;
+      }
+    }
+    /* at the end of a group of a positive path and its negative
+       children, fill. */
+    if (p->next == NULL || p->next->sign == '+') {
+      printf("0 setgray fill\n");
+    }
+    p = p->next;
+  }
+  printf("grestore\n");
+  printf("%%EOF\n");
+  
+  potrace_state_free(st);
+  potrace_param_free(param);
+
+  return 0;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/progress.h b/Build/source/libs/potrace/potrace-src/src/progress.h
new file mode 100644
index 00000000000..dd93d79207a
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/progress.h
@@ -0,0 +1,79 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* operations on potrace_progress_t objects, which are defined in
+   potracelib.h. Note: the code attempts to minimize runtime overhead
+   when no progress monitoring was requested. It also tries to
+   minimize excessive progress calculations beneath the "epsilon"
+   threshold. */
+
+#ifndef PROGRESS_H
+#define PROGRESS_H
+
+/* structure to hold progress bar callback data */
+struct progress_s {
+  void (*callback)(double progress, void *privdata); /* callback fn */
+  void *data;          /* callback function's private data */
+  double min, max;     /* desired range of progress, e.g. 0.0 to 1.0 */
+  double epsilon;      /* granularity: can skip smaller increments */
+  double b;            /* upper limit of subrange in superrange units */
+  double d_prev;       /* previous value of d */
+};
+typedef struct progress_s progress_t;
+
+/* notify given progress object of current progress. Note that d is
+   given in the 0.0-1.0 range, which will be scaled and translated to
+   the progress object's range. */
+static inline void progress_update(double d, progress_t *prog) {
+  double d_scaled;
+
+  if (prog != NULL && prog->callback != NULL) {
+    d_scaled = prog->min * (1-d) + prog->max * d;
+    if (d == 1.0 || d_scaled >= prog->d_prev + prog->epsilon) {
+      prog->callback(prog->min * (1-d) + prog->max * d, prog->data);
+      prog->d_prev = d_scaled;
+    }
+  }
+}
+
+/* start a subrange of the given progress object. The range is
+   narrowed to [a..b], relative to 0.0-1.0 coordinates. If new range
+   is below granularity threshold, disable further subdivisions. */
+static inline void progress_subrange_start(double a, double b, const progress_t *prog, progress_t *sub) {
+  double min, max;
+
+  if (prog == NULL || prog->callback == NULL) {
+    sub->callback = NULL;
+    return;
+  }
+
+  min = prog->min * (1-a) + prog->max * a;
+  max = prog->min * (1-b) + prog->max * b;
+
+  if (max - min < prog->epsilon) {
+    sub->callback = NULL;    /* no further progress info in subrange */
+    sub->b = b;
+    return;
+  }
+  sub->callback = prog->callback;
+  sub->data = prog->data;
+  sub->epsilon = prog->epsilon;
+  sub->min = min;
+  sub->max = max;
+  sub->d_prev = prog->d_prev;
+  return;
+}
+
+static inline void progress_subrange_end(progress_t *prog, progress_t *sub) {
+  if (prog != NULL && prog->callback != NULL) {
+    if (sub->callback == NULL) {
+      progress_update(sub->b, prog);
+    } else {
+      prog->d_prev = sub->d_prev;
+    }
+  }    
+}
+
+#endif /* PROGRESS_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/progress_bar.c b/Build/source/libs/potrace/potrace-src/src/progress_bar.c
new file mode 100644
index 00000000000..acf75658a4f
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/progress_bar.c
@@ -0,0 +1,207 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* functions to render a progress bar for main.c. We provide a
+   standard and a simplified progress bar. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "potracelib.h"
+#include "progress_bar.h"
+
+/* ---------------------------------------------------------------------- */
+/* vt100 progress bar */
+
+#define COL0 "\033[G"  /* reset cursor to column 0 */
+
+struct vt100_progress_s {
+  char name[22];          /* filename for status bar */
+  double dnext;           /* threshold value for next tick */
+};
+typedef struct vt100_progress_s vt100_progress_t;
+
+/* print a progress bar using vt100 control characters. This is a
+   callback function that is potentially called often; thus, it has
+   been optimized for the typical case, which is when the progress bar
+   does not need updating. */
+static void vt100_progress(double d, void *data) {
+  vt100_progress_t *p = (vt100_progress_t *)data;
+  static char b[] = "========================================";
+  int tick;    /* number of visible tickmarks, 0..40 */
+  int perc;    /* visible percentage, 0..100 */
+
+  /* note: the 0.01 and 0.025 ensure that we always end on 40
+     tickmarks and 100%, despite any rounding errors. The 0.995
+     ensures that tick always increases when d >= p->dnext. */
+  if (d >= p->dnext) {
+    tick = (int) floor(d*40+0.01);
+    perc = (int) floor(d*100+0.025);
+    fprintf(stderr, "%-21s |%-40s| %d%% "COL0"", p->name, b+40-tick, perc);
+    fflush(stderr);
+    p->dnext = (tick+0.995) / 40.0;
+  }
+}
+
+/* Initialize progress bar. Return 0 on success or 1 on failure with
+   errno set. */
+static int init_vt100_progress(potrace_progress_t *prog, const char *filename, int count) {
+  vt100_progress_t *p;
+  const char *q, *s;
+  int len;
+
+  p = (vt100_progress_t *) malloc(sizeof(vt100_progress_t));
+  if (!p) {
+    return 1;
+  }
+
+  /* initialize callback function's data */
+  p->dnext = 0;
+
+  if (count != 0) {
+    sprintf(p->name, " (p.%d):", count+1);
+  } else {
+    s = filename;
+    if ((q = strrchr(s, '/')) != NULL) {
+      s = q+1;
+    }
+    len = strlen(s);
+    strncpy(p->name, s, 21);
+    p->name[20] = 0;
+    if (len > 20) {
+      p->name[17] = '.';
+      p->name[18] = '.';
+      p->name[19] = '.';
+    }
+    strcat(p->name, ":");
+  }
+
+  /* initialize progress parameters */
+  prog->callback = &vt100_progress;
+  prog->data = (void *)p;
+  prog->min = 0.0;
+  prog->max = 1.0;
+  prog->epsilon = 0.0;
+  
+  /* draw first progress bar */
+  vt100_progress(0.0, prog->data);
+  return 0;
+}
+
+/* Finalize the progress bar. */
+static void term_vt100_progress(potrace_progress_t *prog) {
+  fprintf(stderr, "\n");
+  fflush(stderr);
+  free(prog->data);
+  return;
+}
+
+/* progress bar interface structure */
+static progress_bar_t progress_bar_vt100_struct = {
+  init_vt100_progress,
+  term_vt100_progress,
+};
+progress_bar_t *progress_bar_vt100 = &progress_bar_vt100_struct;
+
+/* ---------------------------------------------------------------------- */
+/* another progress bar for dumb terminals */
+
+struct simplified_progress_s {
+  int n;                  /* number of ticks displayed so far */
+  double dnext;           /* threshold value for next tick */
+};
+typedef struct simplified_progress_s simplified_progress_t;
+
+/* print a simplified progress bar, not using any special tty control
+   codes. Optimized for frequent calling. */
+static void simplified_progress(double d, void *data) {
+  simplified_progress_t *p = (simplified_progress_t *)data;
+  int tick;    /* number of visible tickmarks, 0..40 */
+
+  /* note: the 0.01 and 0.025 ensure that we always end on 40
+     tickmarks and 100%, despite any rounding errors. The 0.995
+     ensures that tick always increases when d >= p->dnext. */
+  if (d >= p->dnext) {
+    tick = (int) floor(d*40+0.01);
+    while (p->n < tick) {
+      fputc('=', stderr);
+      p->n++;
+    }
+    fflush(stderr);
