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- Committer: Bazaar Package Importer
- Author(s): Julien Cristau
- Date: 2009-01-19 19:53:29 UTC
- mfrom: (3.1.3 jaunty)
- Revision ID: james.westby@ubuntu.com-20090119195329-yzysic30lu3pzyoy
Tags: 1:1.4-4
* Add upstream URL to the copyright file (closes: #512132).
* Upload with the upstream tarball. For some reason this package had gone
native.
* Upload with the upstream tarball. For some reason this package had gone
native.
- files added:
- debian/watch
- sgml/core
- sgml/ddx
- sgml/fonts
- sgml/graphics
- sgml/input
- sgml/output
- sgml/platforms
- sgml/registry
- sgml/security
- files removed:
- Makefile
- debian/patches
- specs/Composite
- specs/Damage
- specs/Fixes
- specs/Randr
- files modified:
- ChangeLog
- autogen.sh *
added
removed
sgml/fonts.sgml
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<!DOCTYPE article PUBLIC "-//OASIS//DTD DocBook V4.2//EN" [
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<!ENTITY % defs SYSTEM "X11/defs.ent"> %defs;
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]>
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<Article>
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<articleinfo>
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<Title>Fonts in X11R</Title>
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<AUTHOR><firstname>Juliusz</firstname><surname>Chroboczek</surname>
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<EMAIL>jch@freedesktop.org</EMAIL>
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</AUTHOR>
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<PubDate>30 October 2006</PubDate>
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</articleinfo>
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<Sect1>
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<Title>Introduction</Title>
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<Para>
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This document describes the support for fonts in X11R.
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<XRef LinkEnd="sec-installing"> is aimed at the
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casual user wishing to install fonts in X11R the rest of the
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document describes the font support in more detail.
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</Para>
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<Para>
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We assume some familiarity with digital fonts. If anything is not
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clear to you, please consult <XRef LinkEnd="sec-background"> at the end of this document for background
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information.
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</Para>
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<Sect2>
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<Title>Two font systems</Title>
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<Para>
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X11 includes two font systems: the original core X11 fonts
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system, which is present in all implementations of X11, and the Xft
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fonts system, which may not yet be distributed with implementations of
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X11 that are not based on either XFree86 or X11R6.8 or later.
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</Para>
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<Para>
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The core X11 fonts system is directly derived from the fonts system
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included with X11R1 in 1987, which could only use monochrome bitmap
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fonts. Over the years, it has been more or less happily coerced into
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dealing with scalable fonts and rotated glyphs.
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</Para>
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<Para>
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Xft was designed from the start to provide good support for scalable
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fonts, and to do so efficiently. Unlike the core fonts system, it
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supports features such as anti-aliasing and sub-pixel rasterisation.
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Perhaps more importantly, it gives applications full control over the
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way glyphs are rendered, making fine typesetting and WYSIWIG display
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possible. Finally, it allows applications to use fonts that are not
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installed system-wide for displaying documents with embedded fonts.
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</Para>
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<Para>
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Xft is not compatible with the core fonts system: usage of Xft
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requires fairly extensive changes to toolkits (user-interface
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libraries). While X.Org will continue to maintain the core fonts
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system, toolkit authors are encouraged to switch to Xft as soon as
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possible.
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</Para>
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</Sect2>
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</Sect1>
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<Sect1 id="sec-installing" xreflabel="Installing fonts">
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<Title>Installing fonts</Title>
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<Para>
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This section explains how to configure both Xft and the core fonts
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system to access newly-installed fonts.
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</Para>
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<Sect2 id="sec-configuring-xft">
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<Title>Configuring Xft</Title>
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<Para>
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Xft has no configuration mechanism itself, it relies upon the
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fontconfig library to configure and customise fonts. That library is
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not specific to the X Window system, and does not rely on any
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particular font output mechanism.
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</Para>
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<Sect3>
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<Title>Installing fonts in Xft</Title>
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<Para>
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Fontconfig looks for fonts in a set of well-known directories that
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include all of X11R's standard font directories
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(`<Literal remap="tt">/usr/X11R6/lib/X11/lib/fonts/*</Literal>') by default) as well as a
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directory called `<Literal remap="tt">.fonts/</Literal>' in the user's home directory.
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Installing a font for use by Xft applications is as simple
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as copying a font file into one of these directories.
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<Screen>
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$ cp lucbr.ttf ~/.fonts/
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</Screen>
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Fontconfig will notice the new font at the next opportunity and rebuild its
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list of fonts. If you want to trigger this update from the command
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line, you may run the command `<Literal remap="tt">fc-cache</Literal>'.
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<Screen>
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$ fc-cache
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</Screen>
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</Para>
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<Para>
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In order to globally update the system-wide Fontconfig information on
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Unix systems, you will typically need to run this command as root:
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<Screen>
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$ su -c fc-cache
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</Screen>
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</Para>
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</Sect3>
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<Sect3>
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<Title>Fine-tuning Xft</Title>
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<Para>
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Fontconfig's behaviour is controlled by a set of configuration
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files: a standard configuration file, `<Literal remap="tt">/etc/fonts/fonts.conf</Literal>',
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a host-specific configuration file, `<Literal remap="tt">/etc/fonts/local.conf</Literal>',
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and a user-specific file called `<Literal remap="tt">.fonts.conf</Literal>' in the user's
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home directory (this can be overridden with the
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`<Literal remap="tt">FONTCONFIG_FILE</Literal>' environment variable).
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</Para>
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<Para>
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Every Fontconfig configuration file must start with the following
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boilerplate:
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<Screen>
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<?xml version="1.0"?>
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<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
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<fontconfig>
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</Screen>
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In addition, every Fontconfig configuration file must end with the
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following line:
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<Screen>
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</fontconfig>
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</Screen>
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</Para>
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<Para>
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The default Fontconfig configuration file includes the directory
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`<Literal remap="tt">˜/.fonts/</Literal>' in the list of directories searched for font
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files, and this is where user-specific font files should be installed.
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In the unlikely case that a new font directory needs to be added, this
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can be done with the following syntax:
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<Screen>
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<dir>/usr/local/share/fonts/</dir>
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</Screen>
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</Para>
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<Para>
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Another useful option is the ability to disable anti-aliasing (font
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smoothing) for selected fonts. This can be done with the following
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syntax:
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<Screen>
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<match target="font">
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<test qual="any" name="family">
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<string>Lucida Console</string>
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</test>
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<edit name="antialias" mode="assign">
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<bool>false</bool>
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</edit>
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</match>
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</Screen>
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Anti-aliasing can be disabled for all fonts by the following incantation:
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<Screen>
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<match target="font">
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<edit name="antialias" mode="assign">
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<bool>false</bool>
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</edit>
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</match>
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</Screen>
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</Para>
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<Para>
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Xft supports sub-pixel rasterisation on LCD displays. X11R should
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automatically enable this feature on laptops and when using an LCD
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monitor connected with a DVI cable; you can check whether this was
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done by typing
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<Screen>
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$ xdpyinfo -ext RENDER | grep sub-pixel
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</Screen>
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If this doesn't print anything, you will need to configure Render for
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your particular LCD hardware manually; this is done with the following
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syntax:
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<Screen>
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<match target="font">
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<edit name="rgba" mode="assign">
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<const>rgb</const>
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</edit>
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</match>
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</Screen>
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The string `<Literal remap="tt">rgb</Literal>' within the
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`<Literal remap="tt"><const></Literal>'...`<Literal remap="tt"></const></Literal>'
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specifies the order of pixel components on your display, and should be
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changed to match your hardware; it can be one of `<Literal remap="tt">rgb</Literal> (normal
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LCD screen), `<Literal remap="tt">bgr</Literal>' (backwards LCD screen), `<Literal remap="tt">vrgb</Literal>' (LCD
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screen rotated clockwise) or `<Literal remap="tt">vbgr</Literal>' (LCD screen rotated
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counterclockwise).
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</Para>
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</Sect3>
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<Sect3>
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<Title>Configuring applications</Title>
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<Para>
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A growing number of applications use Xft in preference to the core
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fonts system. Some applications, however, need to be explicitly
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configured to use Xft.
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</Para>
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<Para>
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A case in point is XTerm, which can be set to use Xft by using the
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`<Literal remap="tt">-fa</Literal>' command line option or by setting the `<Literal remap="tt">XTerm*faceName</Literal>'
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resource:
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<Screen>
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XTerm*faceName: Courier
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</Screen>
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or
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<Screen>
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$ xterm -fa "Courier"
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</Screen>
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</Para>
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<Para>
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For KDE applications, you should select ``Anti-alias fonts'' in the
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``Fonts'' panel of KDE's ``Control Center''. Note that this option is
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misnamed: it switches KDE to using Xft but doesn't enable
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anti-aliasing in case it was disabled by your Xft configuration file.
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</Para>
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<Para>
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Gnome applications and Mozilla Firefox will use Xft by default.
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</Para>
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</Sect3>
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</Sect2>
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<Sect2>
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<Title>Configuring the core X11 fonts system</Title>
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<Para>
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Installing fonts in the core system is a two step process. First,
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you need to create a <Emphasis remap="it">font directory</Emphasis> that contains all the
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relevant font files as well as some index files. You then need to
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inform the X server of the existence of this new directory by
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including it in the <Emphasis remap="it">font path</Emphasis>.
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</Para>
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<Sect3>
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<Title>Installing bitmap fonts</Title>
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<Para>
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The X11R server can use bitmap fonts in both the cross-platform
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BDF format and the somewhat more efficient binary PCF format.
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(X11R also supports the obsolete SNF format.)
