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This is mf2pt1.info, produced by makeinfo version 4.13 from mf2pt1.texi.

INFO-DIR-SECTION TeX
START-INFO-DIR-ENTRY
* mf2pt1::   Produce PostScript Type 1 fonts from Metafont source
END-INFO-DIR-ENTRY

   *mf2pt1*: Produce PostScript Type 1 fonts from Metafont source

   Copyright 2011 Scott Pakin.


File: mf2pt1.info,  Node: Top,  Next: Introduction,  Prev: (dir),  Up: (dir)

mf2pt1
******

`mf2pt1' is a tool that lets font designers design PostScript Type 1
fonts using the Metafont  language.  The same source file can be used
to produce both Type 1 (`.pfb') and bitmap (`.pk') fonts.

* Menu:

* Introduction::                Introduction to mf2pt1
* Usage::                       How to use mf2pt1
* Future Work::                 Features I may one day add to mf2pt1
* Acknowledgments::             People who helped with mf2pt1


File: mf2pt1.info,  Node: Introduction,  Next: Usage,  Prev: Top,  Up: Top

1 Introduction
**************

Metafont  is a high-level, mathematically oriented language for
producing fonts.  The Metafont  interpreter produces device-dependent
bitmaps, which render well at the target resolution on the target
device, but poorly at other resolutions or on other devices.  Adobe's
PostScript Type 1 font format is the de facto font standard for
printers these days.  It is a vector format, which implies that it
scales better than bitmaps, and it delegates the device- and
resolution-dependent tweaking from the font source to the target
device's PostScript renderer.  However, Type 1 fonts are extremely
difficult to code by hand.  Usually, one uses a WYSIWYG program to
design a Type 1 font.  Metafont , with its font-specific programming
language, is an elegant alternative.  A font designer can write
reusable subroutines for repeated features, such as serifs and accents.
He can define a font in terms of arbitrary parameters, such as
"boldness" or "italicness", making it trivial to produce entire
families of fonts from a single source (hence the "meta" in the name
"Metafont ").  Ideally, we would like to design a font using the
Metafont  language, but produce PostScript Type 1 output instead of
bitmaps.

`mf2pt1' helps bridge the gap between Metafont  and Type 1 fonts.
`mf2pt1' facilitates producing PostScript Type 1 fonts from a Metafont
source file.  It is _not_, as the name may imply, an automatic
converter of arbitrary Metafont  fonts to Type 1 format.  `mf2pt1'
imposes a number of restrictions on the Metafont  input.  If these
restrictions are met, `mf2pt1' will produce valid Type 1 output.

* Menu:

* Requirements::                Pre-installation checklist
* Installation::                How to install mf2pt1


File: mf2pt1.info,  Node: Requirements,  Next: Installation,  Prev: Introduction,  Up: Introduction

1.1 Requirements
================

Before using `mf2pt1', you will need to install the following programs:

Perl
     `mf2pt1' is written in Perl.  You will need a Perl interpreter to
     run it.

MetaPost
     `mf2pt1' actually uses MetaPost, not Metafont , to produce
     PostScript output.  Specifically, you will need the `mpost'
     executable and the `mfplain.mp' base file.

Type 1 Utilities
     Producing properly encoded Type 1 fonts is tricky.  `mf2pt1'
     delegates the effort to the Type 1 Utilities, specifically, to the
     `t1asm' program within that suite.

FontForge (optional)
     FontForge is a WYSIWYG, but scriptable, Type 1 font-editing
     program.  Although FontForge is not strictly required for `mf2pt1'
     to produce a Type 1 font, `mf2pt1' uses FontForge when available
     to autohint the generated Type 1 font, thereby making it look
     better especially at lower resolutions.

   Perl is available from the Comprehensive Perl Archive Network
(http://www.cpan.org); MetaPost and the Type 1 utilities are available
from the Comprehensive TeX Archive Network (http://www.ctan.org); and,
FontForge is available from `http://fontforge.sourceforge.net/'.  In
addition, MetaPost's home page is
`http://cm.bell-labs.com/who/hobby/MetaPost.html', and the Type 1
utilities' home page is `http://www.lcdf.org/type/'.

