or
ttf2pt1 [-options] ttffont.ttf -
The versions 3.0 and later got rather extensive post-processing algorithm that brings the converted fonts to the requirements of the Type1 standard, tries to correct the rounding errors introduced during conversions and some simple kinds of bugs that are typical for the public domain TTF fonts. It also generates the hints that enable much better rendering of fonts in small sizes that are typical for the computer displays. But everything has its price, and some of the optimizations may not work well for certain fonts. That's why the options were added to the converter, to control the performed optimizations.
Most of the time no options are neccessary (with a possible exception
of `-e'). But if there are some troubles with the resulting font, they
may be used to control the conversion.
The options are:
a - Print out the absolute coordinates of dots in outlines. Such a font can not be used by any program (that's why this option is incompatible with `-e') but it has proven to be a valuable debuging information.
r - Do not reverse the direction of outlines. The TTF fonts have
the standard direction of outlines opposite to the Type1 fonts. So
they should be reversed during proper conversion. This option
may be used for debugging or to handle a TTF font with wrong
direction of outlines (possibly, converted in a broken way from
a Type1 font). The first signs of the wrong direction are the
letters like ``P'' or ``B'' without the unpainted ``holes'' inside.
[ S.B.: Personally I don't think that this option is particularly useful.
The same result may be achieved by piping the unassembled data
through t1asm, the Type 1 assembler. And, anyways, it's good to
have the t1utils package handy. But Mark and many users think that
this functionality is good and it took not much time to add this option. ]
f/F - The font file. Depending on the other options this file will have one of the suffixes .t1a, .pfa or .pfb. If the conversion result is requested on the standard output ('-' is used as the output file name) then the font file will also be written there by default, if not overwritten by another suboption of -G. Default: enabled
a/A - The Adobe font metrics file (.afm). Default: enabled
e/E - The dvips encoding file (.enc).
Default: disabled
After the plus sign an optional argument for the language extractor may be specified. The format of the argument is absolutely up to the particular language converter. The primary purpose of the argument is to support selection of planes for the multi-plane Eastern encodings but it can also be used in any other way. The language extractor may decide to add the plane name in some form to the name of the resulting font. None of the currently supported languages make any use of the argument yet.
As of now the following languages are supported:
latin1 - for all the languages using the Latin-1 encoding
latin2 - for the Central European languages
latin4 - for the Baltic languages
latin5 - for the Turkish language
cyrillic - for the languages with Cyrillic alphabet
russian - historic synonym for cyrillic
bulgarian - historic synonym for cyrillic
adobestd - for the AdobeStandard encoding used by TeX
plane+argument - to select one plane from a multi-byte encoding
The argument of the ``plane'' language may be in one of three forms:
plane+pid=<pid>,eid=<eid>
plane+pid=<pid>,eid=<eid>,<plane_number>
plane+<plane_number>
Pid (TTF platform id) and eid (TTF encoding id) select a particular TTF encoding table in the original font. They are specified as decimal numbers. If this particular encoding table is not present in the font file then the conversion fails. The native ("ttf") front-end parser supports only pid=3 (Windows platform), the FreeType-based ("ft") front-end supports any platform. If pid/eid is not specified then the TTF encoding table is determined as usual: Unicode encoding if it's first or an 8-bit encoding if not (and for an 8-bit encoding the plane number is silently ignored). To prevent the converter from falling back to an 8-bit encoding, specify the Unicode pid/eid value explicitly.
Plane_number is a hexadecimal (if starts with ``0x") or decimal number. It gives the values of upper bytes for which 256 characters will be selected. If not specified, defaults to 0. It is also used as a font name suffix (the leading ``0x'' is not included into the suffix).