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</Para>
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<Para>
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Bitmap fonts are normally distributed in the BDF format. Before
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installing such fonts, it is desirable (but not absolutely necessary)
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to convert the font files to the PCF format. This is done by using the
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command `<Literal remap="tt">bdftopcf</Literal>', <Emphasis remap="it">e.g.</Emphasis>
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<Screen>
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$ bdftopcf courier12.bdf
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</Screen>
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You will then want to compress the resulting PCF font files:
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<Screen>
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$ gzip courier12.pcf
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</Screen>
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</Para>
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<Para>
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After the fonts have been converted, you should copy all the font
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files that you wish to make available into a arbitrary directory, say
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`<Literal remap="tt">/usr/local/share/fonts/bitmap/</Literal>'. You should then create the
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index file `<Literal remap="tt">fonts.dir</Literal>' by running the command `<Literal remap="tt">mkfontdir</Literal>'
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(please see the <ULink
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URL="mkfontdir.1.html"
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>mkfontdir(1)</ULink
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>
320
manual page for more information):
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<Screen>
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$ mkdir /usr/local/share/fonts/bitmap/
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$ cp *.pcf.gz /usr/local/share/fonts/bitmap/
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$ mkfontdir /usr/local/share/fonts/bitmap/
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</Screen>
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</Para>
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<Para>
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All that remains is to tell the X server about the existence of the
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new font directory; see <XRef LinkEnd="sec-set-font-path"> below.
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</Para>
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</Sect3>
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<Sect3>
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<Title>Installing scalable fonts</Title>
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<Para>
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The X11R server supports scalable fonts in multiple
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formats, including Type 1, TrueType, OpenType/CFF and CIDFont.
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This section only applies to the first three; for information on
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CIDFonts, please see <XRef LinkEnd="sec-cid-fonts">
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later in this document. (Earlier versions of X11 also included
346
support for the Speedo scalable font format, but that is disabled in
347
the default builds of X11R6.9 and not included in X11R7.0 and later
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releases.)
349
</Para>
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<Para>
352
Installing scalable fonts is very similar to installing bitmap fonts:
353
you create a directory with the font files, and run `<Literal remap="tt">mkfontdir</Literal>'
354
to create an index file called `<Literal remap="tt">fonts.dir</Literal>'.
355
</Para>
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<Para>
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There is, however, a big difference: `<Literal remap="tt">mkfontdir</Literal>' cannot
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automatically recognise scalable font files. For that reason, you
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must first index all the font files in a file called
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`<Literal remap="tt">fonts.scale</Literal>'. While this can be done by hand, it is best done
362
by using the `<Literal remap="tt">mkfontscale</Literal>' utility.
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<Screen>
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$ mkfontscale /usr/local/share/fonts/Type1/
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$ mkfontdir /usr/local/share/fonts/Type1/
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</Screen>
368
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Under some circumstances, it may be necessary to modify the
370
`<Literal remap="tt">fonts.scale</Literal>' file generated by <Literal remap="tt">mkfontscale</Literal>; for more
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information, please see the <ULink
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URL="mkfontdir.1.html"
373
>mkfontdir(1)</ULink
374
> and <ULink
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URL="mkfontscale.1.html"
376
>mkfontscale(1)</ULink
377
> manual pages and <XRef LinkEnd="sec-internationalisation">
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later in this document.
379
</Para>
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</Sect3>
382
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<Sect3 id="sec-cid-fonts" xreflabel="Installing CIDFonts">
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<Title>Installing CID-keyed fonts </Title>
385
386
<Para>
387
The CID-keyed font format was designed by Adobe Systems for fonts
388
with large character sets. The CID-keyed format is obsolete, as it
389
has been superseded by other formats such as OpenType/CFF; however,
390
support for CID-keyed fonts is still provided in X11.
391
</Para>
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<Para>
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A CID-keyed font, or CIDFont for short, contains a collection of
395
glyphs indexed by <Emphasis remap="it">character ID</Emphasis> (CID).
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</Para>
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<Para>
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In order to map such glyphs to meaningful indices, Adobe provide a set
400
of <Emphasis remap="it">CMap</Emphasis> files. The PostScript name of a font generated from a
401
CIDFont consists of the name of the CIDFont and the name of the CMap
402
separated by two dashes. For example, the font generated from the
403
CIDFont `<Literal remap="tt">Munhwa-Regular</Literal>' using the CMap `<Literal remap="tt">UniKS-UCS2-H</Literal>' is
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called
405
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<Screen>
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Munhwa-Regular--UniKS-UCS2-H
408
</Screen>
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410
</Para>
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<Para>
413
The CIDFont code in X11R requires a very rigid directory
414
structure. The main directory must be called `<Literal remap="tt">CID</Literal>' (its location
415
defaults to `<Literal remap="tt">/usr/X11R6/lib/X11/fonts/CID</Literal>' but it may be
416
located anywhere), and it should contain a subdirectory for every CID
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collection. Every subdirectory <Emphasis remap="it">must</Emphasis> contain subdirectories
418
called <Literal remap="tt">CIDFont</Literal> (containing the actual CIDFont files), <Literal remap="tt">CMap</Literal>
419
(containing all the needed CMaps), <Literal remap="tt">AFM</Literal> (containing the font
420
metric files) and <Literal remap="tt">CFM</Literal> (initially empty). For example, in the
421
case of the font <Literal remap="tt">Munhwa-Regular</Literal> that uses the CID collection
422
<Literal remap="tt">Adobe-Korea1-0</Literal>, the directory structure should be as follows:
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<Screen>
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CID/Adobe-Korea1/CIDFont/Munhwa-Regular
426
CID/Adobe-Korea1/CMap/UniKS-UCS2-H
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CID/Adobe-Korea1/AFM/Munhwa-Regular.afm
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CID/Adobe-Korea1/CFM/
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CID/fonts.dir
430
CID/fonts.scale
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</Screen>
432
433
</Para>
434
435
<Para>
436
After creating this directory structure and copying the relevant
437
files, you should create a `<Literal remap="tt">fonts.scale</Literal>' file. This file has the
438
same format as in the case of (non-CID) scalable fonts, except that
439
its first column contains PostScript font names with the extension
440
`<Literal remap="tt">.cid</Literal>' appended rather than actual filenames:
441
442
<Screen>
443
1
444
Adobe-Korea1/Munhwa-Regular--UniKS-UCS2-H.cid \
445
-adobe-munhwa-medium-r-normal--0-0-0-0-p-0-iso10646-1
446
</Screen>
447
448
(both names on the same line). Running `<Literal remap="tt">mkfontdir</Literal>'
449
creates the `<Literal remap="tt">fonts.dir</Literal>' file:
450
451
<Screen>
452
$ cd /usr/local/share/fonts/CID
453
$ mkfontdir
454
</Screen>
455
456
</Para>
457
458
<Para>
459
Finally, you should create the font metrics summary files in the
460
directory `<Literal remap="tt">CFM</Literal>' by running the command `<Literal remap="tt">mkcfm</Literal>':
461
462
<Screen>
463
$ mkcfm /usr/local/share/fonts/CID
464
</Screen>
465
466
If no CFM files are available, the server will still be able to use
467
the CID fonts but querying them will take a long time. You should run
468
`<Literal remap="tt">mkcfm</Literal>' again whenever a change is made to any of the CID-keyed
469
fonts, or when the CID-keyed fonts are copied to a machine with a
470
different architecture.
471
</Para>
472
473
</Sect3>
474
475
<Sect3 id="sec-set-font-path" xreflabel="Setting the server font path">
476
<Title>Setting the server's font path </Title>
477
478
<Para>
479
The list of directories where the server looks for fonts is known
480
as the <Emphasis remap="it">font path</Emphasis>. Informing the server of the existence of a new
481
font directory consists of putting it on the font path.
482
</Para>
483
484
<Para>
485
The font path is an ordered list; if a client's request matches
486
multiple fonts, the first one in the font path is the one that gets
487
used. When matching fonts, the server makes two passes over the font
488
path: during the first pass, it searches for an exact match; during
489
the second, it searches for fonts suitable for scaling.
490
</Para>
491
492
<Para>
493
For best results, scalable fonts should appear in the font path before
494
the bitmap fonts; this way, the server will prefer bitmap fonts to
495
scalable fonts when an exact match is possible, but will avoid scaling
496
bitmap fonts when a scalable font can be used. (The `<Literal remap="tt">:unscaled</Literal>'
497
hack, while still supported, should no longer be necessary in X11R.)
498
</Para>
499
500
<Para>
501
You may check the font path of the running server by typing the command
502
503
<Screen>
504
$ xset q
505
</Screen>
506
507
</Para>
508
509
<Sect4>
510
<Title>Temporary modification of the font path</Title>
511
512
<Para>
513
The `<Literal remap="tt">xset</Literal>' utility may be used to modify the font path for the
514
current session. The font path is set with the command <Literal remap="tt">xset fp</Literal>;
515
a new element is added to the front with <Literal remap="tt">xset +fp</Literal>, and added to
516
the end with <Literal remap="tt">xset fp+</Literal>. For example,
517
518
<Screen>
519
$ xset +fp /usr/local/fonts/Type1
520
$ xset fp+ /usr/local/fonts/bitmap
521
</Screen>
522
523
</Para>
524
525
<Para>
526
Conversely, an element may be removed from the front of the font path
527
with `<Literal remap="tt">xset -fp</Literal>', and removed from the end with `<Literal remap="tt">xset fp-</Literal>'.
528
You may reset the font path to its default value with
529
`<Literal remap="tt">xset fp default</Literal>'.
530
</Para>
531
532
<Para>
533
For more information, please consult the <ULink
534
URL="xset.1.html"
535
>xset(1)</ULink
536
> manual page.
537
</Para>
538
539
</Sect4>
540
541
<Sect4>
542
<Title>Permanent modification of the font path</Title>
543
544
<Para>
545
The default font path (the one used just after server startup or
546
after `<Literal remap="tt">xset fp default</Literal>') is specified in the X server's
547
`<Literal remap="tt">xorg.conf</Literal>' file. It is computed by appending all the
548
directories mentioned in the `<Literal remap="tt">FontPath</Literal>' entries of the
549
`<Literal remap="tt">Files</Literal>' section in the order in which they appear.
550
551
<Screen>
552
FontPath "/usr/local/fonts/Type1"
553
...