   Besides being useful for autohinting fonts, FontForge enables a font
designer to hint fonts manually for additional fine-tuning and to
convert among a variety of font formats, such as PostScript, TrueType,
and X Window fonts.  FontForge is strongly recommended as a complement
to `mf2pt1'.


File: mf2pt1.info,  Node: Installation,  Prev: Requirements,  Up: Introduction

1.2 Installation
================

To install `mf2pt1', move the `mf2pt1' executable someplace where your
operating system can find it.  If you're running Microsoft Windows, you
should rename the program to `mf2pt1.pl', so that Windows knows it's a
Perl script.  (Alternatively, if you have `pl2bat', use that to produce
a `mf2pt1.bat' file, which you can run as simply `mf2pt1'.)

   The next step is to produce a `mf2pt1.mem' file from the supplied
`mf2pt1.mp'.  The command to do this differs from system to system but
is usually something like the following:

     mpost -progname=mpost -ini mf2pt1 \\dump

   Move the resulting `mf2pt1.mem' file someplace where MetaPost can
find it.


   The `mf2pt1' documentation (what you're reading now) is written in
Texinfo and can therefore easily be converted to a variety of formats:

PDF (`mf2pt1.pdf')
          texi2pdf mf2pt1.texi

PostScript (`mf2pt1.ps')
          texi2dvi mf2pt1.texi
          dvips mf2pt1.dvi -o mf2pt1.ps

HTML (`mf2pt1.html')
          makeinfo --html mf2pt1.texi

Info (`mf2pt1.info')
          makeinfo mf2pt1.texi

N.B.  The `install-info' command is a convenient way to install
`mf2pt1.info' on your system.


   On Unix, you may also want to generate an `mf2pt1' man page.  The
man page is embedded within the `mf2pt1' Perl script and can be
extracted with `pod2man':

     pod2man --center="User Commands" --date="2 August 2011" \
       --release="v2.4.5" mf2pt1 > mf2pt1.1

You can then move `mf2pt1.1' into `/usr/man/man1' or any other man page
directory.  Note that the `mf2pt1' man page is fairly rudimentary.  It
is primarily a list of the command-line options (*note Font
information::) and a pointer to the document that you're reading now.


File: mf2pt1.info,  Node: Usage,  Next: Future Work,  Prev: Introduction,  Up: Top

2 Usage
*******

`mf2pt1' is fairly straightforward to use.  To process a Metafont
source file, merely specify the filename:

     mf2pt1 myfont.mf

That simple command automatically performs all of the following
operations:

  1. Read `myfont.mf'.

  2. Use `mpost' to convert each character to a separate Encapsulated
     PostScript (EPS) file named `myfont.NUM'.

  3. Process and merge the EPS files into a single "disassembled"
     Type 1 font called `myfont.pt1'.

  4. Run `t1asm' from the Type 1 Utilities to convert the disassembled
     font into a true, binary Type 1 font called `myfont.pfb'.

  5. Invoke `fontforge' to apply rendering hints to `myfont.pfb' and to
     attempt to remove overlapping paths.

   The external programs launched by `mf2pt1'--`mpost', `t1asm', and
`fontforge'--can be overridden by setting the eponymous, uppercase
environment variable.  For example, invoking FontForge's predecessor,
PfaEdit, instead of FontForge is simply a matter of setting the
`FONTFORGE' environment variable to `pfaedit' before invoking `mf2pt1'.
As a corollary, you can inhibit an `mf2pt1' external program from
running by setting the corresponding environment variable to the name
of a nonexistent program.

* Menu:

* Restrictions::                Restrictions imposed on the font source code
* Font information::            Specifying PostScript font characteristics
* Additional command-line options::  Options unrelated to font characteristics
* Custom font encodings::       Altering the mapping from character name to number
* Restoring mfplain defaults::  Using the original (un)filldraw and pencircle


File: mf2pt1.info,  Node: Restrictions,  Next: Font information,  Prev: Usage,  Up: Usage

2.1 Restrictions
================

If `mf2pt1' sounds too good to be true, it is--somewhat.  `mf2pt1' is
not a general-purpose Metafont -to-Type 1 converter.  Rather, it can
convert only certain Metafont  constructs.  This is not a showstopper
for new fonts designed with `mf2pt1' in mind, but it is unlikely that
`mf2pt1' will work on an arbitrary Metafont  source file.