NOTE: You may notice that the language names are not uniform: some are the names of particular languages and some are names of encodings. This is because of the different approaches. The original idea was to implement a conversion from Unicode to the appropriate Windows encoding for a given language. And then use the translation tables to generate the fonts in whatever final encodings are needed. This would allow to pile together the Unicode fonts and the non-Unicode Windows fonts for that language and let the program to sort them out automatically. And then generate fonts in all the possible encodings for that language. An example of this approach is the Russian language support. But if there is no multiplicity of encodings used for some languages and if the non-Unicode fonts are not considered important by the users, another way would be simpler to implement: just provide only one table for extraction of the target encoding from Unicode and don't bother with the translation tables. The latin* ``languages'' are examples of this approach. If somebody feels that he needs the Type1 fonts both in Latin-* and Windows encodings he or she is absolutely welcome to submit the code to implement it.
WARNING:
Some of the glyphs included into the AdobeStandard encoding are not
included into the Unicode standard. The most typical examples of such
glyphs are ligatures like `fi', `fl' etc. Because of this the font
designers may place them at various places. The converter tries to
do its best, if the glyphs have honest Adobe names and/or are
placed at the same codes as in the Microsoft fonts they will be
picked up. Otherwise a possible solution is to use the option `-L'
with an external map.
Likewise to `-l', an argument may be specified after the map file name. But in this case the argument has fixed meaning: it selects the original TTF encoding table (the syntax is the same as in `-l plane') and/or a plane of the map file. The plane name also gets added after dash to the font name. The plane is a concept used in the Eastern fonts with big number of glyphs: one TTF font gets divided into multiple Type1 fonts, each containing one plane of up to 256 glyphs. But with a little creativity this concept may be used for other purposes of combining multiple translation maps into one file. To extract multiple planes from a TTF font ttf2pt1 must be run multiple times, each time with a different plane name specified.
The default original TTF encoding table used for the option `-L' is
Unicode. The map files may include directives to specify different original
TTF encodings. However if the pid/eid pair is specified with
it overrides any original encoding specified in the map file.
h - the maximal hint stack depth for the substituted hints.
The default value is 128, according to the limitation in X11. This seems to
be the lowest (and thus the safest) widespread value. To display the
hint stack depth required by each glyph in a .t1a file use the script
scripts/cntstems.pl.
b/B - Guessing of the ForceBold parameter. This parameter helps the Type1 engine to rasterize the bold fonts properly at small sizes. But the algorithm used to guess the proper value of this flag makes that guess based solely on the font name. In rare cases that may cause errors, in these cases you may want to disable this guessing. Default: enabled
h/H - Autogeneration of hints. The really complex outlines may confuse the algorithm, so theoretically it may be useful sometimes to disable them. Although up to now it seems that even bad hints are better than no hints at all. Default: enabled
u/U - Hint substitution. Hint substitution is a technique permitting generation of more detailed hints for the rasterizer. It allows to use different sets of hints for different parts of a glyph and change these sets as neccessary during rasterization (that's why ``substituted"). So it should improve the quality of the fonts rendered at small sizes. But there are two catches: First, the X11 library has rather low limit for the font size. More detailed hints increase the file size and thus increase the chance of hitting this limit (that does not mean that you shall hit it but you may if your fonts are particularly big). This is especially probable for Unicode fonts converted with option `-a', so you may want to use `-a' together with `-Ou'. See app/X11/README for the description of a patch to X11 which fixes this problem. Second, some rasterizers (again, X11 is the typical example) have a limitation for total number of hints used when drawing a glyph (also known as the hint stack depth). If that stack overflows the glyph is ignored. Starting from version 3.22 ttf2pt1 uses algorithms to minimizing this depth, with the trade-off of slightly bigger font files. The glyphs which still exceed the limit set by option '-mh' have all the substituted hints removed and only base hints left. The algorithms seem to have been refined far enough to make the fonts with substituted hints look better than the fonts without them or at least the same. Still if the original fonts are not well-designed the detailed hinting may emphasize the defects of the design, such as non-even thickness of lines. So provided that you are not afraid of the X11 bug the best idea would be to generate a font with this feature and without it, then compare the results using the program other/cmpf (see the description in other/README) and decide which one looks better. Default: enabled