+    p->dnext = (tick+0.995) / 40.0;
+  }
+}
+
+/* Initialize parameters for simplified progress bar. Return 0 on
+   success or 1 on error with errno set. */
+static int init_simplified_progress(potrace_progress_t *prog, const char *filename, int count) {
+  simplified_progress_t *p;
+  const char *q, *s;
+  int len;
+  char buf[22];
+
+  p = (simplified_progress_t *) malloc(sizeof(simplified_progress_t));
+  if (!p) {
+    return 1;
+  }
+
+  /* initialize callback function's data */
+  p->n = 0;
+  p->dnext = 0;
+
+  if (count != 0) {
+    sprintf(buf, " (p.%d):", count+1);
+  } else {
+    s = filename;
+    if ((q = strrchr(s, '/')) != NULL) {
+      s = q+1;
+    }
+    len = strlen(s);
+    strncpy(buf, s, 21);
+    buf[20] = 0;
+    if (len > 20) {
+      buf[17] = '.';
+      buf[18] = '.';
+      buf[19] = '.';
+    }
+    strcat(buf, ":");
+  }
+
+  fprintf(stderr, "%-21s |", buf);
+
+  /* initialize progress parameters */
+  prog->callback = &simplified_progress;
+  prog->data = (void *)p;
+  prog->min = 0.0;
+  prog->max = 1.0;
+  prog->epsilon = 0.0;
+  
+  /* draw first progress bar */
+  simplified_progress(0.0, prog->data);
+  return 0;
+}
+
+static void term_simplified_progress(potrace_progress_t *prog) {
+  simplified_progress_t *p = (simplified_progress_t *)prog->data;
+
+  simplified_progress(1.0, (void *)p);
+  fprintf(stderr, "| 100%%\n");
+  fflush(stderr);
+  free(p);
+  return;
+}
+
+/* progress bar interface structure */
+static progress_bar_t progress_bar_simplified_struct = {
+  init_simplified_progress,
+  term_simplified_progress,
+};
+progress_bar_t *progress_bar_simplified = &progress_bar_simplified_struct;
+
diff --git a/Build/source/libs/potrace/potrace-src/src/progress_bar.h b/Build/source/libs/potrace/potrace-src/src/progress_bar.h
new file mode 100644
index 00000000000..c28cb8444f5
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/progress_bar.h
@@ -0,0 +1,26 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* functions to render a progress bar for main.c. We provide a
+   standard and a simplified progress bar. */
+
+#ifndef PROGRESS_BAR_H
+#define PROGRESS_BAR_H
+
+#include "potracelib.h"
+
+/* structure to hold a progress bar interface */
+struct progress_bar_s {
+  int (*init)(potrace_progress_t *prog, const char *filename, int count);
+  void (*term)(potrace_progress_t *prog);
+};
+typedef struct progress_bar_s progress_bar_t;
+
+extern progress_bar_t *progress_bar_vt100;
+extern progress_bar_t *progress_bar_simplified;
+
+
+
+#endif /* PROGRESS_BAR_H */
+
diff --git a/Build/source/libs/potrace/potrace-src/src/render.c b/Build/source/libs/potrace/potrace-src/src/render.c
new file mode 100644
index 00000000000..38ba1c70024
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/render.c
@@ -0,0 +1,246 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include <string.h>
+
+#include "render.h"
+#include "greymap.h"
+#include "auxiliary.h"
+
+/* ---------------------------------------------------------------------- */
+/* routines for anti-aliased rendering of curves */
+
+/* we use the following method. Given a point (x,y) (with real-valued
+   coordinates) in the plane, let (xi,yi) be the integer part of the
+   coordinates, i.e., xi=floor(x), yi=floor(y). Define a path from
+   (x,y) to infinity as follows: path(x,y) =
+   (x,y)--(xi+1,y)--(xi+1,yi)--(+infty,yi).  Now as the point (x,y)
+   moves smoothly across the plane, the path path(x,y) sweeps
+   (non-smoothly) across a certain area. We proportionately blacken
+   the area as the path moves "downward", and we whiten the area as
+   the path moves "upward". This way, after the point has traversed a
+   closed curve, the interior of the curve has been darkened
+   (counterclockwise movement) or lightened (clockwise movement). (The
+   "grey shift" is actually proportional to the winding number). By
+   choosing the above path with mostly integer coordinates, we achieve
+   that only pixels close to (x,y) receive grey values and are subject
+   to round-off errors. The grey value of pixels far away from (x,y)
+   is always in "integer" (where 0=black, 1=white).  As a special
+   trick, we keep an accumulator rm->a1, which holds a double value to
+   be added to the grey value to be added to the current pixel
+   (xi,yi).  Only when changing "current" pixels, we convert this
+   double value to an integer. This way we avoid round-off errors at
+   the meeting points of line segments. Another speedup measure is
+   that we sometimes use the rm->incrow_buf array to postpone
+   incrementing or decrementing an entire row. If incrow_buf[y]=x+1!=0,
+   then all the pixels (x,y),(x+1,y),(x+2,y),... are scheduled to be
+   incremented/decremented (which one is the case will be clear from 
+   context). This keeps the greymap operations reasonably local. */
+
+/* allocate a new rendering state */
+render_t *render_new(greymap_t *gm) {
+  render_t *rm;
+
+  rm = (render_t *) malloc(sizeof(render_t));
+  if (!rm) {
+    return NULL;
+  }
+  memset(rm, 0, sizeof(render_t));
+  rm->gm = gm;
+  rm->incrow_buf = (int *) calloc(gm->h, sizeof(int));
+  if (!rm->incrow_buf) {
+    free(rm);
+    return NULL;
+  }
+  memset(rm->incrow_buf, 0, gm->h * sizeof(int));
+  return rm;
+}
+
+/* free a given rendering state. Note: this does not free the
+   underlying greymap. */
+void render_free(render_t *rm) {
+  free(rm->incrow_buf);
+  free(rm);
+}
+
+/* close path */
+void render_close(render_t *rm) {
+  if (rm->x0 != rm->x1 || rm->y0 != rm->y1) {
+    render_lineto(rm, rm->x0, rm->y0);
+  }
+  GM_INC(rm->gm, rm->x0i, rm->y0i, (rm->a0+rm->a1)*255);
+
+  /* assert (rm->x0i != rm->x1i || rm->y0i != rm->y1i); */
+  
+  /* the persistent state is now undefined */
+}
+
+/* move point */
+void render_moveto(render_t *rm, double x, double y) {
+  /* close the previous path */
+  render_close(rm);
+
+  rm->x0 = rm->x1 = x;
+  rm->y0 = rm->y1 = y;
+  rm->x0i = (int)floor(rm->x0);
+  rm->x1i = (int)floor(rm->x1);
+  rm->y0i = (int)floor(rm->y0);
+  rm->y1i = (int)floor(rm->y1);
+  rm->a0 = rm->a1 = 0;
+}
+
+/* add b to pixels (x,y) and all pixels to the right of it. However,
+   use rm->incrow_buf as a buffer to economize on multiple calls */
+static void incrow(render_t *rm, int x, int y, int b) {
+  int i, x0;
+
+  if (y < 0 || y >= rm->gm->h) {
+    return;
+  }
+
+  if (x < 0) {
+    x = 0;
+  } else if (x > rm->gm->w) {
+    x = rm->gm->w;
+  }
+  if (rm->incrow_buf[y] == 0) {
+    rm->incrow_buf[y] = x+1; /* store x+1 so that we can use 0 for "vacant" */
+    return;
+  }
+  x0 = rm->incrow_buf[y]-1;
+  rm->incrow_buf[y] = 0;
+  if (x0 < x) {
+    for (i=x0; i<x; i++) {
+      GM_INC(rm->gm, i, y, -b);
+    }
+  } else {
+    for (i=x; i<x0; i++) {
+      GM_INC(rm->gm, i, y, b);
+    }
+  }    
+}
+
+/* render a straight line */
+void render_lineto(render_t *rm, double x2, double y2) {
+  int x2i, y2i;
+  double t0=2, s0=2;
+  int sn, tn;
+  double ss=2, ts=2;
+  double r0, r1;
+  int i, j;
+  int rxi, ryi;
+  int s;
+
+  x2i = (int)floor(x2);
+  y2i = (int)floor(y2);
+
+  sn = abs(x2i - rm->x1i);
+  tn = abs(y2i - rm->y1i);
+
+  if (sn) {
+    s0 = ((x2>rm->x1 ? rm->x1i+1 : rm->x1i) - rm->x1)/(x2-rm->x1);
+    ss = fabs(1.0/(x2-rm->x1));
+  }
+  if (tn) {
+    t0 = ((y2>rm->y1 ? rm->y1i+1 : rm->y1i) - rm->y1)/(y2-rm->y1);
+    ts = fabs(1.0/(y2-rm->y1));
+  }
+
+  r0 = 0;
+
+  i = 0;
+  j = 0;
+
+  rxi = rm->x1i;
+  ryi = rm->y1i;