   `mf2pt1''s biggest restriction is that each glyph must be drawn
entirely from closed paths, using Metafont 's *fill* and *unfill*
commands.  (`mf2pt1' has limited support for *draw* and *undraw*, but
their use is currently discouraged.  *filldraw* and *unfilldraw* issue a
warning message and invoke *draw* and *undraw*, respectively.)  The
Type 1 format requires that these paths be nonoverlapping.  The
following are some of the alternatives for removing path overlaps:

  1. Install FontForge.  As part of its final step in producing a
     Type 1 font, `mf2pt1' instructs FontForge to replace overlapping
     paths with nonoverlapping paths.

  2. Remove overlaps using Metafont  code within the font program
     itself.  A `.zip' file attachment to a 6 January 2005 article
     (http://tug.org/mailman/htdig/metapost/2005-January/000080.html) by
     Boguslaw Jackowski on the MetaPost mailing list (subject: "Re: all
     intersections between two paths") includes a MetaPost library which
     assists with that task.  The library provides a *find_outlines*
     command which can be used to define a path as the union of two
     other paths.  A number of MetaPost example programs are also
     included in the `.zip' file.

  3. Design your fonts from the beginning without using overlapping
     paths.

   A secondary restriction is that `mf2pt1' redefines a number of Plain
Metafont  commands, such as *beginchar*, *fill*, and *unfill*.  Metafont
font programs which redefine or bypass these (using Metafont
primitives) will not be convertible with `mf2pt1'.

   A far less severe restriction is due to `mf2pt1''s utilizing
MetaPost's Metafont  interface instead of Metafont  itself.  The
implication is that commands not defined by MetaPost's `mfplain.mp'
cannot be handled by `mf2pt1', either.  Very few fonts will have a
problem with this restriction but see the MetaPost manual for more
information.


File: mf2pt1.info,  Node: Font information,  Next: Additional command-line options,  Prev: Restrictions,  Up: Usage

2.2 Specifying font information
===============================

Metafont  fonts normally specify a set of *fontdimen*s which provide
information about a particular font that cannot otherwise be inferred.
These include features such as the font's x-height, quad width,
interword stretchability and shrinkability, and other design
characteristics that TeX makes use of.  PostScript fonts utilize a
largely different set of font parameters, such as the underline
position and thickness, font family name, and copyright notice.
`mf2pt1' provides Metafont  commands to define the PostScript font
parameters in the generated Type 1 font.  These parameters should
appear in the Metafont  source file as follows:

     if known ps_output:
       ...
     fi

`ps_output' is defined by `mf2pt1' but not by Plain Metafont .
Checking if it is known is the recommended way to determine if the font
is being built under `mf2pt1'.

* Menu:

* Parameters::                  Font-information commands available to Metafont
* Command-line equivalents::    Specifying font features on the command line
* Default values::              Types and default values of each parameter
* Parameter example::           Metafont example which specifies all parameters


File: mf2pt1.info,  Node: Parameters,  Next: Command-line equivalents,  Prev: Font information,  Up: Font information

2.2.1 Parameters
----------------

   The following list presents all of the font-information commands
provided by `mf2pt1' and describes what each command means.  Commands
marked with an asterisk are also defined by Plain Metafont  and
therefore do not need to be enveloped within a test for `ps_output'.

*font_coding_scheme*
     The mapping between character numbers and PostScript names.  If
     this is the name of a file, `mf2pt1' expects it to contain
     PostScript code defining a font-encoding vector.  *Note Custom
     font encodings::, for an example of such a file.  If
     *font_coding_scheme* is not the name of a file, `mf2pt1' expects
     it to be one of the literal strings `standard' (Adobe standard
     encoding), `isolatin1' (ISO Latin 1 encoding), `ot1' (TeX 7-bit
     encoding), `t1' (TeX 8-bit encoding), or `asis' (encoding
     integrated with the character programs using the *glyph_name*
     command as described in *note Custom font encodings::).  Anything
     else will generate a warning message and cause `mf2pt1' to use
     `standard' instead.

*font_comment*
     A textual comment that will appear within the generated font.
     This is often used for copyright notices.