o/O - Space optimization of the outlines' code. This kind of optimization never hurts, and the only reason to disable this feature is for comparison of the generated fonts with the fonts generated by the previous versions of converter. Well, it _almost_ never hurts. As it turned out there exist some brain-damaged printers which don't understand it. Actually this feature does not change the outlines at all. The Type 1 font manual provides a set of redundant operators that make font description shorter, such as `10 hlineto' instead of `0 10 rlineto' to describe a horizontal line. This feature enables use of these operators. Default: enabled
s/S - Smoothing of outlines. If the font is broken in some way (even the ones that are not easily noticeable), such smoothing may break it further. So disabling this feature is the first thing to be tried if some font looks odd. But with smoothing off the hint generation algorithms may not work properly too. Default: enabled
t/T - Auto-scaling to the 1000x1000 Type1 standard matrix. The TTF fonts are described in terms of an arbitrary matrix up to 4000x4000. The converted fonts must be scaled to conform to the Type1 standard. But the scaling introduces additional rounding errors, so it may be curious sometimes to look at the font in its original scale. Default: enabled
v/V - Do vectorization on the bitmap fonts. Functionally ``vectorization'' is the same thing as ``autotracing'', a different word is used purely to differentiate it from the Autotrace library. It tries to produce nice smooth outlines from bitmaps. This feature is still a work in progress though the results are already mostly decent. Default: disabled
w/W - Glyphs' width corection. This option is designed to be used on broken fonts which specify too narrow widths for the letters. You can tell that a font can benefit from this option if you see that the characters are smashed together without any whitespace between them. This option causes the converter to set the character widths to the actual width of this character plus the width of a typical vertical stem. But on the other hand the well-designed fonts may have characters that look better if their widths are set slightly narrower. Such well-designed fonts will benefit from disabling this feature. You may want to convert a font with and without this feature, compare the results and select the better one. This feature may be used only on proportional fonts, it has no effect on the fixed-width fonts. Default: disabled
z/Z - Use the Autotrace library on the bitmap fonts. The results
are horrible and the use of this option is not recommended. This option is
present for experimental purposes. It may change or be removed in the
future. The working tracing can be achieved with option -OV.
Default: disabled
ttf - built-in parser for the ttf files (suffix .ttf)
bdf - built-in parser for the BDF files (suffix .bdf)
ft - parser based on the FreeType-2 library (suffixes .ttf, .otf, .pfa, .pfb)
The parser ft is NOT linked in by default. See Makefile for instructions how to enable it. We do no support this parser on Windows: probably it will work but nobody tried and nobody knows how to build it.
The conversion of the bitmap fonts (such as BDF) is simplistic yet,
producing jagged outlines. When converting such fonts, it might be
a good idea to turn off the hint substitution (using option -Ou)
because the hints produced will be huge but not adding much to the
quality of the fonts.
cat *.pf[ab] | grep UniqueID | sort | uniq -c | grep -v ' 1 '
Or if you use scripts/convert it will do that for you automatically
plus it will also give the exact list of files with duplicate UIDs.
The algorithm that implemented the forced fixed width had major flaws, so it was disabled. The code is still in the program and some day it will be refined and returned back. Meanwhile the option name `-f' was reused for another option. The old version was:
-f - Don't try to force the fixed width of font. Normally the converter considers the fonts in which the glyph width deviates by not more than 5% as buggy fixed width fonts and forces them to have really fixed width. If this is undesirable, it can be disabled by this option.