554
FontPath "/usr/local/fonts/bitmap"
555
</Screen>
556
557
</Para>
558
559
<Para>
560
For more information, please consult the <ULink
561
URL="xorg.conf.5.html"
562
>xorg.conf(5)</ULink
563
> manual page.
564
</Para>
565
566
</Sect4>
567
568
</Sect3>
569
570
<Sect3 id="sec-troubleshooting-core">
571
<Title>Troubleshooting </Title>
572
573
<Para>
574
If you seem to be unable to use some of the fonts you have
575
installed, the first thing to check is that the `<Literal remap="tt">fonts.dir</Literal>' files
576
are correct and that they are readable by the server (the X server
577
usually runs as root, beware of NFS-mounted font directories). If
578
this doesn't help, it is quite possible that you are trying to use a
579
font in a format that is not supported by your server.
580
</Para>
581
582
<Para>
583
X11R supports the BDF, PCF, SNF, Type 1, TrueType, OpenType
584
and CIDFont font formats. However, not all X11R servers
585
come with all the font backends configured in.
586
</Para>
587
588
<Para>
589
On most platforms, the X11R servers are <Emphasis remap="it">modular</Emphasis>: the font
590
backends are included in modules that are loaded at runtime. The
591
modules to be loaded are specified in the `<Literal remap="tt">xorg.conf</Literal>' file using
592
the `<Literal remap="tt">Load</Literal>' directive:
593
594
<Screen>
595
Load "type1"
596
</Screen>
597
598
If you have trouble installing fonts in a specific format, you may
599
want to check the server's log file in order to see whether the
600
relevant modules are properly loaded. The list of font modules
601
distributed with X11R is as follows:
602
603
<ItemizedList>
604
<ListItem>
605
606
<Para>
607
<Literal remap="tt">"bitmap"</Literal>: bitmap fonts (`<Literal remap="tt">*.bdf</Literal>', `<Literal remap="tt">*.pcf</Literal>'
608
and `<Literal remap="tt">*.snf</Literal>');
609
</Para>
610
</ListItem>
611
<ListItem>
612
613
<Para>
614
<Literal remap="tt">"freetype"</Literal>: TrueType fonts (`<Literal remap="tt">*.ttf</Literal>' and
615
`<Literal remap="tt">*.ttc</Literal>'), OpenType fonts (`<Literal remap="tt">*.otf</Literal>' and `<Literal remap="tt">*.otc</Literal>') and
616
Type 1 fonts (`<Literal remap="tt">*.pfa</Literal>' and `<Literal remap="tt">*.pfb</Literal>');
617
</Para>
618
</ListItem>
619
<ListItem>
620
621
<Para>
622
<Literal remap="tt">"type1"</Literal>: alternate Type 1 backend (`<Literal remap="tt">*.pfa</Literal>' and
623
`<Literal remap="tt">*.pfb</Literal>') and CIDFont backend;
624
</Para>
625
</ListItem>
626
<ListItem>
627
628
<Para>
629
<Literal remap="tt">"xtt"</Literal>: alternate TrueType backend (`<Literal remap="tt">*.ttf</Literal>' and
630
`<Literal remap="tt">*.ttc</Literal>').
631
</Para>
632
</ListItem>
633
634
</ItemizedList>
635
636
Please note that the argument of the `<Literal remap="tt">Load</Literal>' directive is
637
case-sensitive.
638
</Para>
639
640
</Sect3>
641
642
</Sect2>
643
644
</Sect1>
645
646
<Sect1>
647
<Title>Fonts included with X11R</Title>
648
649
<Sect2>
650
<Title>Standard bitmap fonts</Title>
651
652
<Para>
653
The Sample Implementation of X11 (SI) comes with a large number of
654
bitmap fonts, including the `<Literal remap="tt">fixed</Literal>' family, and bitmap versions
655
of Courier, Times, Helvetica and some members of the Lucida family. In
656
the SI, these fonts are provided in the ISO 8859-1 encoding (ISO
657
Latin Western-European).
658
</Para>
659
660
<Para>
661
In X11R, a number of these fonts are provided in Unicode-encoded
662
font files instead. At build time, these fonts are split into font
663
files encoded according to legacy encodings, a process which allows
664
us to provide the standard fonts in a number of regional encodings
665
with no duplication of work.
666
</Para>
667
668
<Para>
669
For example, the font file
670
671
<Screen>
672
/usr/X11R6/lib/X11/fonts/misc/6x13.bdf
673
</Screen>
674
675
with XLFD
676
677
<Screen>
678
-misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso10646-1
679
</Screen>
680
681
is a Unicode-encoded version of the standard `<Literal remap="tt">fixed</Literal>' font with
682
added support for the Latin, Greek, Cyrillic, Georgian, Armenian, IPA
683
and other scripts plus numerous technical symbols. It contains over
684
2800 glyphs, covering all characters of ISO 8859 parts 1-5,
685
7-10, 13-15, as well as all European IBM and Microsoft code pages,
686
KOI8, WGL4, and the repertoires of many other character sets.
687
</Para>
688
689
<Para>
690
This font is used at build time for generating the font files
691
692
<Screen>
693
6x13-ISO8859-1.bdf
694
6x13-ISO8859-2.bdf
695
...
696
6x13-ISO8859-15.bdf
697
6x13-KOI8-R.bdf
698
</Screen>
699
700
with respective XLFDs
701
702
<Screen>
703
-misc-fixed-medium-r-normal--13-120-75-75-c-60-iso8859-1
704
...
705
-misc-fixed-medium-r-normal--13-120-75-75-c-60-iso8859-15
706
-misc-fixed-medium-r-normal--13-120-75-75-c-60-koi8-r
707
</Screen>
708
709
The standard short name `<Literal remap="tt">fixed</Literal>' is normally an alias for
710
711
<Screen>
712
-misc-fixed-medium-r-normal--13-120-75-75-c-60-iso8859-1
713
</Screen>
714
715
</Para>
716
717
</Sect2>
718
719
<Sect2>
720
<Title>The ClearlyU Unicode font family</Title>
721
722
<Para>
723
The ClearlyU family of fonts provides a set of 12 pt,
724
100 dpi proportional fonts with many of the glyphs needed for
725
Unicode text. Together, the fonts contain approximately 7500 glyphs.
726
</Para>
727
728
<Para>
729
The main ClearlyU font has the XLFD
730
731
<Screen>
732
-mutt-clearlyu-medium-r-normal--17-120-100-100-p-101-iso10646-1
733
</Screen>
734
735
and resides in the font file
736
737
<Screen>
738
/usr/X11R6/lib/X11/fonts/misc/cu12.pcf.gz
739
</Screen>
740
741
Additional ClearlyU fonts include
742
743
<Screen>
744
-mutt-clearlyu alternate glyphs-medium-r-normal--17-120-100-100-p-91-iso10646-1
745
-mutt-clearlyu pua-medium-r-normal--17-120-100-100-p-111-iso10646-1
746
-mutt-clearlyu arabic extra-medium-r-normal--17-120-100-100-p-103-fontspecific-0
747
-mutt-clearlyu ligature-medium-r-normal--17-120-100-100-p-141-fontspecific-0
748
</Screen>
749
750
</Para>
751
752
<Para>
753
The <Emphasis remap="it">Alternate Glyphs</Emphasis> font contains additional glyph shapes that
754
are needed for certain languages. A second alternate glyph font will
755
be provided later for cases where a character has more than one
756
commonly used alternate shape (<Emphasis remap="it">e.g.</Emphasis> the Urdu heh).
757
</Para>
758
759
<Para>
760
The <Emphasis remap="it">PUA</Emphasis> font contains extra glyphs that are useful for certain
761
rendering purposes.
762
</Para>
763
764
<Para>
765
The <Emphasis remap="it">Arabic Extra</Emphasis> font contains the glyphs necessary for
766
characters that don't have all of their possible shapes encoded in
767
ISO 10646. The glyphs are roughly ordered according to the order
768
of the characters in the ISO 10646 standard.
769
</Para>
770
771
<Para>
772
The <Emphasis remap="it">Ligature</Emphasis> font contains ligatures for various scripts that
773
may be useful for improved presentation of text.
774
</Para>
775
776
</Sect2>
777
778
<Sect2>
779
<Title>Standard scalable fonts</Title>
780
781
<Para>
782
X11R includes all the scalable fonts distributed with X11R6.
783
</Para>
784
785
<Sect3>
786
<Title>Standard Type 1 fonts</Title>
787
788
<Para>
789
The IBM Courier set of fonts cover ISO 8859-1 and
790
ISO 8859-2 as well as Adobe Standard Encoding. These fonts have
791
XLFD
792
793
<Screen>
794
-adobe-courier-medium-*-*--0-0-0-0-m-0-*-*
795
</Screen>
796
797
and reside in the font files
798
799
<Screen>
800
/usr/X11R6/lib/X11/fonts/Type1/cour*.pfa
801
</Screen>
802
803
</Para>
804
805
<Para>
806
The Adobe Utopia set of fonts only cover ISO 8859-1 as well as
807
Adobe Standard Encoding. These fonts have XLFD
808
809
<Screen>
810
-adobe-utopia-*-*-normal--0-0-0-0-p-0-iso8859-1
811
</Screen>
812
813
and reside in the font files
814
815
<Screen>
816
/usr/X11R6/lib/X11/fonts/Type1/UT*.pfa
817
</Screen>
818
819
</Para>
820
821
<Para>
822
Finally, X11R also comes with Type 1 versions of Bitstream
823
Courier and Charter. These fonts have XLFD
824
825
<Screen>
826
-bitstream-courier-*-*-normal--0-0-0-0-m-0-iso8859-1
827
-bitstream-charter-*-*-normal--0-0-0-0-p-0-iso8859-1
828
</Screen>
829
830
and reside in the font files
831
832
<Screen>
833
/usr/X11R6/lib/X11/fonts/Type1/c*bt_.pfb
834
</Screen>
835
836
</Para>
837
838
</Sect3>
839
840
</Sect2>
841
842
<Sect2>
843
<Title>The Bigelow & Holmes Luxi family</Title>
844
845
<Para>
846
X11R includes the <Emphasis remap="it">Luxi</Emphasis> family of scalable fonts, in both
847
TrueType and Type 1 format. This family consists of the fonts
848
<Emphasis remap="it">Luxi Serif</Emphasis>, with XLFD
849
850
<Screen>
851
-b&h-luxi serif-medium-*-normal--*-*-*-*-p-*-*-*
852
</Screen>
853
854
<Emphasis remap="it">Luxi Sans</Emphasis>, with XLFD
855
856
<Screen>
857
-b&h-luxi sans-medium-*-normal--*-*-*-*-p-*-*-*
858
</Screen>
859
860
and <Emphasis remap="it">Luxi Mono</Emphasis>, with XLFD
861
862
<Screen>
863
-b&h-luxi mono-medium-*-normal--*-*-*-*-m-*-*-*
864
</Screen>
865
866
Each of these fonts comes Roman, oblique, bold and bold oblique variants
867
The TrueType version have glyphs covering the basic ASCII Unicode
868
range, the Latin 1 range, as well as the <Emphasis remap="it">Extended Latin</Emphasis>
869
range and some additional punctuation characters. In particular,
870
these fonts include all the glyphs needed for ISO 8859 parts 1,
871
2, 3, 4, 9, 13 and 15, as well as all the glyphs in the Adobe Standard
872
encoding and the Windows 3.1 character set.