*font_family*
     The family that this font belongs to.  For example, "Utopia Bold
     Italic" belongs to the `Utopia' family.

*font_fixed_pitch*
     Whether the font is monospaced (if *true*) or or proportionally
     spaced (if *false*).

*font_identifier (*)*
     The full name of the font, e.g., `Utopia Bold Italic'.

*font_name*
     The symbolic font name, used to load the font from a PostScript
     document.  Spaces are forbidden.  Generally, the font name is of
     the form `FAMILY-MODIFIERS'.  For example, the font name of Utopia
     Bold Italic would be `Utopia-BoldItalic'.

*font_size (*)*
     The font design size.  This is specified in "sharped" units within
     Metafont  code or as a point size on the command line.

*font_slant (*)*
     When specified with *font_slant*, the amount of slant per point.
     When specified with `--italicangle', the angle in counterclockwise
     degrees from the vertical (i.e., zero for an upright font,
     negative for a right-slanting italic font).

*font_underline_position*
     The vertical position at which an underline should lie, specified
     in "sharped" units within Metafont  code or as a number of points
     on the command line.

*font_underline_thickness*
     The thickness of an underline, specified in "sharped" units within
     Metafont  code or as a number of points on the command line.

*font_unique_id*
     The unique ID for this font.  The ID should be between 0 and
     16,777,215.  If not specified, `mf2pt1' will choose an ID at
     random from the "open" range, 4,000,000-4,999,999.  All IDs not in
     that range are allocated by contacting Adobe's UniqueID
     Coordinator.  (I don't believe a fee is involved, but I don't know
     for sure.)

*font_version*
     The version number of the font.  This should be of the form
     `MMM.MMM', where MMM is the major version number and MMM is the
     minor version number.

*font_weight*
     The font weight.  For example, the font weight of Utopia Bold
     Italic is `Bold'.


File: mf2pt1.info,  Node: Command-line equivalents,  Next: Default values,  Prev: Parameters,  Up: Font information

2.2.2 Command-line equivalents
------------------------------

   Each of the font-information commands listed in *note Parameters::
has a command-line equivalent.  Their use is discouraged but they are
listed here for completeness:

*font_coding_scheme*         `--encoding'
*font_comment*               `--comment'
*font_family*                `--family'
*font_fixed_pitch*           `--fixedpitch'
*font_identifier*            `--fullname'
*font_name*                  `--name'
*font_size*                  `--designsize'
*font_slant*                 `--italicangle'
*font_underline_position*    `--underpos'
*font_underline_thickness*   `--underthick'
*font_unique_id*             `--uniqueid'
*font_version*               `--fontversion'
*font_weight*                `--weight'

   A special case is `--fixedpitch' which does not take an argument.
Rather, you should use `--fixedpitch' as the equivalent of
`font_fixed_pitch true' and `--nofixedpitch' as the equivalent of
`font_fixed_pitch false'.


File: mf2pt1.info,  Node: Default values,  Next: Parameter example,  Prev: Command-line equivalents,  Up: Font information

2.2.3 Default values
--------------------

   The next table lists the Metafont  type and default value of each of
the parameters listed in *note Parameters::.

*font_coding_scheme*         *string*    `"standard"'
*font_comment*               *string*    `"Font converted to Type 1
                                         by mf2pt1, written by
                                         Scott Pakin."'
*font_family*                *string*    (The value of
                                         *font_identifier*)
*font_fixed_pitch*           *boolean*   *false*
*font_identifier*            *string*    (The input filename, minus
                                         `.mf')
*font_name*                  *string*    (The value of
                                         *font_family*, plus an
                                         underscore, plus the
                                         value of *font_weight*,
                                         with all spaces removed)
*font_size*                  *numeric*   (Must be specified or
                                         `mf2pt1' will abort with
                                         an error message)
*font_slant*                 *numeric*   0
*font_underline_position*    *numeric*   -1
*font_underline_thickness*   *numeric*   0.5
*font_unique_id*             *string*    (Randomly generated in the
                                         range 4000000-4999999)
*font_version*               *string*    `"001.000"'
*font_weight*                *string*    `"Medium"'



File: mf2pt1.info,  Node: Parameter example,  Prev: Default values,  Up: Font information