+
+  while (i<sn || j<tn) {
+    if (j>=tn || (i<sn && s0+i*ss < t0+j*ts)) {
+      r1 = s0+i*ss;
+      i++;
+      s = 1;
+    } else {
+      r1 = t0+j*ts;
+      j++;
+      s = 0;
+    }
+    /* render line from r0 to r1 segment of (rm->x1,rm->y1)..(x2,y2) */
+    
+    /* move point to r1 */
+    rm->a1 += (r1-r0)*(y2-rm->y1)*(rxi+1-((r0+r1)/2.0*(x2-rm->x1)+rm->x1));
+
+    /* move point across pixel boundary */
+    if (s && x2>rm->x1) {
+      GM_INC(rm->gm, rxi, ryi, rm->a1*255);
+      rm->a1 = 0;
+      rxi++;
+      rm->a1 += rm->y1+r1*(y2-rm->y1)-ryi;
+    } else if (!s && y2>rm->y1) {
+      GM_INC(rm->gm, rxi, ryi, rm->a1*255);
+      rm->a1 = 0;
+      incrow(rm, rxi+1, ryi, 255);
+      ryi++;
+    } else if (s && x2<=rm->x1) {
+      rm->a1 -= rm->y1+r1*(y2-rm->y1)-ryi;
+      GM_INC(rm->gm, rxi, ryi, rm->a1*255);
+      rm->a1 = 0;
+      rxi--;
+    } else if (!s && y2<=rm->y1) {
+      GM_INC(rm->gm, rxi, ryi, rm->a1*255);
+      rm->a1 = 0;
+      ryi--;
+      incrow(rm, rxi+1, ryi, -255);
+    }
+
+    r0 = r1;
+  }
+  
+  /* move point to (x2,y2) */
+  
+  r1 = 1;
+  rm->a1 += (r1-r0)*(y2-rm->y1)*(rxi+1-((r0+r1)/2.0*(x2-rm->x1)+rm->x1));
+
+  rm->x1i = x2i;
+  rm->y1i = y2i;
+  rm->x1 = x2;
+  rm->y1 = y2;
+
+  /* assert (rxi != rm->x1i || ryi != rm->y1i); */
+}
+
+/* render a Bezier curve. */
+void render_curveto(render_t *rm, double x2, double y2, double x3, double y3, double x4, double y4) {
+  double x1, y1, dd0, dd1, dd, delta, e2, epsilon, t;
+
+  x1 = rm->x1;  /* starting point */
+  y1 = rm->y1;
+
+  /* we approximate the curve by small line segments. The interval
+     size, epsilon, is determined on the fly so that the distance
+     between the true curve and its approximation does not exceed the
+     desired accuracy delta. */
+
+  delta = .1;  /* desired accuracy, in pixels */
+
+  /* let dd = maximal value of 2nd derivative over curve - this must
+     occur at an endpoint. */
+  dd0 = sq(x1-2*x2+x3) + sq(y1-2*y2+y3);
+  dd1 = sq(x2-2*x3+x4) + sq(y2-2*y3+y4);
+  dd = 6*sqrt(max(dd0, dd1));
+  e2 = 8*delta <= dd ? 8*delta/dd : 1;
+  epsilon = sqrt(e2);  /* necessary interval size */
+
+  for (t=epsilon; t<1; t+=epsilon) {
+    render_lineto(rm, x1*cu(1-t)+3*x2*sq(1-t)*t+3*x3*(1-t)*sq(t)+x4*cu(t),
+		  y1*cu(1-t)+3*y2*sq(1-t)*t+3*y3*(1-t)*sq(t)+y4*cu(t));
+  }
+  render_lineto(rm, x4, y4);
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/render.h b/Build/source/libs/potrace/potrace-src/src/render.h
new file mode 100644
index 00000000000..0caaedff629
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/render.h
@@ -0,0 +1,27 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef RENDER_H
+#define RENDER_H
+
+#include "greymap.h"
+
+struct render_s {
+  greymap_t *gm;
+  double x0, y0, x1, y1;
+  int x0i, y0i, x1i, y1i;
+  double a0, a1;
+  int *incrow_buf;
+};
+typedef struct render_s render_t;
+
+render_t *render_new(greymap_t *gm);
+void render_free(render_t *rm);
+void render_close(render_t *rm);
+void render_moveto(render_t *rm, double x, double y);
+void render_lineto(render_t *rm, double x, double y);
+void render_curveto(render_t *rm, double x2, double y2, double x3, double y3, double x4, double y4);
+
+#endif /* RENDER_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/trace.c b/Build/source/libs/potrace/potrace-src/src/trace.c
new file mode 100644
index 00000000000..7f92458284d
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/trace.c
@@ -0,0 +1,1249 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* transform jaggy paths into smooth curves */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <math.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "potracelib.h"
+#include "curve.h"
+#include "lists.h"
+#include "auxiliary.h"
+#include "trace.h"
+#include "progress.h"
+
+#define INFTY 10000000	/* it suffices that this is longer than any
+			   path; it need not be really infinite */
+#define COS179 -0.999847695156	 /* the cosine of 179 degrees */
+
+/* ---------------------------------------------------------------------- */
+#define SAFE_CALLOC(var, n, typ) \
+  if ((var = (typ *)calloc(n, sizeof(typ))) == NULL) goto calloc_error 
+
+/* ---------------------------------------------------------------------- */
+/* auxiliary functions */
+
+/* return a direction that is 90 degrees counterclockwise from p2-p0,
+   but then restricted to one of the major wind directions (n, nw, w, etc) */
+static inline point_t dorth_infty(dpoint_t p0, dpoint_t p2) {
+  point_t r;
+  
+  r.y = sign(p2.x-p0.x);
+  r.x = -sign(p2.y-p0.y);
+
+  return r;
+}
+
+/* return (p1-p0)x(p2-p0), the area of the parallelogram */
+static inline double dpara(dpoint_t p0, dpoint_t p1, dpoint_t p2) {
+  double x1, y1, x2, y2;
+
+  x1 = p1.x-p0.x;
+  y1 = p1.y-p0.y;
+  x2 = p2.x-p0.x;
+  y2 = p2.y-p0.y;
+
+  return x1*y2 - x2*y1;
+}
+
+/* ddenom/dpara have the property that the square of radius 1 centered
+   at p1 intersects the line p0p2 iff |dpara(p0,p1,p2)| <= ddenom(p0,p2) */
+static inline double ddenom(dpoint_t p0, dpoint_t p2) {
+  point_t r = dorth_infty(p0, p2);
+
+  return r.y*(p2.x-p0.x) - r.x*(p2.y-p0.y);
+}
+
+/* return 1 if a <= b < c < a, in a cyclic sense (mod n) */
+static inline int cyclic(int a, int b, int c) {
+  if (a<=c) {
+    return (a<=b && b<c);
+  } else {
+    return (a<=b || b<c);
+  }
+}
+
+/* determine the center and slope of the line i..j. Assume i<j. Needs
+   "sum" components of p to be set. */
+static void pointslope(privpath_t *pp, int i, int j, dpoint_t *ctr, dpoint_t *dir) {
+  /* assume i<j */
+
+  int n = pp->len;
+  sums_t *sums = pp->sums;
+
+  double x, y, x2, xy, y2;
+  double k;
+  double a, b, c, lambda2, l;
+  int r=0; /* rotations from i to j */
+
+  while (j>=n) {
+    j-=n;
+    r+=1;
+  }
+  while (i>=n) {
+    i-=n;
+    r-=1;
+  }
+  while (j<0) {
+    j+=n;
+    r-=1;
+  }
+  while (i<0) {
+    i+=n;
+    r+=1;
+  }
+  
+  x = sums[j+1].x-sums[i].x+r*sums[n].x;
+  y = sums[j+1].y-sums[i].y+r*sums[n].y;
+  x2 = sums[j+1].x2-sums[i].x2+r*sums[n].x2;
+  xy = sums[j+1].xy-sums[i].xy+r*sums[n].xy;
+  y2 = sums[j+1].y2-sums[i].y2+r*sums[n].y2;
+  k = j+1-i+r*n;
+  
+  ctr->x = x/k;
+  ctr->y = y/k;
+
+  a = (x2-(double)x*x/k)/k;
+  b = (xy-(double)x*y/k)/k;
+  c = (y2-(double)y*y/k)/k;
+  
+  lambda2 = (a+c+sqrt((a-c)*(a-c)+4*b*b))/2; /* larger e.value */
+
+  /* now find e.vector for lambda2 */
+  a -= lambda2;
+  c -= lambda2;
+
+  if (fabs(a) >= fabs(c)) {
+    l = sqrt(a*a+b*b);
+    if (l!=0) {
+      dir->x = -b/l;
+      dir->y = a/l;
+    }
+  } else {
+    l = sqrt(c*c+b*b);
+    if (l!=0) {
+      dir->x = -c/l;
+      dir->y = b/l;
+    }
+  }
+  if (l==0) {
+    dir->x = dir->y = 0;   /* sometimes this can happen when k=4:
+			      the two eigenvalues coincide */
+  }
+}
+
+/* the type of (affine) quadratic forms, represented as symmetric 3x3
+   matrices.  The value of the quadratic form at a vector (x,y) is v^t
+   Q v, where v = (x,y,1)^t. */
+typedef double quadform_t[3][3];
+
+/* Apply quadratic form Q to vector w = (w.x,w.y) */
+static inline double quadform(quadform_t Q, dpoint_t w) {
+  double v[3];
+  int i, j;
+  double sum;
+
+  v[0] = w.x;
+  v[1] = w.y;
+  v[2] = 1;
+  sum = 0.0;
+
+  for (i=0; i<3; i++) {
+    for (j=0; j<3; j++) {
+      sum += v[i] * Q[i][j] * v[j];
+    }
+  }
+  return sum;
+}
+
+/* calculate p1 x p2 */
+static inline int xprod(point_t p1, point_t p2) {
+  return p1.x*p2.y - p1.y*p2.x;
