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Diffstat (limited to 'Master/xemtex/gslib/impath.ps')
-rw-r--r-- | Master/xemtex/gslib/impath.ps | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/Master/xemtex/gslib/impath.ps b/Master/xemtex/gslib/impath.ps new file mode 100644 index 00000000000..2b7d79fe67f --- /dev/null +++ b/Master/xemtex/gslib/impath.ps @@ -0,0 +1,180 @@ +% Copyright (C) 1992, 1996 Aladdin Enterprises. All rights reserved. +% +% 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., +% 59 Temple Place, Suite 330, Boston, MA, 02111-1307. + +% $Id: impath.ps,v 1.3.4.1.2.1 2003/04/12 14:02:38 giles Exp $ +% impath.ps +% Reverse-rasterize a bitmap to produce a Type 1 outline. +% (This was formerly a Ghostscript operator implemented in C.) + +% <image> <width> <height> <wx> <wy> <ox> <oy> <string> +% type1imagepath <substring> +% Converts an image (bitmap) description of a character into +% a scalable description in Adobe Type 1 format. The +% current transformation matrix should be the same as the +% FontMatrix of the font in which this character will be +% used: this establishes the scaling relationship between +% image pixels (the image is assumed to be 1 unit high in +% user space) and the character coordinate system used in +% the scalable description. wx and wy are the character +% width, and ox and oy are the character origin relative +% to the lower left corner of the bitmap, in *pixels*. +% The image is assumed to be stored in left-to-right, +% top-to-bottom order. Note that this is not consistent +% with the `image' operator's interpretation of the CTM. +% All coordinates in the scalable description are rounded to +% integers, so the coefficients in the FontMatrix should +% be on the order of 1/N for some value of N that is +% either a multiple of the height/width or is large +% compared to the width and height. (There is a +% convention, which some PostScript programs rely on, that +% N=1000.) +% Note that the encoded description has *not* been subjected +% to CharString encryption, which is necessary before the +% description can be given to type1addpath: to do this, +% follow the type1imagepath with +% 4330 exch dup .type1encrypt exch pop +% If the description is too complex to fit into the supplied +% string, a limitcheck error results. A good rule of +% thumb is that the size of the string should be about 6 +% times the number of 1-bits in the image that are not +% completely surrounded by other 1-bits. + +% Import the Type 1 opcodes. +(type1ops.ps) runlibfile + +100 dict +dup /type1imagepath_dict exch def +begin + +/rc { round cvi } bind def +/moving [/rmoveto /hmoveto /vmoveto] def +/drawing [/rlineto /hlineto /vlineto] def + +% Convert the current path to a Type 1 token array. +/putxy % x y ops -> cs_elements + { 3 -1 roll dup x sub rc exch /x exch def + 3 -1 roll dup y sub rc exch /y exch def + % stack: ops dx dy + dup 0 eq + { % dy = 0, use hmoveto/lineto + pop exch 1 get + } + { 1 index 0 eq + { % dx = 0, use vmoveto/lineto + exch pop exch 2 get + } + { % use rmoveto/rlineto + 3 -1 roll 0 get + } + ifelse + } + ifelse + } bind def +/pathtotype1 % -> charstack + { 3 dict begin /x 0 def /y 0 def + mark + { moving putxy + } + { drawing putxy + } + { % Convert curve to relative form + x y 3 + { exch neg 7 index add rc + exch neg 6 index add rc + 8 -2 roll + } + repeat /y exch def /x exch def + 1 index 0 eq 5 index 0 eq and % dy1=dx3=0, hv + { 5 -1 roll pop exch pop /hvcurveto + } + { dup 0 eq 6 index 0 eq and % dx1=dy3=0, vh + { 6 -1 roll pop pop /vhcurveto + } + { /rrcurveto % none of the above + } + ifelse + } + ifelse + } + { /closepath + } + pathforall end + } bind def + +end % type1imagepath_dict + +% The main program +/type1imagepath % image width height wx wy ox oy string -> + % substring + { type1imagepath_dict begin + /tsave save def + /ostring exch def + /oy exch def /ox exch def + /wy exch def /wx exch def + /height exch def /width exch def + /data exch def + + /ofilter ostring /NullEncode filter def + /raster width 7 add 8 idiv def + +% Construct the coordinate transformation. + height dup scale + matrix currentmatrix matrix invertmatrix setmatrix + +% Determine the left side bearing. + /lsbx width + 0 1 width 1 sub + { dup dup 8 idiv 0 exch + raster raster height mul 1 sub + { data exch get or } + for exch 8 mod bitshift 128 and 0 ne + { exch pop exit } + if pop + } + for def + +% Compute and encode the origin, width, and side bearing. + mark + ox oy dtransform + rc /opty exch def rc /optx exch def + wx wy dtransform + rc /iwy exch def rc /iwx exch def + lsbx ox sub 0 dtransform + rc /ilsby exch def rc /ilsbx exch def + ilsbx + iwy 0 ne ilsby 0 ne or + { ilsby iwx iwy /sbw } + { iwx /hsbw } + ifelse + ofilter charstack_write + +% Flip over the Y axis, because the image is stored top-to-bottom. + [1 0 0 -1 0 height] concat +% Account for the character origin. + lsbx oy translate +% Trace the outline. + newpath + width height data .imagepath + gsave matrix setmatrix pathtotype1 grestore + ofilter charstack_write +% Terminate the output + mark /endchar ofilter charstack_write + + ofilter .fileposition ofilter closefile % flush buffers + ostring 0 3 -1 roll getinterval + tsave restore + end + } bind def |