2.2.4 Parameter example
-----------------------

   As an example, the following Metafont  code shows the usage of all
of the parameters that `mf2pt1' accepts:

if known ps_output:
     font_coding_scheme         "ot1";
     font_comment               "Copyright (C) 2011 Scott Pakin.";
     font_family                "Kerplotz";
     font_fixed_pitch           false;
     font_identifier            "Kerplotz Light Oblique";
     font_name                  "Kerplotz-LightOblique";
     font_size                  10pt#;      % Important to include
                                this.
     font_slant                 1/6;
     font_underline_position    -1pt#;
     font_underline_thickness   1/2pt#;
     font_unique_id             "4112233";      % Better to omit
                                this.
     font_version               "002.005";
     font_weight                "Light";
   fi

In the above, the *font_fixed_pitch* call could have been omitted, as
it defaults to *false*.  Also, unless you've requested a unique ID from
Adobe, it's generally better not to assign *font_unique_id*; let
`mf2pt1' choose a random value itself.

   The same parameters can also be specified on the command line as
follows:

     mf2pt1 --encoding=ot1 --comment="Copyright (C) 2011 Scott Pakin."
       --family=Kerplotz --nofixedpitch --fullname="Kerplotz Light Oblique"
       --name=Kerplotz-LightOblique --designsize=10 --italicangle=-9.5
       --underpos=-100 --underthick=50 --uniqueid=4112233 --version=002.005
       --weight=Light kerplotz.mf

Note that a Metafont  font slant of 1/6 is equal to a PostScript italic
angle of approximately -9.5.  The conversion formula is slant =
-tan(angle).  In addition, the underline position and thickness must be
multiplied by 1000/*font_size* to convert from the Metafont  units that
are used within the `.mf' file to the PostScript units that are used on
the command line.


File: mf2pt1.info,  Node: Additional command-line options,  Next: Custom font encodings,  Prev: Font information,  Up: Usage

2.3 Additional command-line options
===================================

In addition to the command-line options for setting font parameters
that were presented in *note Parameters::, `mf2pt1' supports a
`--rounding' option.  While `mf2pt1' normally rounds all font
coordinates to the nearest integer, `--rounding' increases coordinate
precision by instructing `mf2pt1' to round instead to the nearest
multiple of a given fractional number.  For example, `--rounding=0.25'
rounds the coordinate (7.4, 10.3) to (7.5, 10.25) while it would
otherwise be rounded to the less-precise (7, 10).

   Large glyphs can be problematic in MetaPost and therefore in
`mf2pt1'.  Unlike Metafont , MetaPost does not honor `mag' for
magnifying dimensions.  Rather, the number of PostScript (a.k.a. "big")
points per pixel--`bpppix'--is hardwired to 0.02 and all other
dimensions (`mm', `in', `pt', etc.) are expressed in terms of that.
Consequently, glyphs that multiply a large number of font units by a
dimension are likely to exceed 4096, the largest value that MetaPost
can represent in its fixed-point format.  If numerical overflow becomes
a problem you can use the `--bpppix' option to `mf2pt1' to change the
value of `bpppix'.  For example, specifying `--bpppix=0.2' enables a
tenfold increase in maximum glyph size (with a corresponding decrease
in precision).

   After generating a Type 1 font, `mf2pt1' runs it through FontForge
to add hinting information, remove overlaps, and otherwise clean up the
generated font.  The `--ffscript' option specifies the filename of a
FontForge script to use instead of the default script, which is listed
below:

     Open($1);
     SelectAll();
     RemoveOverlap();
     AddExtrema();
     Simplify(0, 2);
     CorrectDirection();
     Simplify(0, 2);
     RoundToInt();
     AutoHint();
     Generate($1);
     Quit(0);

See the FontForge documentation for an explanation of each of those
commands and a description of other commands made available to
FontForge scripts.  `mf2pt1' runs the script with one argument (`$1'),
which is the name of the generated `.pfb' file.

   `mf2pt1' also supports a `--help' option which summarizes all of the
program's command-line options.