+}
+
+/* calculate (p1-p0)x(p3-p2) */
+static inline double cprod(dpoint_t p0, dpoint_t p1, dpoint_t p2, dpoint_t p3) {
+  double x1, y1, x2, y2;
+
+  x1 = p1.x - p0.x;
+  y1 = p1.y - p0.y;
+  x2 = p3.x - p2.x;
+  y2 = p3.y - p2.y;
+
+  return x1*y2 - x2*y1;
+}
+
+/* calculate (p1-p0)*(p2-p0) */
+static inline double iprod(dpoint_t p0, dpoint_t p1, dpoint_t p2) {
+  double x1, y1, x2, y2;
+
+  x1 = p1.x - p0.x;
+  y1 = p1.y - p0.y;
+  x2 = p2.x - p0.x;
+  y2 = p2.y - p0.y;
+
+  return x1*x2 + y1*y2;
+}
+
+/* calculate (p1-p0)*(p3-p2) */
+static inline double iprod1(dpoint_t p0, dpoint_t p1, dpoint_t p2, dpoint_t p3) {
+  double x1, y1, x2, y2;
+
+  x1 = p1.x - p0.x;
+  y1 = p1.y - p0.y;
+  x2 = p3.x - p2.x;
+  y2 = p3.y - p2.y;
+
+  return x1*x2 + y1*y2;
+}
+
+/* calculate distance between two points */
+static inline double ddist(dpoint_t p, dpoint_t q) {
+  return sqrt(sq(p.x-q.x)+sq(p.y-q.y));
+}
+
+/* calculate point of a bezier curve */
+static inline dpoint_t bezier(double t, dpoint_t p0, dpoint_t p1, dpoint_t p2, dpoint_t p3) {
+  double s = 1-t;
+  dpoint_t res;
+
+  /* Note: a good optimizing compiler (such as gcc-3) reduces the
+     following to 16 multiplications, using common subexpression
+     elimination. */
+
+  res.x = s*s*s*p0.x + 3*(s*s*t)*p1.x + 3*(t*t*s)*p2.x + t*t*t*p3.x;
+  res.y = s*s*s*p0.y + 3*(s*s*t)*p1.y + 3*(t*t*s)*p2.y + t*t*t*p3.y;
+
+  return res;
+}
+
+/* calculate the point t in [0..1] on the (convex) bezier curve
+   (p0,p1,p2,p3) which is tangent to q1-q0. Return -1.0 if there is no
+   solution in [0..1]. */
+static double tangent(dpoint_t p0, dpoint_t p1, dpoint_t p2, dpoint_t p3, dpoint_t q0, dpoint_t q1) {
+  double A, B, C;   /* (1-t)^2 A + 2(1-t)t B + t^2 C = 0 */
+  double a, b, c;   /* a t^2 + b t + c = 0 */
+  double d, s, r1, r2;
+
+  A = cprod(p0, p1, q0, q1);
+  B = cprod(p1, p2, q0, q1);
+  C = cprod(p2, p3, q0, q1);
+
+  a = A - 2*B + C;
+  b = -2*A + 2*B;
+  c = A;
+  
+  d = b*b - 4*a*c;
+
+  if (a==0 || d<0) {
+    return -1.0;
+  }
+
+  s = sqrt(d);
+
+  r1 = (-b + s) / (2 * a);
+  r2 = (-b - s) / (2 * a);
+
+  if (r1 >= 0 && r1 <= 1) {
+    return r1;
+  } else if (r2 >= 0 && r2 <= 1) {
+    return r2;
+  } else {
+    return -1.0;
+  }
+}
+
+/* ---------------------------------------------------------------------- */
+/* Preparation: fill in the sum* fields of a path (used for later
+   rapid summing). Return 0 on success, 1 with errno set on
+   failure. */
+static int calc_sums(privpath_t *pp) {
+  int i, x, y;
+  int n = pp->len;
+
+  SAFE_CALLOC(pp->sums, pp->len+1, sums_t);
+
+  /* origin */
+  pp->x0 = pp->pt[0].x;
+  pp->y0 = pp->pt[0].y;
+
+  /* preparatory computation for later fast summing */
+  pp->sums[0].x2 = pp->sums[0].xy = pp->sums[0].y2 = pp->sums[0].x = pp->sums[0].y = 0;
+  for (i=0; i<n; i++) {
+    x = pp->pt[i].x - pp->x0;
+    y = pp->pt[i].y - pp->y0;
+    pp->sums[i+1].x = pp->sums[i].x + x;
+    pp->sums[i+1].y = pp->sums[i].y + y;
+    pp->sums[i+1].x2 = pp->sums[i].x2 + x*x;
+    pp->sums[i+1].xy = pp->sums[i].xy + x*y;
+    pp->sums[i+1].y2 = pp->sums[i].y2 + y*y;
+  }
+  return 0;  
+
+ calloc_error:
+  return 1;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Stage 1: determine the straight subpaths (Sec. 2.2.1). Fill in the
+   "lon" component of a path object (based on pt/len).	For each i,
+   lon[i] is the furthest index such that a straight line can be drawn
+   from i to lon[i]. Return 1 on error with errno set, else 0. */
+
+/* this algorithm depends on the fact that the existence of straight
+   subpaths is a triplewise property. I.e., there exists a straight
+   line through squares i0,...,in iff there exists a straight line
+   through i,j,k, for all i0<=i<j<k<=in. (Proof?) */
+
+/* this implementation of calc_lon is O(n^2). It replaces an older
+   O(n^3) version. A "constraint" means that future points must
+   satisfy xprod(constraint[0], cur) >= 0 and xprod(constraint[1],
+   cur) <= 0. */
+
+/* Remark for Potrace 1.1: the current implementation of calc_lon is
+   more complex than the implementation found in Potrace 1.0, but it
+   is considerably faster. The introduction of the "nc" data structure
+   means that we only have to test the constraints for "corner"
+   points. On a typical input file, this speeds up the calc_lon
+   function by a factor of 31.2, thereby decreasing its time share
+   within the overall Potrace algorithm from 72.6% to 7.82%, and
+   speeding up the overall algorithm by a factor of 3.36. On another
+   input file, calc_lon was sped up by a factor of 6.7, decreasing its
+   time share from 51.4% to 13.61%, and speeding up the overall
+   algorithm by a factor of 1.78. In any case, the savings are
+   substantial. */
+
+/* returns 0 on success, 1 on error with errno set */
+static int calc_lon(privpath_t *pp) {
+  point_t *pt = pp->pt;
+  int n = pp->len;
+  int i, j, k, k1;
+  int ct[4], dir;
+  point_t constraint[2];
+  point_t cur;
+  point_t off;
+  int *pivk = NULL;  /* pivk[n] */
+  int *nc = NULL;    /* nc[n]: next corner */
+  point_t dk;  /* direction of k-k1 */
+  int a, b, c, d;
+
+  SAFE_CALLOC(pivk, n, int);
+  SAFE_CALLOC(nc, n, int);
+
+  /* initialize the nc data structure. Point from each point to the
+     furthest future point to which it is connected by a vertical or
+     horizontal segment. We take advantage of the fact that there is
+     always a direction change at 0 (due to the path decomposition
+     algorithm). But even if this were not so, there is no harm, as
+     in practice, correctness does not depend on the word "furthest"
+     above.  */
+  k = 0;
+  for (i=n-1; i>=0; i--) {
+    if (pt[i].x != pt[k].x && pt[i].y != pt[k].y) {
+      k = i+1;  /* necessarily i<n-1 in this case */
+    }
+    nc[i] = k;
+  }
+
+  SAFE_CALLOC(pp->lon, n, int);
+
+  /* determine pivot points: for each i, let pivk[i] be the furthest k
+     such that all j with i<j<k lie on a line connecting i,k. */
+  
+  for (i=n-1; i>=0; i--) {
+    ct[0] = ct[1] = ct[2] = ct[3] = 0;
+
+    /* keep track of "directions" that have occurred */
+    dir = (3+3*(pt[mod(i+1,n)].x-pt[i].x)+(pt[mod(i+1,n)].y-pt[i].y))/2;
+    ct[dir]++;
+
+    constraint[0].x = 0;
+    constraint[0].y = 0;
+    constraint[1].x = 0;
+    constraint[1].y = 0;
+
+    /* find the next k such that no straight line from i to k */
+    k = nc[i];
+    k1 = i;
+    while (1) {
+      
+      dir = (3+3*sign(pt[k].x-pt[k1].x)+sign(pt[k].y-pt[k1].y))/2;
+      ct[dir]++;
+
+      /* if all four "directions" have occurred, cut this path */
+      if (ct[0] && ct[1] && ct[2] && ct[3]) {
+	pivk[i] = k1;
+	goto foundk;
+      }
+
+      cur.x = pt[k].x - pt[i].x;
+      cur.y = pt[k].y - pt[i].y;
+
+      /* see if current constraint is violated */
+      if (xprod(constraint[0], cur) < 0 || xprod(constraint[1], cur) > 0) {
+	goto constraint_viol;
+      }
+
+      /* else, update constraint */
+      if (abs(cur.x) <= 1 && abs(cur.y) <= 1) {
+	/* no constraint */
+      } else {
+	off.x = cur.x + ((cur.y>=0 && (cur.y>0 || cur.x<0)) ? 1 : -1);
+	off.y = cur.y + ((cur.x<=0 && (cur.x<0 || cur.y<0)) ? 1 : -1);
+	if (xprod(constraint[0], off) >= 0) {
+	  constraint[0] = off;
+	}
+	off.x = cur.x + ((cur.y<=0 && (cur.y<0 || cur.x<0)) ? 1 : -1);
+	off.y = cur.y + ((cur.x>=0 && (cur.x>0 || cur.y<0)) ? 1 : -1);
+	if (xprod(constraint[1], off) <= 0) {
+	  constraint[1] = off;
+	}
+      }	
+      k1 = k;