The .pfa font format supposes that the description of the characters is binary encoded and encrypted. This converter does not encode or encrypt the data by default, you have to specify the option `-e' or use the t1asm program to assemble (that means, encode and encrypt) the font program. The t1asm program that is included with the converter is actually a part of the t1utils package, rather old version of which may be obtained from
http://ttf2pt1.sourceforge.net/t1utils.tar.gz
Note that t1asm from the old version of that package won't work properly with the files generated by ttf2pt1 version 3.20 and later. Please use t1asm packaged with ttf2pt1 or from the new version t1utils instead. For a newer version of t1utils please look at
http://www.lcdf.org/~eddietwo/type/
ttf2pt1 -e ttffont.ttf t1font
ttf2pt1 ttffont.ttf - | t1asm >t1font.pfa
represent two ways to get a working font. The benefit of the second form is that other filters may be applied to the font between the converter and assembler.
The mailing list with announcements about ttf2pt1. It is a moderated mailing
with extremely low traffic. Everyone is encouraged to subscribe to keep in
touch with the current status of project. To subscribe use the Web interface
at http://lists.sourceforge.net/mailman/listinfo/ttf2pt1-announce.
If you have only e-mail access to the Net then send a subscribe request to
the development mailing list ttf2pt1-devel@lists.sourceforge.net and somebody
will help you with subscription.
ttf2pt1-users@lists.sourceforge.net
The ttf2pt1 mailing lists for development and users issues. They have not
that much traffic either. To subscribe use the Web interface at
http://lists.sourceforge.net/mailman/listinfo/ttf2pt1-devel
and http://lists.sourceforge.net/mailman/listinfo/ttf2pt1-users.
If you have only e-mail access to the Net then send a subscribe request to
the development mailing list ttf2pt1-devel@lists.sourceforge.net and somebody
will help you with subscription.
The main page of the project.
http://www.netspace.net.au/~mheath/ttf2pt1/
The old main page of the project.
Troubleshooting and bug reports
Have problems with conversion of some font ? The converter dumps core ? Or your printer refuses to understand the converted fonts ? Or some characters are missing ? Or some characters look strange ?
Send the bug reports to the ttf2pt1 development mailing list at ttf2pt1-devel@lists.sourceforge.net.
Try to collect more information about the problem and include it into the bug report. (Of course, even better if you would provide a ready fix, but just a detailed bug report is also good). Provide detailed information about your problem, this will speed up the response greatly. Don't just write ``this font looks strange after conversion'' but describe what's exactly wrong with it: for example, what characters look wrong and what exactly is wrong about their look. Providing a link to the original font file would be also a good idea. Try to do a little troublehooting and report its result. This not only would help with the fix but may also give you a temporary work-around for the bug.
First, enable full warnings with option `-W99', save them to a file and read carefully. Sometimes the prolem is with a not implemented feature which is reported in the warnings. Still, reporting about such problems may be a good idea: some features were missed to cut corners, in hope that no real font is using them. So a report about a font using such a feature may motivate someone to implement it. Of course, you may be the most motivated person: after all, you are the one wishing to convert that font. ;-) Seriously, the philosophy ``scrath your own itch'' seems to be the strongest moving force behind the Open Source software.
The next step is playing with the options. This serves a dual purpose: on one hand, it helps to localize the bug, on the other hand you may be able to get a working version of the font for the meantime while the bug is being fixed. The typical options to try out are: first `-Ou', if it does not help then `-Os', then `-Oh', then `-Oo'. They are described in a bit more detail above. Try them one by one and in combinations. See if with them the resulting fonts look better.
On some fonts ttf2pt1 just crashes. Commonly that happens because the font being converted is highly defective (although sometimes the bug is in ttf2pt1 itself). In any case it should not crash, so the reports about such cases will help to handle these defects properly in future.
We try to respond to the bug reports in a timely fashion but alas, this may not always be possible, especially if the problem is complex. This is a volunteer project and its resources are limited. Because of this we would appreciate bug reports as detailed as possible, and we would appreciate the ready fixes and contributions even more.
Modification by Mark Heath.
Further modification by Sergey Babkin.
The Type1 assembler by I. Lee Hetherington with modifications by Kai-Uwe Herbing.