File: mf2pt1.info,  Node: Custom font encodings,  Next: Restoring mfplain defaults,  Prev: Additional command-line options,  Up: Usage

2.4 Custom font encodings
=========================

*note Parameters::, lists the font encodings currently supported by
`mf2pt1' and mentions that an alternate encoding can be specified by
providing the name of an encoding file.  To elaborate, the following
example represents the contents of an encoding file which defines
a--largely useless nowadays--EBCDIC font encoding:

     `% Sample encoding vector: EBCDIC
     % The encoding vector must have a name and be defined as a
     PostScript array.
     /ebcdic_encoding [
     /_a0 /_a1 /_a2 /_a3 /_a4 /_a5 /_a6 /_a7 /_a8 /_a9 /_a10 /_a11 /_a12
     /_a13 /_a14 /_a15 /_a16 /_a17 /_a18 /_a19 /_a20 /_a21 /_a22 /_a23
     /_a24 /_a25 /_a26 /_a27 /_a28 /_a29 /_a30 /_a31 /_a32 /_a33 /_a34
     /_a35 /_a36 /_a37 /_a38 /_a39 /_a40 /_a41 /_a42 /_a43 /_a44 /_a45
     /_a46 /_a47 /_a48 /_a49 /_a50 /_a51 /_a52 /_a53 /_a54 /_a55 /_a56
     /_a57 /_a58 /_a59 /_a60 /_a61 /_a62 /_a63 /space /_a65 /_a66 /_a67
     /_a68 /_a69 /_a70 /_a71 /_a72 /_a73 /bracketleft /period /less
     /parenleft /plus /exclam /ampersand /_a81 /_a82 /_a83 /_a84 /_a85
     /_a86 /_a87 /_a88 /_a89 /bracketright /dollar /asterisk /parenright
     /semicolon /asciicircum /hyphen /slash /_a98 /_a99 /_a100 /_a101
     /_a102 /_a103 /_a104 /_a105 /bar /comma /percent /underscore
     /greater /question /_a112 /_a113 /_a114 /_a115 /_a116 /_a117
     /_a118 /_a119 /_a120 /_a121 /colon /numbersign /at /quoteright
     /equal /quotedbl /_a128 /a /b /c /d /e /f /g /h /i /_a138 /_a139
     /_a140 /_a141 /_a142 /_a143 /_a144 /j /k /l /m /n /o /p /q /r
     /_a154 /_a155 /_a156 /_a157 /_a158 /_a159 /_a160 /asciitilde /s /t
     /u /v /w /x /y /z /_a170 /_a171 /_a172 /_a173 /_a174 /_a175 /_a176
     /_a177 /_a178 /_a179 /_a180 /_a181 /_a182 /_a183 /_a184 /quoteleft
     /_a186 /_a187 /_a188 /_a189 /_a190 /_a191 /braceleft /A /B /C /D
     /E /F /G /H /I /_a202 /_a203 /_a204 /_a205 /_a206 /_a207
     /braceright /J /K /L /M /N /O /P /Q /R /_a218 /_a219 /_a220 /_a221
     /_a222 /_a223 /backslash /_a225 /S /T /U /V /W /X /Y /Z /_a234
     /_a235 /_a236 /_a237 /_a238 /_a239 /zero /one /two /three /four
     /five /six /seven /eight /nine /_a250 /_a251 /_a252 /_a253 /_a254
     /_a255
     % Don't forget to end the array.
     ] def'

All entries in the encoding vector are PostScript "names" and therefore
must be prefixed with a slash.  Unnamed characters such as control
characters are commonly named `_aNUMBER', where NUMBER is the decimal
offset into the character table.  Undefined characters are indicated by
`.notdef'.  In the EBCDIC example, the character at position 0 in the
font will be named `a0'; the character at position 1 will be named
`a1'; the character at position 74 will be named `bracketleft'; the
character at position 129 will be named `a'; and so forth.

   Individual characters can be mapped to an encoding either numerically
or by executing a *glyph_name* command within a character definition.
For example, the following code overrides the character position passed
to *beginchar* (i.e., 123) with whatever character position the current
encoding has designated for the `ohungarumlaut' glyph:

     beginchar (123, cap_height#-1/2pt#, cap_height#, 0);
       if known ps_output:
         glyph_name "ohungarumlaut";
       fi
       ...
     endchar;


File: mf2pt1.info,  Node: Restoring mfplain defaults,  Prev: Custom font encodings,  Up: Usage

2.5 Restoring `mfplain' defaults
================================

`mf2pt1' normally redefines *filldraw* as *fill* and *unfilldraw* and
*unfill* because Type 1 fonts don't allow overlapping curves.
Similarly, `mf2pt1' redefines *pencircle* as a 20-gon to coerce
MetaPost into drawing it using a filled instead of a stroked PostScript
path.