+      k = nc[k1];
+      if (!cyclic(k,i,k1)) {
+	break;
+      }
+    }
+  constraint_viol:
+    /* k1 was the last "corner" satisfying the current constraint, and
+       k is the first one violating it. We now need to find the last
+       point along k1..k which satisfied the constraint. */
+    dk.x = sign(pt[k].x-pt[k1].x);
+    dk.y = sign(pt[k].y-pt[k1].y);
+    cur.x = pt[k1].x - pt[i].x;
+    cur.y = pt[k1].y - pt[i].y;
+    /* find largest integer j such that xprod(constraint[0], cur+j*dk)
+       >= 0 and xprod(constraint[1], cur+j*dk) <= 0. Use bilinearity
+       of xprod. */
+    a = xprod(constraint[0], cur);
+    b = xprod(constraint[0], dk);
+    c = xprod(constraint[1], cur);
+    d = xprod(constraint[1], dk);
+    /* find largest integer j such that a+j*b>=0 and c+j*d<=0. This
+       can be solved with integer arithmetic. */
+    j = INFTY;
+    if (b<0) {
+      j = floordiv(a,-b);
+    }
+    if (d>0) {
+      j = min(j, floordiv(-c,d));
+    }
+    pivk[i] = mod(k1+j,n);
+  foundk:
+    ;
+  } /* for i */
+
+  /* clean up: for each i, let lon[i] be the largest k such that for
+     all i' with i<=i'<k, i'<k<=pivk[i']. */
+
+  j=pivk[n-1];
+  pp->lon[n-1]=j;
+  for (i=n-2; i>=0; i--) {
+    if (cyclic(i+1,pivk[i],j)) {
+      j=pivk[i];
+    }
+    pp->lon[i]=j;
+  }
+
+  for (i=n-1; cyclic(mod(i+1,n),j,pp->lon[i]); i--) {
+    pp->lon[i] = j;
+  }
+
+  free(pivk);
+  free(nc);
+  return 0;
+
+ calloc_error:
+  free(pivk);
+  free(nc);
+  return 1;
+}
+
+
+/* ---------------------------------------------------------------------- */
+/* Stage 2: calculate the optimal polygon (Sec. 2.2.2-2.2.4). */ 
+
+/* Auxiliary function: calculate the penalty of an edge from i to j in
+   the given path. This needs the "lon" and "sum*" data. */
+
+static double penalty3(privpath_t *pp, int i, int j) {
+  int n = pp->len;
+  point_t *pt = pp->pt;
+  sums_t *sums = pp->sums;
+
+  /* assume 0<=i<j<=n  */
+  double x, y, x2, xy, y2;
+  double k;
+  double a, b, c, s;
+  double px, py, ex, ey;
+
+  int r = 0; /* rotations from i to j */
+
+  if (j>=n) {
+    j -= n;
+    r = 1;
+  }
+  
+  /* critical inner loop: the "if" gives a 4.6 percent speedup */
+  if (r == 0) {
+    x = sums[j+1].x - sums[i].x;
+    y = sums[j+1].y - sums[i].y;
+    x2 = sums[j+1].x2 - sums[i].x2;
+    xy = sums[j+1].xy - sums[i].xy;
+    y2 = sums[j+1].y2 - sums[i].y2;
+    k = j+1 - i;
+  } else {
+    x = sums[j+1].x - sums[i].x + sums[n].x;
+    y = sums[j+1].y - sums[i].y + sums[n].y;
+    x2 = sums[j+1].x2 - sums[i].x2 + sums[n].x2;
+    xy = sums[j+1].xy - sums[i].xy + sums[n].xy;
+    y2 = sums[j+1].y2 - sums[i].y2 + sums[n].y2;
+    k = j+1 - i + n;
+  } 
+
+  px = (pt[i].x + pt[j].x) / 2.0 - pt[0].x;
+  py = (pt[i].y + pt[j].y) / 2.0 - pt[0].y;
+  ey = (pt[j].x - pt[i].x);
+  ex = -(pt[j].y - pt[i].y);
+
+  a = ((x2 - 2*x*px) / k + px*px);
+  b = ((xy - x*py - y*px) / k + px*py);
+  c = ((y2 - 2*y*py) / k + py*py);
+  
+  s = ex*ex*a + 2*ex*ey*b + ey*ey*c;
+
+  return sqrt(s);
+}
+
+/* find the optimal polygon. Fill in the m and po components. Return 1
+   on failure with errno set, else 0. Non-cyclic version: assumes i=0
+   is in the polygon. Fixme: implement cyclic version. */
+static int bestpolygon(privpath_t *pp)
+{
+  int i, j, m, k;     
+  int n = pp->len;
+  double *pen = NULL; /* pen[n+1]: penalty vector */
+  int *prev = NULL;   /* prev[n+1]: best path pointer vector */
+  int *clip0 = NULL;  /* clip0[n]: longest segment pointer, non-cyclic */
+  int *clip1 = NULL;  /* clip1[n+1]: backwards segment pointer, non-cyclic */
+  int *seg0 = NULL;    /* seg0[m+1]: forward segment bounds, m<=n */
+  int *seg1 = NULL;   /* seg1[m+1]: backward segment bounds, m<=n */
+  double thispen;
+  double best;
+  int c;
+
+  SAFE_CALLOC(pen, n+1, double);
+  SAFE_CALLOC(prev, n+1, int);
+  SAFE_CALLOC(clip0, n, int);
+  SAFE_CALLOC(clip1, n+1, int);
+  SAFE_CALLOC(seg0, n+1, int);
+  SAFE_CALLOC(seg1, n+1, int);
+
+  /* calculate clipped paths */
+  for (i=0; i<n; i++) {
+    c = mod(pp->lon[mod(i-1,n)]-1,n);
+    if (c == i) {
+      c = mod(i+1,n);
+    }
+    if (c < i) {
+      clip0[i] = n;
+    } else {
+      clip0[i] = c;
+    }
+  }
+
+  /* calculate backwards path clipping, non-cyclic. j <= clip0[i] iff
+     clip1[j] <= i, for i,j=0..n. */
+  j = 1;
+  for (i=0; i<n; i++) {
+    while (j <= clip0[i]) {
+      clip1[j] = i;
+      j++;
+    }
+  }
+
+  /* calculate seg0[j] = longest path from 0 with j segments */
+  i = 0;
+  for (j=0; i<n; j++) {
+    seg0[j] = i;
+    i = clip0[i];
+  }
+  seg0[j] = n;
+  m = j;
+
+  /* calculate seg1[j] = longest path to n with m-j segments */
+  i = n;
+  for (j=m; j>0; j--) {
+    seg1[j] = i;
+    i = clip1[i];
+  }
+  seg1[0] = 0;
+
+  /* now find the shortest path with m segments, based on penalty3 */
+  /* note: the outer 2 loops jointly have at most n iterations, thus
+     the worst-case behavior here is quadratic. In practice, it is
+     close to linear since the inner loop tends to be short. */
+  pen[0]=0;
+  for (j=1; j<=m; j++) {
+    for (i=seg1[j]; i<=seg0[j]; i++) {
+      best = -1;
+      for (k=seg0[j-1]; k>=clip1[i]; k--) {
+	thispen = penalty3(pp, k, i) + pen[k];
+	if (best < 0 || thispen < best) {
+	  prev[i] = k;
+	  best = thispen;
+	}
+      }
+      pen[i] = best;
+    }
+  }
+
+  pp->m = m;
+  SAFE_CALLOC(pp->po, m, int);
+
+  /* read off shortest path */
+  for (i=n, j=m-1; i>0; j--) {
+    i = prev[i];
+    pp->po[j] = i;
+  }
+
+  free(pen);
+  free(prev);
+  free(clip0);
+  free(clip1);
+  free(seg0);
+  free(seg1);
+  return 0;
+  
+ calloc_error:
+  free(pen);
+  free(prev);
+  free(clip0);
+  free(clip1);
+  free(seg0);
+  free(seg1);
+  return 1;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Stage 3: vertex adjustment (Sec. 2.3.1). */
+
+/* Adjust vertices of optimal polygon: calculate the intersection of
+   the two "optimal" line segments, then move it into the unit square
+   if it lies outside. Return 1 with errno set on error; 0 on
+   success. */
+
+static int adjust_vertices(privpath_t *pp) {
+  int m = pp->m;
+  int *po = pp->po;
+  int n = pp->len;
+  point_t *pt = pp->pt;
+  int x0 = pp->x0;
+  int y0 = pp->y0;
+
+  dpoint_t *ctr = NULL;      /* ctr[m] */
+  dpoint_t *dir = NULL;      /* dir[m] */
+  quadform_t *q = NULL;      /* q[m] */
+  double v[3];
+  double d;
+  int i, j, k, l;
+  dpoint_t s;
+  int r;
+
+  SAFE_CALLOC(ctr, m, dpoint_t);
+  SAFE_CALLOC(dir, m, dpoint_t);
+  SAFE_CALLOC(q, m, quadform_t);
+
+  r = privcurve_init(&pp->curve, m);
+  if (r) {
+    goto calloc_error;
+  }
+  
+  /* calculate "optimal" point-slope representation for each line
+     segment */
+  for (i=0; i<m; i++) {
+    j = po[mod(i+1,m)];
+    j = mod(j-po[i],n)+po[i];
+    pointslope(pp, po[i], j, &ctr[i], &dir[i]);
+  }
+
+  /* represent each line segment as a singular quadratic form; the
+     distance of a point (x,y) from the line segment will be
+     (x,y,1)Q(x,y,1)^t, where Q=q[i]. */
+  for (i=0; i<m; i++) {
+    d = sq(dir[i].x) + sq(dir[i].y);
+    if (d == 0.0) {
+      for (j=0; j<3; j++) {
+	for (k=0; k<3; k++) {
+	  q[i][j][k] = 0;
+	}
+      }
+    } else {
+      v[0] = dir[i].y;
+      v[1] = -dir[i].x;
+      v[2] = - v[1] * ctr[i].y - v[0] * ctr[i].x;
+      for (l=0; l<3; l++) {
+	for (k=0; k<3; k++) {
+	  q[i][l][k] = v[l] * v[k] / d;
+	}
+      }
+    }
+  }
+
+  /* now calculate the "intersections" of consecutive segments.