873
</Para>
874
875
<Para>
876
The glyph coverage of the Type 1 versions is somewhat reduced,
877
and only covers ISO 8859 parts 1, 2 and 15 as well as the Adobe
878
Standard encoding.
879
</Para>
880
881
<Para>
882
The Luxi fonts are original designs by Kris Holmes and Charles
883
Bigelow. Luxi fonts include seriffed, sans serif, and monospaced
884
styles, in roman and oblique, and normal and bold weights. The fonts
885
share stem weight, x-height, capital height, ascent and descent, for
886
graphical harmony.
887
</Para>
888
889
<Para>
890
The character width metrics of Luxi roman and bold fonts match those
891
of core fonts bundled with popular operating and window systems.
892
</Para>
893
894
<Para>
895
The license terms for the Luxi fonts are included in the file
896
`<Literal remap="tt">COPYRIGHT.BH</Literal>', as well as in the <ULink
897
URL="LICENSE.html"
898
>License document</ULink
899
>.
900
</Para>
901
902
<Para>
903
Charles Bigelow and Kris Holmes from Bigelow and Holmes Inc.
904
developed the Luxi typeface designs in Ikarus digital format.
905
</Para>
906
907
<Para>
908
URW++ Design and Development GmbH converted the Ikarus format fonts
909
to TrueType and Type1 font programs and implemented the grid-fitting
910
"hints" and kerning tables in the Luxi fonts.
911
</Para>
912
913
<Para>
914
For more information, please contact
915
<EMAIL
916
>design@bigelowandholmes.com</EMAIL
917
> or
918
<EMAIL
919
>info@urwpp.de</EMAIL
920
>, or consult
921
<ULink
922
URL="http://www.urwpp.de"
923
>the URW++ web site</ULink
924
>.
925
</Para>
926
927
<Para>
928
An earlier version of the Luxi fonts was made available under the
929
name <Emphasis>Lucidux</Emphasis>. This name should no longer be used due to trademark
930
uncertainties, and all traces of the <Emphasis>Lucidux</Emphasis> name have been
931
removed from X11R.
932
</Para>
933
934
</Sect2>
935
936
</Sect1>
937
938
<Sect1 id="sec-more-core">
939
<Title>More about core fonts </Title>
940
941
<Para>
942
This section describes X11R-specific enhancements to the core
943
X11 fonts system.
944
</Para>
945
946
<Sect2 id="sec-internationalisation" xreflabel="Core fonts and
947
internationalisation">
948
<Title>Core fonts and internationalisation </Title>
949
950
<Para>
951
The scalable font backends (Type 1 and TrueType) can
952
automatically re-encode fonts to the encoding specified in the
953
XLFD in `<Literal remap="tt">fonts.dir</Literal>'. For example, a `<Literal remap="tt">fonts.dir</Literal>' file can
954
contain entries for the Type 1 Courier font such as
955
956
<Screen>
957
cour.pfa -adobe-courier-medium-r-normal--0-0-0-0-m-0-iso8859-1
958
cour.pfa -adobe-courier-medium-r-normal--0-0-0-0-m-0-iso8859-2
959
</Screen>
960
961
which will lead to the font being recoded to ISO 8859-1 and
962
ISO 8859-2 respectively.
963
</Para>
964
965
<Sect3 id="sec-fontenc">
966
<Title>The <Emphasis remap="it">fontenc</Emphasis> layer </Title>
967
968
<Para>
969
Two of the scalable backends (Type 1 and the
970
<Emphasis remap="it">FreeType</Emphasis> TrueType backend) use a common <Emphasis remap="it">fontenc</Emphasis> layer for
971
font re-encoding. This allows these backends to share their encoding
972
data, and allows simple configuration of new locales independently of
973
font type.
974
</Para>
975
976
<Para>
977
<Emphasis remap="it">Please note:</Emphasis> the X-TrueType (X-TT) backend is not included
978
in X11R. That functionality has been merged into the FreeType
979
backend.>
980
</Para>
981
982
<Para>
983
In the <Emphasis remap="it">fontenc</Emphasis> layer, an encoding is defined by a name (such as
984
<Literal remap="tt">iso8859-1</Literal>), possibly a number of aliases (alternate names), and
985
an ordered collection of mappings. A mapping defines the way the
986
encoding can be mapped into one of the <Emphasis remap="it">target encodings</Emphasis> known to
987
<Emphasis remap="it">fontenc</Emphasis>; currently, these consist of Unicode, Adobe glyph names,
988
and arbitrary TrueType ``cmap''s.
989
</Para>
990
991
<Para>
992
A number of encodings are hardwired into <Emphasis remap="it">fontenc</Emphasis>, and are
993
therefore always available; the hardcoded encodings cannot easily be
994
redefined. These include:
995
996
<ItemizedList>
997
<ListItem>
998
999
<Para>
1000
<Literal remap="tt">iso10646-1</Literal>: Unicode;
1001
</Para>
1002
</ListItem>
1003
<ListItem>
1004
1005
<Para>
1006
<Literal remap="tt">iso8859-1</Literal>: ISO Latin-1 (Western Europe);
1007
</Para>
1008
</ListItem>
1009
<ListItem>
1010
1011
<Para>
1012
<Literal remap="tt">iso8859-2</Literal>: ISO Latin-2 (Eastern Europe);
1013
</Para>
1014
</ListItem>
1015
<ListItem>
1016
1017
<Para>
1018
<Literal remap="tt">iso8859-3</Literal>: ISO Latin-3 (Southern Europe);
1019
</Para>
1020
</ListItem>
1021
<ListItem>
1022
1023
<Para>
1024
<Literal remap="tt">iso8859-4</Literal>: ISO Latin-4 (Northern Europe);
1025
</Para>
1026
</ListItem>
1027
<ListItem>
1028
1029
<Para>
1030
<Literal remap="tt">iso8859-5</Literal>: ISO Cyrillic;
1031
</Para>
1032
</ListItem>
1033
<ListItem>
1034
1035
<Para>
1036
<Literal remap="tt">iso8859-6</Literal>: ISO Arabic;
1037
</Para>
1038
</ListItem>
1039
<ListItem>
1040
1041
<Para>
1042
<Literal remap="tt">iso8859-7</Literal>: ISO Greek;
1043
</Para>
1044
</ListItem>
1045
<ListItem>
1046
1047
<Para>
1048
<Literal remap="tt">iso8859-8</Literal>: ISO Hebrew;
1049
</Para>
1050
</ListItem>
1051
<ListItem>
1052
1053
<Para>
1054
<Literal remap="tt">iso8859-9</Literal>: ISO Latin-5 (Turkish);
1055
</Para>
1056
</ListItem>
1057
<ListItem>
1058
1059
<Para>
1060
<Literal remap="tt">iso8859-10</Literal>: ISO Latin-6 (Nordic);
1061
</Para>
1062
</ListItem>
1063
<ListItem>
1064
1065
<Para>
1066
<Literal remap="tt">iso8859-15</Literal>: ISO Latin-9, or Latin-0 (Revised
1067
Western-European);
1068
</Para>
1069
</ListItem>
1070
<ListItem>
1071
1072
<Para>
1073
<Literal remap="tt">koi8-r</Literal>: KOI8 Russian;
1074
</Para>
1075
</ListItem>
1076
<ListItem>
1077
1078
<Para>
1079
<Literal remap="tt">koi8-u</Literal>: KOI8 Ukrainian (see RFC 2319);
1080
</Para>
1081
</ListItem>
1082
<ListItem>
1083
1084
<Para>
1085
<Literal remap="tt">koi8-ru</Literal>: KOI8 Russian/Ukrainian;
1086
</Para>
1087
</ListItem>
1088
<ListItem>
1089
1090
<Para>
1091
<Literal remap="tt">koi8-uni</Literal>: KOI8 ``Unified'' (Russian, Ukrainian, and
1092
Byelorussian);
1093
</Para>
1094
</ListItem>
1095
<ListItem>
1096
1097
<Para>
1098
<Literal remap="tt">koi8-e</Literal>: KOI8 ``European,'' ISO-IR-111, or ECMA-Cyrillic;
1099
</Para>
1100
</ListItem>
1101
<ListItem>
1102
1103
<Para>
1104
<Literal remap="tt">microsoft-symbol</Literal> and <Literal remap="tt">apple-roman</Literal>: these are only
1105
likely to be useful with TrueType symbol fonts.
1106
</Para>
1107
</ListItem>
1108
1109
</ItemizedList>
1110
1111
</Para>
1112
1113
<Para>
1114
Additional encodings can be added by defining <Emphasis remap="it">encoding files</Emphasis>.