   If you know you'll be postprocessing your fonts using FontForge,
which can automatically convert overlapping paths to nonoverlapping
paths, then you can restore the original `mfplain.mp' definitions of
*filldraw*, *unfilldraw*, and *pencircle* as follows:

     if known ps_output:
       pencircle := mfplain_pencircle;
       let filldraw := mfplain_filldraw;
       let unfilldraw := mfplain_unfilldraw;
     fi


File: mf2pt1.info,  Node: Future Work,  Next: Acknowledgments,  Prev: Usage,  Up: Top

3 Future Work
*************

One avenue for future work is to enable the font designer to specify
Type 1 font hints directly in the Metafont  font program.  Hinting is a
way for a font designer to specify how a font should be rendered at low
resolutions, for example, at typical monitor resolutions.  In Metafont
, this is done by controlling the way that points are mapped to pixel
locations, using commands such as *define_corrected_pixels*,
*define_blacker_pixels*, and *lowres_fix*.  Type 1 fonts are hinted in
a completely different manner.  Type 1 hints distinguish key character
features, such as stems and dots, from decorations which can be
discarded at low resolutions.  The PostScript interpreter uses that
information to determine how to map points to pixels.  Although
`mf2pt1' employs FontForge to autohint the fonts it generates, the
approach is mechanical and unlikely to hint as well as a human can do
manually.  It would be convenient for `mf2pt1' one day to provide
Metafont  commands for *hstem*, *vstem*, *dotsection*, and the other
Type 1 hints.  That way, hints will no longer need to be re-added
manually every time `mf2pt1' regenerates a Type 1 font.

   Another future addition to `mf2pt1' is the addition of more font
encodings.  The following are the encodings that `mf2pt1' will most
likely accept:

`TeXMathItalicEncoding'
     Upper- and lowercase Greek and Latin letters, old-style digits,
     and a few symbols and accents.

`TeXMathSymbolEncoding'
     A variety of symbols, as well as calligraphic Latin majuscules.

`TeXMathExtensionEncoding'
     Variable-sized symbols, such as braces, integrals, and radicals.

`AdobeExpert'
     Small caps, currency symbols, old-style digits, and various
     superior and inferior letters and digits.


File: mf2pt1.info,  Node: Acknowledgments,  Prev: Future Work,  Up: Top

Acknowledgments
***************

Many thanks are owed to Werner Lemberg for writing the code underlying
the `--rounding' option; for introducing the *glyph_name* command and
`asis' encoding vector; for providing the default FontForge script
listed in *note Additional command-line options::; for fixing some
code-generation bugs in `mf2pt1'; for finding a more robust way to dump
`mf2pt1.mem'; for directing me to the overlap-removal code mentioned in
*note Restrictions::; for supplying the _crossproduct_, _makeline_, and
_is_clockwise_ functions used by `mf2pt1.mp'; for proposing the
`--bpppix' command-line option; and, for suggesting various features and
improvements to `mf2pt1'.  Thanks also go to Werner Lemberg and Boguslaw
Jackowski for updating the *is_clockwise* function in `mf2pt1.mp' to
work around a bug in MetaPost which relates to the *turningnumber*
command.  Finally, thanks go to Ralf Stubner for providing the T1
encoding vector and for pointing out a typo in the generated font
programs; and, to Michael Zedler for alerting me to problems with
`--encoding' and suggesting I modify that option to accept PostScript
`.enc' files.



Tag Table:
Node: Top301
Node: Introduction840
Node: Requirements2677
Node: Installation4426
Node: Usage6240
Node: Restrictions7956
Node: Font information10346
Node: Parameters11706
Node: Command-line equivalents15081
Node: Default values16205
Node: Parameter example17883
Node: Additional command-line options19902
Node: Custom font encodings22241
Node: Restoring mfplain defaults25692
Node: Future Work26551
Node: Acknowledgments28418

End Tag Table