home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Collection of Tools & Utilities
/
Collection of Tools and Utilities.iso
/
print
/
gs261ini.zip
/
FONTS.DOC
< prev
next >
Wrap
Text File
|
1993-05-18
|
12KB
|
269 lines
Copyright (C) 1990, 1991 Aladdin Enterprises. All rights reserved.
This file is part of Ghostscript.
Ghostscript is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY. No author or distributor accepts responsibility
to anyone for the consequences of using it or for whether it serves any
particular purpose or works at all, unless he says so in writing. Refer
to the Ghostscript General Public License for full details.
Everyone is granted permission to copy, modify and redistribute
Ghostscript, but only under the conditions described in the Ghostscript
General Public License. A copy of this license is supposed to have been
given to you along with Ghostscript so you can know your rights and
responsibilities. It should be in a file named COPYING. Among other
things, the copyright notice and this notice must be preserved on all
copies.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
This file, fonts.doc, describes the fonts and font facilities supplied
with Ghostscript.
For an overview of Ghostscript and a list of the documentation files, see
README.
About Ghostscript fonts
=======================
The fonts included with Ghostscript come in several parts:
- Font data in files *.gsf: each file defines one
(transformable) font specified in outline form.
- BuildChar procedures in gs_fonts.ps: these provide the
algorithms for interpreting the data in the .gsf files.
- The Fontmap file: this relates Ghostscript font names to .gsf
file names.
Currently, most of the fonts supplied with Ghostscript are based on
various public domain bitmap fonts, primarily the ones supplied with the
X11 distribution from MIT, and on the public domain Hershey fonts. The
fonts are distributed in the file `ghostscript-N.NNfonts.tar.Z'. The
bitmap-derived fonts include the usual Helvetica, Times-Roman, and so on;
see the file `Fontmap' for the complete list, in the usual roman, italic,
bold, and bold italic styles (for the most part). The Hershey fonts, on
the other hand, are quite different from traditional ones; the file
`hershey.doc' describes them in more detail.
There is also a single rather heavy home-grown font called Ugly. This
font is the file `uglyr.gsf' in the Ghostscript source distribution.
The file gs_fonts.ps, which is loaded as part of Ghostscript
initialization, arranges to load fonts on demand using the information
from Fontmap. If you want to preload all of the known fonts, invoke the
procedure
loadallfonts
This is not done by default, since the fonts occupy about 50K each and there
are a lot of them.
Ghostscript fonts are actually ordinary Ghostscript programs: they use the
extension .gsf instead of .ps simply to be informative. This convention
is only embodied in the Fontmap file: there is no code that knows about
it.
If you want to try out the fonts, prfont.ps contains code for printing a
sampler. Load this program, by including it in the gs command line or by
invoking
(prfont.ps) run
and then to produce a sampler of a particular font, invoke
/fontName DoFont
e.g.
/Times-Roman DoFont
Contents of fonts
-----------------
A Ghostscript font is a dictionary with a standard set of keys as follows.
The keys marked with a * have the same meanings as in P*stScr*pt fonts;
those marked with # have the same meanings as in Adobe Type 1 fonts. Note
that FontName is required; StrokeWidth is required for all stroked or
outlined fonts; and Metrics is not currently supported.
* - FontMatrix <array>: the transformation from character
coordinates to user coordinates.
* - FontType <integer>: the type of the font, either 1 or 3.
* - FontBBox <array>: the bounding box of the font.
* - Encoding <array>: the map from character codes to character
names.
* - FontName <name>: the name of the font.
* - PaintType <integer>: an indication of how to interpret the
character description from CharInfo.
* - StrokeWidth <number>: the stroke width for outline fonts.
* - FontInfo <dictionary>: additional information about the font
(optional, not used by the standard Ghostscript software).
* - UniqueID <integer>: a unique number identifying the font.
* - BuildChar <procedure>: the procedure for showing a character
(not required in type 1 fonts).
# - CharStrings <dictionary>: the map from character names to character
descriptions (relevant only in type 1 fonts).
# - Private <dictionary>: additional information used by the
algorithms for rendering outlines fonts (relevant only in type 1
fonts).
The format of values in the CharStrings and Private dictionaries are
described in the Adobe Type 1 Font Format book.
Adding your own fonts
=====================
Ghostscript can use any Type 1 or Type 3 font that is acceptable to other
PostScript language interpreters. Ghostscript also provides a way to
construct a Type 1 font from a bitmap font in BDF format, which is a
popular format in the Unix world.
If you want to add fonts of your own, you must edit Fontmap to include an
entry for your new font at the end. The format for entries is documented
in the Fontmap file. Since later entries in Fontmap override earlier
entries, any fonts you add will supersede the corresponding fonts supplied
with Ghostscript. Note that the font name in the Fontmap entry must be
the same as the FontName in the font itself.
In the PC world, Type 1 fonts are customarily given names ending in .PFA
or .PFB. Ghostscript can use these directly; you just need to make the
entry in Fontmap. If you are going to use a commercial Type 1 font (such
as fonts obtained in conjunction with Adobe Type Manager) with
Ghostscript, please read carefully the license that accompanies the font;
Aladdin Enterprises and the Free Software Foundation take no
responsibility for any possible violations of such licenses.
If you want to convert a BDF file to a scalable outline, use the program
bdftops.ps (and invoking shell script bdftops.bat or bdftops). Run the
shell command
bdftops <BDF_file_name> [<AFM_file1_name> ...] <your_gsf_file_name>
<font_name> <uniqueID> [<encoding_name>]
e.g.,
bdftops pzdr.bdf ZapfDingbats.afm pzdr.gsf ZapfDingbats 4100000
Then make an entry for the .gsf file in Fontmap as described above. You
may find it helpful to read, and to add an entry to, the fonts.mak file,
which is a makefile for converting the standard Ghostscript fonts.
Precompiling fonts
==================
You can compile any Type 1 font into C and link it into the Ghostscript
executable. (Type 1 fonts include any font whose name ends with .pfa or
.pfb, and it also includes all the Ghostscript .gsf fonts except for the
Hershey fonts.) This doesn't have any effect on rendering speed, but it
eliminates the time for loading the font dynamically, which may make a big
difference in total rendering time, especially for multi-page documents.
(Because of RAM and compiler limitations, you should only use compiled
fonts on MS-DOS systems if you are using a 32-bit compiler such as Watcom
C/386 or djgpp; you will run out of memory if you use compiled fonts with
the Borland compiler.) Fonts that have been precompiled and linked in
this way do not need to appear in the Fontmap, although if they do appear
there, no harm is done.
The utility for precompiling fonts is called font2c. Note that font2c is
a PostScript language program, so you must have Ghostscript already
running to be able to run font2c; you must also have entries in the
Fontmap for the fonts you want to compile.) For example, to precompile
the Times-Italic font,
font2c Times-Italic ptmri.c
where the first argument is the font name and the second is the name of
the .c file. You can use any file name you want, as long as it ends in
.c. It doesn't have to be limited to 8 characters, unless your operating
system requires this. We suggest that you use names xxxx.c, where
xxxx.gsf or xxxx.pfa is the name of the font file in the Fontmap file,
just so you don't have to keep track of