1115
When a font encoding is requested that the <Emphasis remap="it">fontenc</Emphasis> layer doesn't
1116
know about, the backend checks the directory in which the font file
1117
resides (not necessarily the directory with <Literal remap="tt">fonts.dir</Literal>!) for a
1118
file named `<Literal remap="tt">encodings.dir</Literal>'. If found, this file is scanned for
1119
the requested encoding, and the relevant encoding definition file is
1120
read in. The `<Literal remap="tt">mkfontdir</Literal>' utility, when invoked with the
1121
`<Literal remap="tt">-e</Literal>' option followed by the name of a directory containing
1122
encoding files, can be used to automatically build `<Literal remap="tt">encodings.dir</Literal>'
1123
files. Please see the <ULink
1124
URL="mkfontdir.1.html"
1125
>mkfontdir(1)</ULink
1126
>
1127
manual page for more details.
1128
</Para>
1129
1130
<Para>
1131
A number of encoding files for common encodings are included with
1132
X11R. Information on writing new encoding files can be found in
1133
<XRef LinkEnd="sec-format-encoding-directory-files"> and <XRef LinkEnd="sec-format-encoding-files"> later in this document.
1134
</Para>
1135
1136
</Sect3>
1137
1138
<Sect3>
1139
<Title>Backend-specific notes about fontenc</Title>
1140
1141
<Sect4 id="sec-fontenc-freetype">
1142
<Title>The <Emphasis remap="it">FreeType</Emphasis> backend </Title>
1143
1144
<Para>
1145
For TrueType and OpenType fonts, the FreeType backend scans the
1146
mappings in order. Mappings with a target of PostScript are ignored;
1147
mappings with a TrueType or Unicode target are checked against all the
1148
cmaps in the file. The first applicable mapping is used.
1149
</Para>
1150
1151
<Para>
1152
For Type 1 fonts, the FreeType backend first searches for a
1153
mapping with a target of PostScript. If one is found, it is used.
1154
Otherwise, the backend searches for a mapping with target Unicode,
1155
which is then composed with a built-in table mapping codes to glyph
1156
names. Note that this table only covers part of the Unicode code
1157
points that have been assigned names by Adobe.
1158
</Para>
1159
1160
<Para>
1161
Specifying an encoding value of <Literal remap="tt">adobe-fontspecific</Literal> for a
1162
Type 1 font disables the encoding mechanism. This is useful with
1163
symbol and incorrectly encoded fonts (see <XRef LinkEnd="sec-incorrect-encoding"> below).
1164
</Para>
1165
1166
<Para>
1167
If a suitable mapping is not found, the FreeType backend defaults to
1168
ISO 8859-1.
1169
</Para>
1170
1171
</Sect4>
1172
1173
<Sect4>
1174
<Title>Type 1</Title>
1175
1176
<Para>
1177
The Type 1 backend behaves similarly to the FreeType backend
1178
with Type 1 fonts, except that it limits all encodings to 8-bit
1179
codes.
1180
</Para>
1181
1182
</Sect4>
1183
1184
</Sect3>
1185
1186
<Sect3 id="sec-format-encoding-directory-files" xreflabel="Format of
1187
encodings directory files">
1188
<Title>Format of encoding directory files </Title>
1189
1190
<Para>
1191
In order to use a font in an encoding that the font backend does
1192
not know about, you need to have an `<Literal remap="tt">encodings.dir</Literal>' file either
1193
in the same directory as the font file used or in a system-wide
1194
location (`<Literal remap="tt">/usr/X11R6/lib/X11/fonts/encodings/</Literal>' by default).
1195
</Para>
1196
1197
<Para>
1198
The `<Literal remap="tt">encodings.dir</Literal>' file has a similar format to
1199
`<Literal remap="tt">fonts.dir</Literal>'. Its first line specifies the number of encodings,
1200
while every successive line has two columns, the name of the encoding,
1201
and the name of the encoding file; this can be relative to the current
1202
directory, or absolute. Every encoding name should agree with the
1203
encoding name defined in the encoding file. For example,
1204
</Para>
1205
1206
<Para>
1207
1208
<Screen>
1209
3
1210
mulearabic-0 /usr/X11R6/lib/X11/fonts/encodings/mulearabic-0.enc
1211
mulearabic-1 /usr/X11R6/lib/X11/fonts/encodings/mulearabic-1.enc
1212
mulearabic-2 /usr/X11R6/lib/X11/fonts/encodings/mulearabic-2.enc
1213
</Screen>
1214
1215
</Para>
1216
1217
<Para>
1218
The name of an encoding <Emphasis remap="it">must</Emphasis> be specified in the encoding file's
1219
`<Literal remap="tt">STARTENCODING</Literal>' or `<Literal remap="tt">ALIAS</Literal>' line. It is not enough to create
1220
an `<Literal remap="tt">encodings.dir</Literal>' entry.
1221
</Para>
1222
1223
<Para>
1224
If your platform supports it (it probably does), encoding files may be
1225
compressed or gzipped.
1226
</Para>
1227
1228
<Para>
1229
The `<Literal remap="tt">encoding.dir</Literal>' files are best maintained by the
1230
`<Literal remap="tt">mkfontdir</Literal>' utility. Please see the <ULink
1231
URL="mkfontdir.1.html"
1232
>mkfontdir(1)</ULink
1233
> manual page for more information.
1234
</Para>
1235
1236
</Sect3>
1237
1238
<Sect3 id="sec-format-encoding-files" xreflabel="Format of encoding files">
1239
<Title>Format of encoding files </Title>
1240
1241
<Para>
1242
The encoding files are ``free form,'' <Emphasis remap="it">i.e.</Emphasis> any string of
1243
whitespace is equivalent to a single space. Keywords are parsed in a
1244
non-case-sensitive manner, meaning that `<Literal remap="tt">size</Literal>', `<Literal remap="tt">SIZE</Literal>', and
1245
`<Literal remap="tt">SiZE</Literal>' all parse as the same keyword; on the other hand, case is
1246
significant in glyph names.
1247
</Para>
1248
1249
<Para>
1250
Numbers can be written in decimal, as in `<Literal remap="tt">256</Literal>', in hexadecimal,
1251
as in `<Literal remap="tt">0x100</Literal>', or in octal, as in `<Literal remap="tt">0400</Literal>'.
1252
</Para>
1253
1254
<Para>
1255
Comments are introduced by a hash sign `<Literal remap="tt">#</Literal>'. A `<Literal remap="tt">#</Literal>' may
1256
appear at any point in a line, and all characters following the
1257
`<Literal remap="tt">#</Literal>' are ignored, up to the end of the line.
1258
</Para>
1259
1260
<Para>
1261
The encoding file starts with the definition of the name of the
1262
encoding, and possibly its alternate names (aliases):
1263
1264
<Screen>
1265
STARTENCODING mulearabic-0
1266
ALIAS arabic-0
1267
</Screen>
1268
1269
The name of the encoding and its aliases should be suitable for use in
1270
an XLFD font name, and therefore contain exactly one dash `<Literal remap="tt">-</Literal>'.
1271
</Para>
1272
1273
<Para>
1274
The encoding file may then optionally declare the size of the
1275
encoding. For a linear encoding (such as ISO 8859-1), the SIZE
1276
line specifies the maximum code plus one:
1277
1278
<Screen>
1279
SIZE 0x2B
1280
</Screen>
1281
1282
For a matrix encoding, it should specify two numbers. The first is
1283
the number of the last row plus one, the other, the highest column
1284
number plus one. In the case of `<Literal remap="tt">jisx0208.1990-0</Literal>'
1285
(JIS X 0208(1990), double-byte encoding, high bit clear), it
1286
should be
1287
1288
<Screen>
1289
SIZE 0x75 0x80
1290
</Screen>
1291
1292
In the case of a matrix encoding, a `<Literal remap="tt">FIRSTINDEX</Literal>' line may be
1293
included to specify the minimum glyph index in an encoding. The
1294
keyword `<Literal remap="tt">FIRSTINDEX</Literal>' is followed by two integers, the minimum row
1295
number followed by the minimum column number:
1296
1297
<Screen>
1298
FIRSTINDEX 0x20 0x20
1299
</Screen>
1300
1301
In the case of a linear encoding, a `<Literal remap="tt">FIRSTINDEX</Literal>' line is not very
1302
useful. If for some reason however you chose to include on, it should
1303
be followed by a single integer.
1304
</Para>
1305
1306
<Para>
1307
Note that in most font backends inclusion of a `<Literal remap="tt">FIRSTINDEX</Literal>' line
1308
has the side effect of disabling default glyph generation, and this
1309
keyword should therefore be avoided unless absolutely necessary.
1310
</Para>
1311
1312
<Para>
1313
Codes outside the region defined by the `<Literal remap="tt">SIZE</Literal>' and
1314
`<Literal remap="tt">FIRSTINDEX</Literal>' lines are understood to be undefined. Encodings
1315
default to linear encoding with a size of 256 (0x100). This means
1316
that you must declare the size of all 16 bit encodings.
1317
</Para>
1318
1319
<Para>
1320
What follows is one or more mapping sections. A mapping section
1321
starts with a `<Literal remap="tt">STARTMAPPING</Literal>' line stating the target of the mapping.
1322
The target may be one of:
1323
1324
<ItemizedList>
1325
<ListItem>
1326
1327
<Para>
1328
Unicode (ISO 10646):
1329
1330
<Screen>
1331
STARTMAPPING unicode
1332
</Screen>
1333
1334
</Para>
1335
</ListItem>
1336
<ListItem>
1337
1338
<Para>
1339
a given TrueType ``cmap'':
1340
1341
<Screen>
1342
STARTMAPPING cmap 3 1
1343
</Screen>
1344
1345
</Para>
1346
</ListItem>
1347
<ListItem>
1348
1349
<Para>
1350
PostScript glyph names:
1351
1352
<Screen>
1353
STARTMAPPING postscript
1354
</Screen>
1355
1356
</Para>
1357
</ListItem>
1358
1359
</ItemizedList>
1360
1361
Every line in a mapping section maps one from the encoding being
1362
defined to the target of the mapping. In mappings with a Unicode or
1363
TrueType mapping, codes are mapped to codes:
1364
1365
<Screen>
1366
0x21 0x0660
1367
0x22 0x0661
1368
...