+     Instead of using the actual intersection, we find the point
+     within a given unit square which minimizes the square distance to
+     the two lines. */
+  for (i=0; i<m; i++) {
+    quadform_t Q;
+    dpoint_t w;
+    double dx, dy;
+    double det;
+    double min, cand; /* minimum and candidate for minimum of quad. form */
+    double xmin, ymin;	/* coordinates of minimum */
+    int z;
+
+    /* let s be the vertex, in coordinates relative to x0/y0 */
+    s.x = pt[po[i]].x-x0;
+    s.y = pt[po[i]].y-y0;
+
+    /* intersect segments i-1 and i */
+
+    j = mod(i-1,m);
+
+    /* add quadratic forms */
+    for (l=0; l<3; l++) {
+      for (k=0; k<3; k++) {
+	Q[l][k] = q[j][l][k] + q[i][l][k];
+      }
+    }
+    
+    while(1) {
+      /* minimize the quadratic form Q on the unit square */
+      /* find intersection */
+
+#ifdef HAVE_GCC_LOOP_BUG
+      /* work around gcc bug #12243 */
+      free(NULL);
+#endif
+      
+      det = Q[0][0]*Q[1][1] - Q[0][1]*Q[1][0];
+      if (det != 0.0) {
+	w.x = (-Q[0][2]*Q[1][1] + Q[1][2]*Q[0][1]) / det;
+	w.y = ( Q[0][2]*Q[1][0] - Q[1][2]*Q[0][0]) / det;
+	break;
+      }
+
+      /* matrix is singular - lines are parallel. Add another,
+	 orthogonal axis, through the center of the unit square */
+      if (Q[0][0]>Q[1][1]) {
+	v[0] = -Q[0][1];
+	v[1] = Q[0][0];
+      } else if (Q[1][1]) {
+	v[0] = -Q[1][1];
+	v[1] = Q[1][0];
+      } else {
+	v[0] = 1;
+	v[1] = 0;
+      }
+      d = sq(v[0]) + sq(v[1]);
+      v[2] = - v[1] * s.y - v[0] * s.x;
+      for (l=0; l<3; l++) {
+	for (k=0; k<3; k++) {
+	  Q[l][k] += v[l] * v[k] / d;
+	}
+      }
+    }
+    dx = fabs(w.x-s.x);
+    dy = fabs(w.y-s.y);
+    if (dx <= .5 && dy <= .5) {
+      pp->curve.vertex[i].x = w.x+x0;
+      pp->curve.vertex[i].y = w.y+y0;
+      continue;
+    }
+
+    /* the minimum was not in the unit square; now minimize quadratic
+       on boundary of square */
+    min = quadform(Q, s);
+    xmin = s.x;
+    ymin = s.y;
+
+    if (Q[0][0] == 0.0) {
+      goto fixx;
+    }
+    for (z=0; z<2; z++) {   /* value of the y-coordinate */
+      w.y = s.y-0.5+z;
+      w.x = - (Q[0][1] * w.y + Q[0][2]) / Q[0][0];
+      dx = fabs(w.x-s.x);
+      cand = quadform(Q, w);
+      if (dx <= .5 && cand < min) {
+	min = cand;
+	xmin = w.x;
+	ymin = w.y;
+      }
+    }
+  fixx:
+    if (Q[1][1] == 0.0) {
+      goto corners;
+    }
+    for (z=0; z<2; z++) {   /* value of the x-coordinate */
+      w.x = s.x-0.5+z;
+      w.y = - (Q[1][0] * w.x + Q[1][2]) / Q[1][1];
+      dy = fabs(w.y-s.y);
+      cand = quadform(Q, w);
+      if (dy <= .5 && cand < min) {
+	min = cand;
+	xmin = w.x;
+	ymin = w.y;
+      }
+    }
+  corners:
+    /* check four corners */
+    for (l=0; l<2; l++) {
+      for (k=0; k<2; k++) {
+	w.x = s.x-0.5+l;
+	w.y = s.y-0.5+k;
+	cand = quadform(Q, w);
+	if (cand < min) {
+	  min = cand;
+	  xmin = w.x;
+	  ymin = w.y;
+	}
+      }
+    }
+
+    pp->curve.vertex[i].x = xmin + x0;
+    pp->curve.vertex[i].y = ymin + y0;
+    continue;
+  }
+
+  free(ctr);
+  free(dir);
+  free(q);
+  return 0;
+
+ calloc_error:
+  free(ctr);
+  free(dir);
+  free(q);
+  return 1;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Stage 4: smoothing and corner analysis (Sec. 2.3.3) */
+
+/* reverse orientation of a path */
+static void reverse(privcurve_t *curve) {
+  int m = curve->n;
+  int i, j;
+  dpoint_t tmp;
+
+  for (i=0, j=m-1; i<j; i++, j--) {
+    tmp = curve->vertex[i];
+    curve->vertex[i] = curve->vertex[j];
+    curve->vertex[j] = tmp;
+  }
+}
+
+/* Always succeeds */
+static void smooth(privcurve_t *curve, double alphamax) {
+  int m = curve->n;
+
+  int i, j, k;
+  double dd, denom, alpha;
+  dpoint_t p2, p3, p4;
+
+  /* examine each vertex and find its best fit */
+  for (i=0; i<m; i++) {
+    j = mod(i+1, m);
+    k = mod(i+2, m);
+    p4 = interval(1/2.0, curve->vertex[k], curve->vertex[j]);
+
+    denom = ddenom(curve->vertex[i], curve->vertex[k]);
+    if (denom != 0.0) {
+      dd = dpara(curve->vertex[i], curve->vertex[j], curve->vertex[k]) / denom;
+      dd = fabs(dd);
+      alpha = dd>1 ? (1 - 1.0/dd) : 0;
+      alpha = alpha / 0.75;
+    } else {
+      alpha = 4/3.0;
+    }
+    curve->alpha0[j] = alpha;	 /* remember "original" value of alpha */
+
+    if (alpha >= alphamax) {  /* pointed corner */
+      curve->tag[j] = POTRACE_CORNER;
+      curve->c[j][1] = curve->vertex[j];
+      curve->c[j][2] = p4;
+    } else {
+      if (alpha < 0.55) {
+	alpha = 0.55;
+      } else if (alpha > 1) {
+	alpha = 1;
+      }
+      p2 = interval(.5+.5*alpha, curve->vertex[i], curve->vertex[j]);
+      p3 = interval(.5+.5*alpha, curve->vertex[k], curve->vertex[j]);
+      curve->tag[j] = POTRACE_CURVETO;
+      curve->c[j][0] = p2;
+      curve->c[j][1] = p3;
+      curve->c[j][2] = p4;
+    }
+    curve->alpha[j] = alpha;	/* store the "cropped" value of alpha */
+    curve->beta[j] = 0.5;
+  }
+  curve->alphacurve = 1;
+
+  return;
+}
+
+/* ---------------------------------------------------------------------- */
+/* Stage 5: Curve optimization (Sec. 2.4) */
+
+/* a private type for the result of opti_penalty */
+struct opti_s {
+  double pen;	   /* penalty */
+  dpoint_t c[2];   /* curve parameters */
+  double t, s;	   /* curve parameters */
+  double alpha;	   /* curve parameter */
+};
+typedef struct opti_s opti_t;
+
+/* calculate best fit from i+.5 to j+.5.  Assume i<j (cyclically).
+   Return 0 and set badness and parameters (alpha, beta), if
+   possible. Return 1 if impossible. */
+static int opti_penalty(privpath_t *pp, int i, int j, opti_t *res, double opttolerance, int *convc, double *areac) {
+  int m = pp->curve.n;
+  int k, k1, k2, conv, i1;
+  double area, alpha, d, d1, d2;
+  dpoint_t p0, p1, p2, p3, pt;
+  double A, R, A1, A2, A3, A4;
+  double s, t;
+
+  /* check convexity, corner-freeness, and maximum bend < 179 degrees */
+
+  if (i==j) {  /* sanity - a full loop can never be an opticurve */
+    return 1;
+  }
+
+  k = i;
+  i1 = mod(i+1, m);
+  k1 = mod(k+1, m);
+  conv = convc[k1];
+  if (conv == 0) {
+    return 1;
+  }
+  d = ddist(pp->curve.vertex[i], pp->curve.vertex[i1]);
+  for (k=k1; k!=j; k=k1) {
+    k1 = mod(k+1, m);
+    k2 = mod(k+2, m);
+    if (convc[k1] != conv) {
+      return 1;
+    }
+    if (sign(cprod(pp->curve.vertex[i], pp->curve.vertex[i1], pp->curve.vertex[k1], pp->curve.vertex[k2])) != conv) {
+      return 1;
+    }
+    if (iprod1(pp->curve.vertex[i], pp->curve.vertex[i1], pp->curve.vertex[k1], pp->curve.vertex[k2]) < d * ddist(pp->curve.vertex[k1], pp->curve.vertex[k2]) * COS179) {
+      return 1;
+    }
+  }
+
+  /* the curve we're working in: */
+  p0 = pp->curve.c[mod(i,m)][2];
+  p1 = pp->curve.vertex[mod(i+1,m)];
+  p2 = pp->curve.vertex[mod(j,m)];
+  p3 = pp->curve.c[mod(j,m)][2];
+
+  /* determine its area */
+  area = areac[j] - areac[i];
+  area -= dpara(pp->curve.vertex[0], pp->curve.c[i][2], pp->curve.c[j][2])/2;
+  if (i>=j) {
+    area += areac[m];
+  }
+
+  /* find intersection o of p0p1 and p2p3. Let t,s such that o =
+     interval(t,p0,p1) = interval(s,p3,p2). Let A be the area of the
+     triangle (p0,o,p3). */
+
+  A1 = dpara(p0, p1, p2);
+  A2 = dpara(p0, p1, p3);
+  A3 = dpara(p0, p2, p3);
+  /* A4 = dpara(p1, p2, p3); */
+  A4 = A1+A3-A2;    
+  
+  if (A2 == A1) {  /* this should never happen */
+    return 1;
+  }
+
+  t = A3/(A3-A4);
+  s = A2/(A2-A1);
+  A = A2 * t / 2.0;
+  
+  if (A == 0.0) {  /* this should never happen */
+    return 1;
+  }
+
+  R = area / A;	 /* relative area */
+  alpha = 2 - sqrt(4 - R / 0.3);  /* overall alpha for p0-o-p3 curve */
+
+  res->c[0] = interval(t * alpha, p0, p1);
+  res->c[1] = interval(s * alpha, p3, p2);
+  res->alpha = alpha;
+  res->t = t;
+  res->s = s;
+
+  p1 = res->c[0];
+  p2 = res->c[1];  /* the proposed curve is now (p0,p1,p2,p3) */
+
+  res->pen = 0;
+
+  /* calculate penalty */
+  /* check tangency with edges */
+  for (k=mod(i+1,m); k!=j; k=k1) {
+    k1 = mod(k+1,m);
+    t = tangent(p0, p1, p2, p3, pp->curve.vertex[k], pp->curve.vertex[k1]);
+    if (t<-.5) {
+      return 1;
+    }
+    pt = bezier(t, p0, p1, p2, p3);
+    d = ddist(pp->curve.vertex[k], pp->curve.vertex[k1]);
+    if (d == 0.0) {  /* this should never happen */
+      return 1;
+    }
+    d1 = dpara(pp->curve.vertex[k], pp->curve.vertex[k1], pt) / d;
+    if (fabs(d1) > opttolerance) {
+      return 1;
+    }
+    if (iprod(pp->curve.vertex[k], pp->curve.vertex[k1], pt) < 0 || iprod(pp->curve.vertex[k1], pp->curve.vertex[k], pt) < 0) {
+      return 1;
+    }
+    res->pen += sq(d1);
+  }
+
+  /* check corners */
+  for (k=i; k!=j; k=k1) {
+    k1 = mod(k+1,m);
+    t = tangent(p0, p1, p2, p3, pp->curve.c[k][2], pp->curve.c[k1][2]);
+    if (t<-.5) {
+      return 1;
+    }
+    pt = bezier(t, p0, p1, p2, p3);
+    d = ddist(pp->curve.c[k][2], pp->curve.c[k1][2]);
+    if (d == 0.0) {  /* this should never happen */
+      return 1;
+    }
+    d1 = dpara(pp->curve.c[k][2], pp->curve.c[k1][2], pt) / d;
+    d2 = dpara(pp->curve.c[k][2], pp->curve.c[k1][2], pp->curve.vertex[k1]) / d;
+    d2 *= 0.75 * pp->curve.alpha[k1];
+    if (d2 < 0) {
+      d1 = -d1;
+      d2 = -d2;
+    }
+    if (d1 < d2 - opttolerance) {
+      return 1;
+    }
+    if (d1 < d2) {
+      res->pen += sq(d1 - d2);
+    }
+  }
+
+  return 0;
+}
+
+/* optimize the path p, replacing sequences of Bezier segments by a
+   single segment when possible. Return 0 on success, 1 with errno set
+   on failure. */
+static int opticurve(privpath_t *pp, double opttolerance) {
+  int m = pp->curve.n;
+  int *pt = NULL;     /* pt[m+1] */
+  double *pen = NULL; /* pen[m+1] */
+  int *len = NULL;    /* len[m+1] */
+  opti_t *opt = NULL; /* opt[m+1] */
+  int om;
+  int i,j,r;
+  opti_t o;
+  dpoint_t p0;
+  int i1;
+  double area;
+  double alpha;
+  double *s = NULL;
+  double *t = NULL;
+
+  int *convc = NULL; /* conv[m]: pre-computed convexities */
+  double *areac = NULL; /* cumarea[m+1]: cache for fast area computation */
+
+  SAFE_CALLOC(pt, m+1, int);
+  SAFE_CALLOC(pen, m+1, double);
+  SAFE_CALLOC(len, m+1, int);
+  SAFE_CALLOC(opt, m+1, opti_t);
+  SAFE_CALLOC(convc, m, int);
+  SAFE_CALLOC(areac, m+1, double);
+
+  /* pre-calculate convexity: +1 = right turn, -1 = left turn, 0 = corner */
+  for (i=0; i<m; i++) {
+    if (pp->curve.tag[i] == POTRACE_CURVETO) {
+      convc[i] = sign(dpara(pp->curve.vertex[mod(i-1,m)], pp->curve.vertex[i], pp->curve.vertex[mod(i+1,m)]));
+    } else {
+      convc[i] = 0;
+    }
+  }
+
+  /* pre-calculate areas */
+  area = 0.0;
+  areac[0] = 0.0;
+  p0 = pp->curve.vertex[0];
+  for (i=0; i<m; i++) {
+    i1 = mod(i+1, m);
+    if (pp->curve.tag[i1] == POTRACE_CURVETO) {
+      alpha = pp->curve.alpha[i1];
+      area += 0.3*alpha*(4-alpha)*dpara(pp->curve.c[i][2], pp->curve.vertex[i1], pp->curve.c[i1][2])/2;
+      area += dpara(p0, pp->curve.c[i][2], pp->curve.c[i1][2])/2;
+    }
+    areac[i+1] = area;
+  }
+
+  pt[0] = -1;
+  pen[0] = 0;
+  len[0] = 0;
+
+  /* Fixme: we always start from a fixed point -- should find the best
+     curve cyclically */
+
+  for (j=1; j<=m; j++) {
+    /* calculate best path from 0 to j */
+    pt[j] = j-1;
+    pen[j] = pen[j-1];
+    len[j] = len[j-1]+1;
+
+    for (i=j-2; i>=0; i--) {
+      r = opti_penalty(pp, i, mod(j,m), &o, opttolerance, convc, areac);
+      if (r) {
+	break;
+      }
+      if (len[j] > len[i]+1 || (len[j] == len[i]+1 && pen[j] > pen[i] + o.pen)) {
+	pt[j] = i;
+	pen[j] = pen[i] + o.pen;
+	len[j] = len[i] + 1;
+	opt[j] = o;
+      }
+    }
+  }
+  om = len[m];
+  r = privcurve_init(&pp->ocurve, om);
+  if (r) {
+    goto calloc_error;
+  }
+  SAFE_CALLOC(s, om, double);
+  SAFE_CALLOC(t, om, double);
+
+  j = m;
+  for (i=om-1; i>=0; i--) {
+    if (pt[j]==j-1) {
+      pp->ocurve.tag[i]     = pp->curve.tag[mod(j,m)];
+      pp->ocurve.c[i][0]    = pp->curve.c[mod(j,m)][0];
+      pp->ocurve.c[i][1]    = pp->curve.c[mod(j,m)][1];
+      pp->ocurve.c[i][2]    = pp->curve.c[mod(j,m)][2];
+      pp->ocurve.vertex[i]  = pp->curve.vertex[mod(j,m)];
+      pp->ocurve.alpha[i]   = pp->curve.alpha[mod(j,m)];
+      pp->ocurve.alpha0[i]  = pp->curve.alpha0[mod(j,m)];
+      pp->ocurve.beta[i]    = pp->curve.beta[mod(j,m)];
+      s[i] = t[i] = 1.0;
+    } else {
+      pp->ocurve.tag[i] = POTRACE_CURVETO;
+      pp->ocurve.c[i][0] = opt[j].c[0];
+      pp->ocurve.c[i][1] = opt[j].c[1];
+      pp->ocurve.c[i][2] = pp->curve.c[mod(j,m)][2];
+      pp->ocurve.vertex[i] = interval(opt[j].s, pp->curve.c[mod(j,m)][2], pp->curve.vertex[mod(j,m)]);