1369
</Screen>
1370
1371
As an abbreviation, it is possible to map a contiguous range of codes
1372
in a single line. A line consisting of three integers
1373
1374
<Screen>
1375
<it/start/ <it/end/ <it/target/
1376
</Screen>
1377
1378
is an abbreviation for the range of lines
1379
1380
<Screen>
1381
<Emphasis remap="it">start</Emphasis> <Emphasis remap="it">target</Emphasis>
1382
</Screen>
1383
1384
<Screen>
1385
<Emphasis remap="it">start</Emphasis>+1 <Emphasis remap="it">target</Emphasis>+1
1386
</Screen>
1387
1388
<Screen>
1389
...
1390
</Screen>
1391
1392
<Screen>
1393
<Emphasis remap="it">end</Emphasis> <Emphasis remap="it">target</Emphasis>+<Emphasis remap="it">end</Emphasis>-<Emphasis remap="it">start</Emphasis>
1394
</Screen>
1395
1396
For example, the line
1397
1398
<Screen>
1399
0x2121 0x215F 0x8140
1400
</Screen>
1401
1402
is an abbreviation for
1403
1404
<Screen>
1405
0x2121 0x8140
1406
0x2122 0x8141
1407
...
1408
0x215F 0x817E
1409
</Screen>
1410
1411
Codes not listed are assumed to map through the identity (<Emphasis remap="it">i.e.</Emphasis> to
1412
the same numerical value). In order to override this default mapping,
1413
you may specify a range of codes to be undefined by using an
1414
`<Literal remap="tt">UNDEFINE</Literal>' line:
1415
1416
<Screen>
1417
UNDEFINE 0x00 0x2A
1418
</Screen>
1419
1420
or, for a single code,
1421
1422
<Screen>
1423
UNDEFINE 0x1234
1424
</Screen>
1425
1426
</Para>
1427
1428
<Para>
1429
PostScript mappings are different. Every line in a PostScript mapping
1430
maps a code to a glyph name
1431
1432
<Screen>
1433
0x41 A
1434
0x42 B
1435
...
1436
</Screen>
1437
1438
and codes not explicitly listed are undefined.
1439
</Para>
1440
1441
<Para>
1442
A mapping section ends with an <Literal remap="tt">ENDMAPPING</Literal> line
1443
1444
<Screen>
1445
ENDMAPPING
1446
</Screen>
1447
1448
After all the mappings have been defined, the file ends with an
1449
<Literal remap="tt">ENDENCODING</Literal> line
1450
1451
<Screen>
1452
ENDENCODING
1453
</Screen>
1454
1455
</Para>
1456
1457
<Para>
1458
In order to make future extensions to the format possible, lines
1459
starting with an unknown keyword are silently ignored, as are mapping
1460
sections with an unknown target.
1461
</Para>
1462
1463
</Sect3>
1464
1465
<Sect3 id="sec-symbol-fonts">
1466
<Title>Using symbol fonts </Title>
1467
1468
<Para>
1469
Type 1 symbol fonts should be installed using the
1470
<Literal remap="tt">adobe-fontspecific</Literal> encoding.
1471
</Para>
1472
1473
<Para>
1474
In an ideal world, all TrueType symbol fonts would be installed using
1475
one of the <Literal remap="tt">microsoft-symbol</Literal> and <Literal remap="tt">apple-roman</Literal> encodings. A
1476
number of symbol fonts, however, are not marked as such; such fonts
1477
should be installed using <Literal remap="tt">microsoft-cp1252</Literal>, or, for older fonts,
1478
<Literal remap="tt">microsoft-win3.1</Literal>.
1479
</Para>
1480
1481
<Para>
1482
In order to guarantee consistent results (especially between
1483
Type 1 and TrueType versions of the same font), it is possible to
1484
define a special encoding for a given font. This has already been done
1485
for the <Literal remap="tt">ZapfDingbats</Literal> font; see the file
1486
`<Literal remap="tt">encodings/adobe-dingbats.enc</Literal>'.
1487
</Para>
1488
1489
</Sect3>
1490
1491
<Sect3 id="sec-incorrect-encoding" xreflabel="Incorrectly encoded fonts">
1492
<Title>Hints about using badly encoded fonts </Title>
1493
1494
<Para>
1495
A number of text fonts are incorrectly encoded. Incorrect encoding
1496
is sometimes done by design, in order to make a font for an exotic
1497
script appear like an ordinary Western text font on systems which are
1498
not easily extended with new locale data. It is often the result of
1499
the font designer's laziness or incompetence; for some reason, most
1500
people seem to find it easier to invent idiosyncratic glyph names
1501
rather than follow the Adobe glyph list.
1502
</Para>
1503
1504
<Para>
1505
There are two ways of dealing with such fonts: using them with the
1506
encoding they were designed for, and creating an <Emphasis remap="it">ad hoc</Emphasis> encoding
1507
file.
1508
</Para>
1509
1510
<Sect4>
1511
<Title>Using fonts with the designer's encoding</Title>
1512
1513
<Para>
1514
In the case of Type 1 fonts, the font designer can specify a
1515
default encoding; this encoding is requested by using the
1516
`<Literal remap="tt">adobe-fontspecific</Literal>' encoding in the XLFD name. Sometimes, the
1517
font designer omitted to specify a reasonable default encoding, in
1518
which case you should experiment with `<Literal remap="tt">adobe-standard</Literal>',
1519
`<Literal remap="tt">iso8859-1</Literal>', `<Literal remap="tt">microsoft-cp1252</Literal>', and
1520
`<Literal remap="tt">microsoft-win3.1</Literal>'. (The encoding `<Literal remap="tt">microsoft-symbol</Literal>' doesn't
1521
make sense for Type 1 fonts).
1522
</Para>
1523
1524
<Para>
1525
TrueType fonts do not have a default encoding. However, most TrueType
1526
fonts are designed with either Microsoft or Apple platforms in mind,
1527
so one of `<Literal remap="tt">microsoft-symbol</Literal>', `<Literal remap="tt">microsoft-cp1252</Literal>',
1528
`<Literal remap="tt">microsoft-win3.1</Literal>', or `<Literal remap="tt">apple-roman</Literal>' should yield reasonable
1529
results.
1530
</Para>
1531
1532
</Sect4>
1533
1534
<Sect4>
1535
<Title>Specifying an <Emphasis remap="it">ad hoc</Emphasis> encoding file</Title>
1536
1537
<Para>
1538
It is always possible to define an encoding file to put the glyphs
1539
in a font in any desired order. Again, see the
1540
`<Literal remap="tt">encodings/adobe-dingbats.enc</Literal>' file to see how this is done.
1541
</Para>
1542
1543
</Sect4>
1544
1545
<Sect4>
1546
<Title>Specifying font aliases</Title>
1547
1548
<Para>
1549
By following the directions above, you will find yourself with a
1550
number of fonts with unusual names --- with encodings such as
1551
`<Literal remap="tt">adobe-fontspecific</Literal>', `<Literal remap="tt">microsoft-win3.1</Literal>' <Emphasis remap="it">etc</Emphasis>. In order
1552
to use these fonts with standard applications, it may be useful to
1553
remap them to their proper names.
1554
</Para>
1555
1556
<Para>
1557
This is done by writing a `<Literal remap="tt">fonts.alias</Literal>' file. The format of this file
1558
is very simple: it consists of a series of lines each mapping an alias
1559
name to a font name. A `<Literal remap="tt">fonts.alias</Literal>' file might look as follows:
1560
1561
<Screen>
1562
"-ogonki-alamakota-medium-r-normal--0-0-0-0-p-0-iso8859-2" \
1563
"-ogonki-alamakota-medium-r-normal--0-0-0-0-p-0-adobe-fontspecific"
1564
</Screen>
1565
1566
(both XLFD names on a single line). The syntax of the
1567
`<Literal remap="tt">fonts.alias</Literal>' file is more precisely described in the
1568
<ULink
1569
URL="mkfontdir.1.html"
1570
>mkfontdir(1)</ULink
1571
> manual page.
1572
</Para>
1573
1574
</Sect4>
1575
1576
</Sect3>
1577
1578
</Sect2>
1579
1580
<Sect2>
1581
<Title>Additional notes about scalable core fonts</Title>
1582
1583
<Para>
1584
The FreeType (libfreetype-xtt2) backend (module `<Literal remap="tt">freetype</Literal>',
1585
formerly known as <Emphasis remap="it">xfsft</Emphasis>) is able to deal with both TrueType and
1586
Type 1 fonts. This puts it in conflict with the X-TT and Type 1
1587
backends respectively.
1588
</Para>
1589
1590
<Para>
1591
If both the FreeType and the Type 1 backends are loaded, the
1592
FreeType backend will be used for Type 1 fonts. If both the
1593
FreeType and X-TT backends are loaded, X-TT will be used for TrueType
1594
fonts.
1595
</Para>
1596
1597
<Sect3>
1598
<Title>About the <Emphasis remap="it">FreeType</Emphasis> backend</Title>
1599
1600
<Para>
1601
The <Emphasis remap="it">FreeType</Emphasis> (libfreetype-xtt2) backend (formerly <Emphasis remap="it">xfsft</Emphasis>)
1602
is a backend based on version 2 of the FreeType library (see <ULink
1603
URL="http://www.freetype.org/"
1604
>the FreeType web site</ULink
1605
>) and has
1606
the X-TT functionalities for CJKV support provided by the After X-TT
1607
Project (see <ULink
1608
URL="http://x-tt.sourceforge.jp/"
1609
>the After X-TT Project web site</ULink
1610
>). The <Emphasis remap="it">FreeType</Emphasis> module has support for the
1611
``fontenc'' style of internationalisation (see <XRef LinkEnd="sec-fontenc">). This backend supports TrueType font files
1612
(`<Literal remap="tt">*.ttf</Literal>'), OpenType font files (`<Literal remap="tt">*.otf</Literal>'), TrueType Collections
1613
(`<Literal remap="tt">*.ttc</Literal>'), OpenType Collections (`<Literal remap="tt">*.otc</Literal>') and Type 1 font
1614
files (`<Literal remap="tt">*.pfa</Literal>' and `<Literal remap="tt">*.pfb</Literal>').
1615
</Para>
1616
1617
<Para>
1618
In order to access the faces in a TrueType Collection file, the face
1619
number must be specified in the fonts.dir file before the filename,
1620
within a pair of colons, or by setting the 'fn' TTCap option. For example,
1621
</Para>
1622
1623
<Para>
1624
1625
<Screen>
1626
:1:mincho.ttc -misc-pmincho-medium-r-normal--0-0-0-0-p-0-jisx0208.1990-0
1627
</Screen>
1628
1629
</Para>
1630
1631
<Para>
1632
refers to face 1 in the `<Literal remap="tt">mincho.ttc</Literal>' TrueType Collection file.
1633
</Para>
1634
1635
<Para>
1636
The new <Emphasis remap="it">FreeType</Emphasis> backend supports the extended
1637
`<Literal remap="tt">fonts.dir</Literal>' syntax introduced by X-TrueType with a number
1638
of options, collectively known as `TTCap'. A `TTCap' entry follows the
1639
general syntax
1640
</Para>
1641
1642
<Para>
1643
1644
<Screen>
1645
option=value:
1646
</Screen>
1647
1648
</Para>
1649
1650
<Para>
1651
and should be specified before the filename. The new <Emphasis remap="it">FreeType</Emphasis>
1652
almost perfectly supports TTCap options that are compatible with X-TT
1653
1.4. The Automatic Italic (`<Literal remap="tt">ai</Literal>'), Double Strike (`<Literal remap="tt">ds</Literal>') and
1654
Bounding box Width (`<Literal remap="tt">bw</Literal>') options are indispensable in CJKV.
1655
For example,
1656
</Para>
1657
1658
<Para>
1659
1660
<Screen>
1661
mincho.ttc -misc-mincho-medium-r-normal--0-0-0-0-c-0-jisx0208.1990-0
1662
ds=y:mincho.ttc -misc-mincho-bold-r-normal--0-0-0-0-c-0-jisx0208.1990-0
1663
ai=0.2:mincho.ttc -misc-mincho-medium-i-normal--0-0-0-0-c-0-jisx0208.1990-0
1664
ds=y:ai=0.2:mincho.ttc -misc-mincho-bold-i-normal--0-0-0-0-c-0-jisx0208.1990-0
1665
bw=0.5:mincho.ttc -misc-mincho-medium-r-normal--0-0-0-0-c-0-jisx0201.1976-0
1666
bw=0.5:ds=y:mincho.ttc -misc-mincho-bold-r-normal--0-0-0-0-c-0-jisx0201.1976-0
1667
bw=0.5:ai=0.2:mincho.ttc -misc-mincho-medium-i-normal--0-0-0-0-c-0-jisx0201.1976-0
1668
bw=0.5:ds=y:ai=0.2:mincho.ttc -misc-mincho-bold-i-normal--0-0-0-0-c-0-jisx0201.1976-0
1669
</Screen>
1670
1671
</Para>
1672
1673
<Para>
1674
setup the complete combination of jisx0208 and jisx0201 using mincho.ttc
1675
only. More information on the TTCap syntax is found on <ULink
1676
URL="http://x-tt.sourceforge.jp/"
1677
>the After X-TT Project page</ULink
1678
>.
1679
</Para>
1680
1681
<Para>
1682
The <Emphasis remap="it">FreeType</Emphasis> backend uses the <Emphasis remap="it">fontenc</Emphasis> layer in order to support
1683
recoding of fonts; this was described in <XRef LinkEnd="sec-fontenc"> and especially <XRef LinkEnd="sec-fontenc-freetype"> earlier in this document.
1684
</Para>
1685
1686
</Sect3>
1687
1688
<Sect3 id="sec-X-TT">
1689
<Title>About the <Emphasis remap="it">X-TrueType</Emphasis> TrueType backend </Title>
1690
1691
<Para>
1692
The `X-TrueType' backend is a backend based on version 1 of the FreeType
1693
library. X-TrueType doesn't use the `fontenc' layer for managing font
1694
encodings, but instead uses its own database of encodings.
1695
</Para>
1696
1697
<Para>
1698
Since the functionalities for CJKV support introduced by X-TT have been
1699
merged into the new <Emphasis remap="it">FreeType</Emphasis> backend, the X-TT backend will be
1700
removed from X11R's tree near the future. Therefore, the use of
1701
<Emphasis remap="it">FreeType</Emphasis> backend is preferred over the X-TT backend.
1702
</Para>
1703
1704
<Para>
1705
General information on X-TrueType may be found at <ULink
1706
URL="http://x-tt.sourceforge.jp/"
1707
>the After X-TT Project page</ULink
1708
>.
1709
</Para>
1710
1711
</Sect3>
1712
1713
<Sect3>
1714
<Title>Delayed glyph rasterisation</Title>
1715
1716
<Para>
1717
When loading a proportional fonts which contain a huge number of glyphs,
1718
the old <Emphasis remap="it">FreeType</Emphasis> delayed glyph rasterisation until the time at which
1719
the glyph was first used. The new FreeType (libfreetype-xtt2) has an
1720
improved `very lazy' metric calculation method to speed up the process when
1721
loading TrueType or OpenType fonts. Although the <Emphasis remap="it">X-TT</Emphasis> module also
1722
has this method, the "<Literal remap="tt">vl=y</Literal>" TTCap option must be set if you want to
1723
use it. This is the default method for <Emphasis remap="it">FreeType</Emphasis> when it loads
1724
multi-byte fonts. Even if you use a unicode font which has tens of
1725
thousands of glyphs, this delay will not be worrisome as long as you use
1726
the new <Emphasis remap="it">FreeType</Emphasis> backend -- its `very lazy' method is super-fast.
1727
</Para>
1728
1729
<Para>
1730
The maximum error of bitmap position using `very lazy' method is 1 pixel,
1731
and is the same as that of a character-cell spacing. When the X-TT
1732
backend is used with the `<Literal remap="tt">vl=y</Literal>' option, a chipped bitmap is displayed
1733
with certain fonts. However, the new FreeType backend has minimal problem
1734
with this, since it corrects left- and right-side bearings using
1735
`italicAngle' in the TrueType/OpenType post table, and does automatic
1736
correction of bitmap positions when rasterisation so that chipped bitmaps
1737
are not displayed. Nevertheless if you don't want to use the `very lazy'
1738
method when using multi-bytes fonts, set `<Literal remap="tt">vl=n</Literal>' in the TTCap option to
1739
disable it:
1740
</Para>
1741
1742
<Para>
1743
1744
<Screen>
1745
vl=n:luxirr.ttf -b&h-Luxi Serif-medium-r-normal--0-0-0-0-p-0-iso10646-1
1746
</Screen>
1747
1748
</Para>
1749
1750
<Para>
1751
Of course, both backends also support an optimisation for character-cell
1752
fonts (fonts with all glyph metrics equal, or terminal fonts). A font
1753
with an XLFD specifying a character-cell spacing `<Literal remap="tt">c</Literal>', as in
1754
</Para>
1755
1756
<Para>
1757
1758
<Screen>
1759
-misc-mincho-medium-r-normal--0-0-0-0-c-0-jisx0208.1990-0
1760
</Screen>
1761
1762
</Para>
1763
1764
<Para>
1765
or
1766
</Para>
1767
1768
<Para>
1769
1770
<Screen>
1771
fs=c:mincho.ttc -misc-mincho-medium-r-normal--0-0-0-0-p-0-jisx0208.1990-0
1772
</Screen>
1773
1774
</Para>
1775
1776
<Para>
1777
will not compute the metric for each glyph, but instead
1778
trust the font to be a character-cell font. You are
1779
encouraged to make use of this optimisation when useful, but be warned
1780
that not all monospaced fonts are character-cell fonts.
1781
</Para>
1782
1783
</Sect3>
1784
1785
</Sect2>
1786
1787
</Sect1>
1788
1789
<Sect1 id="sec-background" xreflabel="Appendix: Background">
1790
<Title>Appendix: background and terminology </Title>
1791
1792
<Sect2>
1793
<Title>Characters and glyphs</Title>
1794
1795
<Para>
1796
A computer text-processing system inputs keystrokes and outputs
1797
<Emphasis remap="it">glyphs</Emphasis>, small pictures that are assembled on paper or on a
1798
computer screen. Keystrokes and glyphs do not, in general, coincide:
1799
for example, if the system does generate ligatures, then to the
1800
sequence of two keystrokes <<Literal remap="tt">f</Literal>><<Literal remap="tt">i</Literal>> will typically
1801
correspond a single glyph. Similarly, if the system shapes Arabic
1802
glyphs in a vaguely reasonable manner, then multiple different glyphs
1803
may correspond to a single keystroke.
1804
</Para>
1805
1806
<Para>
1807
The complex transformation rules from keystrokes to glyphs are usually
1808
factored into two simpler transformations, from keystrokes to
1809
<Emphasis remap="it">characters</Emphasis> and from characters to glyphs. You may want to think
1810
of characters as the basic unit of text that is stored <Emphasis remap="it">e.g.</Emphasis> in
1811
the buffer of your text editor. While the definition of a character
1812
is intrinsically application-specific, a number of standardised
1813
collections of characters have been defined.