+      pp->ocurve.alpha[i] = opt[j].alpha;
+      pp->ocurve.alpha0[i] = opt[j].alpha;
+      s[i] = opt[j].s;
+      t[i] = opt[j].t;
+    }
+    j = pt[j];
+  }
+
+  /* calculate beta parameters */
+  for (i=0; i<om; i++) {
+    i1 = mod(i+1,om);
+    pp->ocurve.beta[i] = s[i] / (s[i] + t[i1]);
+  }
+  pp->ocurve.alphacurve = 1;
+
+  free(pt);
+  free(pen);
+  free(len);
+  free(opt);
+  free(s);
+  free(t);
+  free(convc);
+  free(areac);
+  return 0;
+
+ calloc_error:
+  free(pt);
+  free(pen);
+  free(len);
+  free(opt);
+  free(s);
+  free(t);
+  free(convc);
+  free(areac);
+  return 1;
+}
+
+/* ---------------------------------------------------------------------- */
+
+#define TRY(x) if (x) goto try_error
+
+/* return 0 on success, 1 on error with errno set. */
+int process_path(path_t *plist, const potrace_param_t *param, progress_t *progress) {
+  path_t *p;
+  double nn = 0, cn = 0;
+
+  if (progress->callback) {
+    /* precompute task size for progress estimates */
+    nn = 0;
+    list_forall (p, plist) {
+      nn += p->priv->len;
+    }
+    cn = 0;
+  }
+  
+  /* call downstream function with each path */
+  list_forall (p, plist) {
+    TRY(calc_sums(p->priv));
+    TRY(calc_lon(p->priv));
+    TRY(bestpolygon(p->priv));
+    TRY(adjust_vertices(p->priv));
+    if (p->sign == '-') {   /* reverse orientation of negative paths */
+      reverse(&p->priv->curve);
+    }
+    smooth(&p->priv->curve, param->alphamax);
+    if (param->opticurve) {
+      TRY(opticurve(p->priv, param->opttolerance));
+      p->priv->fcurve = &p->priv->ocurve;
+    } else {
+      p->priv->fcurve = &p->priv->curve;
+    }
+    privcurve_to_curve(p->priv->fcurve, &p->curve);
+
+    if (progress->callback) {
+      cn += p->priv->len;
+      progress_update(cn/nn, progress);
+    }
+  }
+
+  progress_update(1.0, progress);
+
+  return 0;
+
+ try_error:
+  return 1;
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/trace.h b/Build/source/libs/potrace/potrace-src/src/trace.h
new file mode 100644
index 00000000000..c53cdd10f25
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/trace.h
@@ -0,0 +1,15 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef TRACE_H
+#define TRACE_H
+
+#include "potracelib.h"
+#include "progress.h"
+#include "curve.h"
+
+int process_path(path_t *plist, const potrace_param_t *param, progress_t *progress);
+
+#endif /* TRACE_H */
diff --git a/Build/source/libs/potrace/potrace-src/src/trans.c b/Build/source/libs/potrace/potrace-src/src/trans.c
new file mode 100644
index 00000000000..a3a9d95995a
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/trans.c
@@ -0,0 +1,127 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+/* calculations with coordinate transformations and bounding boxes */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <math.h>
+#include <string.h>
+
+#include "trans.h"
+#include "bbox.h"
+
+/* rotate the coordinate system counterclockwise by alpha degrees. The
+   new bounding box will be the smallest box containing the rotated
+   old bounding box */
+void trans_rotate(trans_t *r, double alpha) {
+  double s, c, x0, x1, y0, y1, o0, o1;
+  trans_t t_struct;
+  trans_t *t = &t_struct;
+
+  memcpy(t, r, sizeof(trans_t));
+
+  s = sin(alpha/180*M_PI);
+  c = cos(alpha/180*M_PI);
+
+  /* apply the transformation matrix to the sides of the bounding box */
+  x0 = c * t->bb[0];
+  x1 = s * t->bb[0];
+  y0 = -s * t->bb[1];
+  y1 = c * t->bb[1];
+
+  /* determine new bounding box, and origin of old bb within new bb */
+  r->bb[0] = fabs(x0) + fabs(y0);
+  r->bb[1] = fabs(x1) + fabs(y1);
+  o0 = - min(x0,0) - min(y0,0);
+  o1 = - min(x1,0) - min(y1,0);
+
+  r->orig[0] = o0 + c * t->orig[0] - s * t->orig[1];
+  r->orig[1] = o1 + s * t->orig[0] + c * t->orig[1];
+  r->x[0] = c * t->x[0] - s * t->x[1];
+  r->x[1] = s * t->x[0] + c * t->x[1];
+  r->y[0] = c * t->y[0] - s * t->y[1];
+  r->y[1] = s * t->y[0] + c * t->y[1];
+}
+
+/* return the standard cartesian coordinate system for an w x h rectangle. */
+void trans_from_rect(trans_t *r, double w, double h) {
+  r->bb[0] = w;
+  r->bb[1] = h;
+  r->orig[0] = 0.0;
+  r->orig[1] = 0.0;
+  r->x[0] = 1.0;
+  r->x[1] = 0.0;
+  r->y[0] = 0.0;
+  r->y[1] = 1.0;
+  r->scalex = 1.0;
+  r->scaley = 1.0;
+}
+
+/* rescale the coordinate system r by factor sc >= 0. */
+void trans_rescale(trans_t *r, double sc) {
+  r->bb[0] *= sc;
+  r->bb[1] *= sc;
+  r->orig[0] *= sc;
+  r->orig[1] *= sc;
+  r->x[0] *= sc;
+  r->x[1] *= sc;
+  r->y[0] *= sc;
+  r->y[1] *= sc;
+  r->scalex *= sc;
+  r->scaley *= sc;
+}
+
+/* rescale the coordinate system to size w x h */
+void trans_scale_to_size(trans_t *r, double w, double h) {
+  double xsc = w/r->bb[0];
+  double ysc = h/r->bb[1];
+
+  r->bb[0] = w;
+  r->bb[1] = h;
+  r->orig[0] *= xsc;
+  r->orig[1] *= ysc;
+  r->x[0] *= xsc;
+  r->x[1] *= ysc;
+  r->y[0] *= xsc;
+  r->y[1] *= ysc;
+  r->scalex *= xsc;
+  r->scaley *= ysc;
+  
+  if (w<0) {
+    r->orig[0] -= w;
+    r->bb[0] = -w;
+  }
+  if (h<0) {
+    r->orig[1] -= h;
+    r->bb[1] = -h;
+  }
+}
+
+/* adjust the bounding box to the actual vector outline */
+void trans_tighten(trans_t *r, potrace_path_t *plist) {
+  interval_t i;
+  dpoint_t dir;
+  int j;
+  
+  /* if pathlist is empty, do nothing */
+  if (!plist) {
+    return;
+  }
+
+  for (j=0; j<2; j++) {
+    dir.x = r->x[j];
+    dir.y = r->y[j];
+    path_limits(plist, dir, &i);
+    if (i.min == i.max) {
+      /* make the extent non-zero to avoid later division by zero errors */
+      i.max = i.min+0.5;
+      i.min = i.min-0.5;
+    }
+    r->bb[j] = i.max - i.min;
+    r->orig[j] = -i.min;
+  }
+}
diff --git a/Build/source/libs/potrace/potrace-src/src/trans.h b/Build/source/libs/potrace/potrace-src/src/trans.h
new file mode 100644
index 00000000000..40f37cd2ce5
--- /dev/null
+++ b/Build/source/libs/potrace/potrace-src/src/trans.h
@@ -0,0 +1,36 @@
+/* Copyright (C) 2001-2015 Peter Selinger.
+   This file is part of Potrace. It is free software and it is covered
+   by the GNU General Public License. See the file COPYING for details. */
+
+
+#ifndef TRANS_H
+#define TRANS_H
+
+#include "auxiliary.h"
+
+/* structure to hold a coordinate transformation */
+struct trans_s {
+  double bb[2];    /* dimensions of bounding box */
+  double orig[2];  /* origin relative to bounding box */
+  double x[2];     /* basis vector for the "x" direction */
+  double y[2];     /* basis vector for the "y" direction */
+  double scalex, scaley;  /* redundant info for some backends' benefit */
+};
+typedef struct trans_s trans_t;
+
+/* apply a coordinate transformation to a point */
+static inline dpoint_t trans(dpoint_t p, trans_t t) {
+  dpoint_t res;
+
+  res.x = t.orig[0] + p.x * t.x[0] + p.y * t.y[0];
+  res.y = t.orig[1] + p.x * t.x[1] + p.y * t.y[1];
+  return res;
+}
+
+void trans_rotate(trans_t *r, double alpha);
+void trans_from_rect(trans_t *r, double w, double h);
+void trans_rescale(trans_t *r, double sc);
+void trans_scale_to_size(trans_t *r, double w, double h);
+void trans_tighten(trans_t *r, potrace_path_t *plist);
+
+#endif /* TRANS_H */