1814
</Para>
1815
1816
<Para>
1817
A <Emphasis remap="it">coded character set</Emphasis> is a set of characters together with a
1818
mapping from integer codes --- known as <Emphasis remap="it">codepoints</Emphasis> --- to
1819
characters. Examples of coded character sets include US-ASCII,
1820
ISO 8859-1, KOI8-R, and JIS X 0208(1990).
1821
</Para>
1822
1823
<Para>
1824
A coded character set need not use 8 bit integers to index characters.
1825
Many early systems used 6 bit character sets, while 16 bit (or more)
1826
character sets are necessary for ideographic writing systems.
1827
</Para>
1828
1829
</Sect2>
1830
1831
<Sect2 id="sec-xlfd">
1832
<Title>Font files, fonts, and XLFD </Title>
1833
1834
<Para>
1835
Traditionally, typographers speak about <Emphasis remap="it">typefaces</Emphasis> and
1836
<Emphasis remap="it">founts</Emphasis>. A typeface is a particular style or design, such as
1837
Times Italic, while a fount is a molten-lead incarnation of a given
1838
typeface at a given size.
1839
</Para>
1840
1841
<Para>
1842
Digital fonts come in <Emphasis remap="it">font files</Emphasis>. A font file contains the
1843
information necessary for generating glyphs of a given typeface, and
1844
applications using font files may access glyph information in an
1845
arbitrary order.
1846
</Para>
1847
1848
<Para>
1849
Digital fonts may consist of bitmap data, in which case they are said
1850
to be <Emphasis remap="it">bitmap fonts</Emphasis>. They may also consist of a mathematical
1851
description of glyph shapes, in which case they are said to be
1852
<Emphasis remap="it">scalable fonts</Emphasis>. Common formats for scalable font files are
1853
<Emphasis remap="it">Type 1</Emphasis> (sometimes incorrectly called <Emphasis remap="it">ATM fonts</Emphasis> or
1854
<Emphasis remap="it">PostScript fonts</Emphasis>), <Emphasis remap="it">TrueType</Emphasis> and <Emphasis remap="it">OpenType</Emphasis>.
1855
</Para>
1856
1857
<Para>
1858
The glyph data in a digital font needs to be indexed somehow. How
1859
this is done depends on the font file format. In the case of
1860
Type 1 fonts, glyphs are identified by <Emphasis remap="it">glyph names</Emphasis>. In the
1861
case of TrueType fonts, glyphs are indexed by integers corresponding
1862
to one of a number of indexing schemes (usually Unicode --- see below).
1863
</Para>
1864
1865
<Para>
1866
The X11 core fonts system uses the data in a font file to generate
1867
<Emphasis remap="it">font instances</Emphasis>, which are collections of glyphs at a given size
1868
indexed according to a given encoding.
1869
</Para>
1870
1871
<Para>
1872
X11 core font instances are usually specified using a notation known
1873
as the <Emphasis remap="it">X Logical Font Description</Emphasis> (XLFD). An XLFD starts with a
1874
dash `<Literal remap="tt">-</Literal>', and consists of fourteen fields separated by dashes,
1875
for example:
1876
1877
<Screen>
1878
-adobe-courier-medium-r-normal--12-120-75-75-m-70-iso8859-1
1879
</Screen>
1880
1881
Or particular interest are the last two fields `<Literal remap="tt">iso8859-1</Literal>', which
1882
specify the font instance's encoding.
1883
</Para>
1884
1885
<Para>
1886
A scalable font is specified by an XLFD which contains zeroes instead
1887
of some fields:
1888
1889
<Screen>
1890
-adobe-courier-medium-r-normal--0-0-0-0-m-0-iso8859-1
1891
</Screen>
1892
1893
</Para>
1894
1895
<Para>
1896
X11 font instances may also be specified by short name. Unlike an
1897
XLFD, a short name has no structure and is simply a conventional name
1898
for a font instance. Two short names are of particular interest, as
1899
the server will not start if font instances with these names cannot be
1900
opened. These are `<Literal remap="tt">fixed</Literal>', which specifies the fallback font to
1901
use when the requested font cannot be opened, and `<Literal remap="tt">cursor</Literal>', which
1902
specifies the set of glyphs to be used by the mouse pointer.
1903
</Para>
1904
1905
<Para>
1906
Short names are usually implemented as aliases to XLFDs; the
1907
standard `<Literal remap="tt">fixed</Literal>' and `<Literal remap="tt">cursor</Literal>' aliases are defined in
1908
1909
<Screen>
1910
/usr/X11R6/lib/X11/font/misc/fonts.alias
1911
</Screen>
1912
1913
</Para>
1914
1915
</Sect2>
1916
1917
<Sect2>
1918
<Title>Unicode</Title>
1919
1920
<Para>
1921
Unicode (<ULink
1922
URL="http://www.unicode.org"
1923
>�</ULink
1924
>) is a coded character
1925
set with the goal of uniquely identifying all characters for all
1926
scripts, current and historical. While Unicode was explicitly not
1927
designed as a glyph encoding scheme, it is often possible to use it as
1928
such.
1929
</Para>
1930
1931
<Para>
1932
Unicode is an <Emphasis remap="it">open</Emphasis> character set, meaning that codepoint
1933
assignments may be added to Unicode at any time (once specified,
1934
though, an assignment can never be changed). For this reason, a
1935
Unicode font will be <Emphasis remap="it">sparse</Emphasis>, meaning that it only defines glyphs
1936
for a subset of the character registry of Unicode.
1937
</Para>
1938
1939
<Para>
1940
The Unicode standard is defined in parallel with the international
1941
standard ISO 10646. Assignments in the two standards are always
1942
equivalent, and we often use the terms <Emphasis remap="it">Unicode</Emphasis> and
1943
<Emphasis remap="it">ISO 10646</Emphasis> interchangeably.
1944
</Para>
1945
1946
<Para>
1947
When used in the X11 core fonts system, Unicode-encoded fonts should
1948
have the last two fields of their XLFD set to `<Literal remap="tt">iso10646-1</Literal>'.
1949
</Para>
1950
1951
</Sect2>
1952
1953
</Sect1>
1954
1955
<Sect1>
1956
<Title>References</Title>
1957
1958
<Para>
1959
X11R comes with extensive documentation in the form of manual
1960
pages and typeset documents. Before installing fonts, you really should
1961
read the <ULink
1962
URL="fontconfig.3.html"
1963
>fontconfig(3)</ULink
1964
> and
1965
<ULink
1966
URL="mkfontdir.1.html"
1967
>mkfontdir(1)</ULink
1968
> manual pages; other
1969
manual pages of interest include <ULink
1970
URL="X.7.html"
1971
>X(7)</ULink
1972
>,
1973
<ULink
1974
URL="Xserver.1.html"
1975
>Xserver(1)</ULink
1976
>, <ULink
1977
URL="xset.1.html"
1978
>xset(1)</ULink
1979
>, <ULink
1980
URL="Xft.3.html"
1981
>Xft(3)</ULink
1982
>, <ULink
1983
URL="xlsfonts.1.html"
1984
>xlsfonts(1)</ULink
1985
> and <ULink
1986
URL="showfont.1.html"
1987
>showfont(1)</ULink
1988
>. In addition, you may want to read the X Logical
1989
Font Description document, by Jim Flowers, which is provided in the file
1990
`<Literal remap="tt">xc/doc/xlfd.PS.Z</Literal>'.
1991
</Para>
1992
1993
<Para>
1994
The <ULink
1995
URL="http://www.faqs.org/faqs/by-newsgroup/comp/comp.fonts.html"
1996
>comp.fonts FAQ</ULink
1997
>,
1998
which is unfortunately no longer being maintained, contains a wealth
1999
of information about digital fonts.
2000
</Para>
2001
2002
<Para>
2003
Xft and Fontconfig are described on
2004
<ULink
2005
URL="http://www.fontconfig.org"
2006
>Keith Packard's Fontconfig site</ULink
2007
>.
2008
</Para>
2009
2010
<Para>
2011
The
2012
<ULink
2013
URL="http://www.dcs.ed.ac.uk/home/jec/programs/xfsft/"
2014
>xfsft home page</ULink
2015
>
2016
has been superseded by this document, and is now obsolete; you may
2017
however still find some of the information that it contains useful.
2018
<ULink
2019
URL="http://www.joerg-pommnitz.de/TrueType/xfsft.html"
2020
>Joerg Pommnitz' xfsft page</ULink
2021
>
2022
is the canonical source for the `<Literal remap="tt">ttmkfdir</Literal>' utility, which is the
2023
ancestor of <Literal remap="tt">mkfontscale</Literal>.
2024
</Para>
2025
2026
<Para>
2027
<ULink
2028
URL="http://www.pps.jussieu.fr/~jch/software/"
2029
>The author's software pages</ULink
2030
>
2031
might or might not contain related scribbles and development versions
2032
of software.
2033
</Para>
2034
2035
<Para>
2036
The documentation of <Emphasis remap="it">X-TrueType</Emphasis> is available from <ULink
2037
URL="http://x-tt.sourceforge.jp/"
2038
>the After X-TT Project page</ULink
2039
>.
2040
</Para>
2041
2042
<Para>
2043
A number of East-Asian CIDFonts are available from
2044
<ULink
2045
URL="ftp://ftp.oreilly.com/pub/examples/nutshell/cjkv/adobe/"
2046
>O'Reilly's FTP site</ULink
2047
>.
2048
</Para>
2049
2050
<Para>
2051
While the <ULink
2052
URL="http://www.unicode.org"
2053
>Unicode consortium site</ULink
2054
>
2055
may be of interest, you are more likely to find what you need in
2056
Markus Kuhn's <ULink
2057
URL="http://www.cl.cam.ac.uk/~mgk25/unicode.html"
2058
>UTF-8 and Unicode FAQ</ULink
2059
>.
2060
</Para>
2061
2062
<Para>
2063
The IANA RFC documents, available from a number of sites throughout
2064
the world, often provide interesting information about character set
2065
issues; see for example RFC 373.
2066
</Para>
2067
2068
</Sect1>
2069
2070
</Article>
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