<!ENTITY confdir SYSTEM "confdir.sgml">
]>
<!--
- $Id$
-
Copyright © 2003 Keith Packard
Permission to use, copy, modify, distribute, and sell this software and its
representations about the suitability of this software for any purpose. It
is provided "as is" without express or implied warranty.
- KEITH PACKARD DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ THE AUTHOR(S) DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
- EVENT SHALL KEITH PACKARD BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY SPECIAL, INDIRECT OR
CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
<refsect2><title>Font Configuration</title>
<para>
The configuration module consists of the FcConfig datatype, libexpat and
-FcConfigParse which walks over an XML tree and ammends a configuration with
+FcConfigParse which walks over an XML tree and amends a configuration with
data found within. From an external perspective, configuration of the
library consists of generating a valid XML tree and feeding that to
FcConfigParse. The only other mechanism provided to applications for
While font patterns may contain essentially any properties, there are some
well known properties with associated types. Fontconfig uses some of these
properties for font matching and font completion. Others are provided as a
-convenience for the applications rendering mechanism.
+convenience for the applications' rendering mechanism.
</para>
<programlisting>
Property Type Description
--------------------------------------------------------------
family String Font family names
- familylang String Languages cooresponding to each family
+ familylang String Languages corresponding to each family
style String Font style. Overrides weight and slant
- stylelang String Languages cooresponding to each style
+ stylelang String Languages corresponding to each style
fullname String Font full names (often includes style)
- fullnamelang String Languages cooresponding to each fullname
+ fullnamelang String Languages corresponding to each fullname
slant Int Italic, oblique or roman
weight Int Light, medium, demibold, bold or black
size Double Point size
dpi Double Target dots per inch
rgba Int unknown, rgb, bgr, vrgb, vbgr,
none - subpixel geometry
+ lcdfilter Int Type of LCD filter
minspace Bool Eliminate leading from line spacing
charset CharSet Unicode chars encoded by the font
lang String List of RFC-3066-style languages this
Monospace:matrix=1 .1 0 1 The users preferred monospace font
with artificial obliquing
</programlisting>
+ <para>
+The '\', '-', ':' and ',' characters in family names must be preceeded by a
+'\' character to avoid having them misinterpreted. Similarly, values
+containing '\', '=', '_', ':' and ',' must also have them preceeded by a
+'\' character. The '\' characters are stripped out of the family name and
+values as the font name is read.
+ </para>
</refsect2>
</refsect1>
+<refsect1><title>Debugging Applications</title>
+ <para>
+To help diagnose font and applications problems, fontconfig is built with a
+large amount of internal debugging left enabled. It is controlled by means
+of the FC_DEBUG environment variable. The value of this variable is
+interpreted as a number, and each bit within that value controls different
+debugging messages.
+ </para>
+ <programlisting>
+ Name Value Meaning
+ ---------------------------------------------------------
+ MATCH 1 Brief information about font matching
+ MATCHV 2 Extensive font matching information
+ EDIT 4 Monitor match/test/edit execution
+ FONTSET 8 Track loading of font information at startup
+ CACHE 16 Watch cache files being written
+ CACHEV 32 Extensive cache file writing information
+ PARSE 64 (no longer in use)
+ SCAN 128 Watch font files being scanned to build caches
+ SCANV 256 Verbose font file scanning information
+ MEMORY 512 Monitor fontconfig memory usage
+ CONFIG 1024 Monitor which config files are loaded
+ LANGSET 2048 Dump char sets used to construct lang values
+ OBJTYPES 4096 Display message when value typechecks fail
+ </programlisting>
+ <para>
+Add the value of the desired debug levels together and assign that (in
+base 10) to the FC_DEBUG environment variable before running the
+application. Output from these statements is sent to stdout.
+ </para>
+</refsect1>
<refsect1><title>Lang Tags</title>
<para>
Each font in the database contains a list of languages it supports. This is
</para>
<refsect2><title><literal><fontconfig></literal></title><para>
This is the top level element for a font configuration and can contain
-<sgmltag>dir</>, <sgmltag>cache</>, <sgmltag>include</>, <sgmltag>match</> and <sgmltag>alias</> elements in any order.
+<literal><dir></literal>, <literal><cache></literal>, <literal><include></literal>, <literal><match></literal> and <literal><alias></literal> elements in any order.
</para></refsect2>
- <refsect2><title><sgmltag>dir</></title><para>
+ <refsect2><title><literal><dir></literal></title><para>
This element contains a directory name which will be scanned for font files
to include in the set of available fonts.
</para></refsect2>
- <refsect2><title><sgmltag>cache</></title><para>
+ <refsect2><title><literal><cache></literal></title><para>
This element contains a file name for the per-user cache of font
information. If it starts with '~', it refers to a file in the users
home directory. This file is used to hold information about fonts that
isn't present in the per-directory cache files. It is automatically
maintained by the fontconfig library. The default for this file
-is ``~/.fonts.cache-<sgmltag>version</>'', where <sgmltag>version</> is the font configuration
-file version number (currently 1).
+is ``~/.fonts.cache-<literal><version></literal>'', where <literal><version></literal> is the font configuration
+file version number (currently 2).
</para></refsect2>
- <refsect2><title><sgmltag>include ignore_missing="no"</></title><para>
+ <refsect2><title><literal><include ignore_missing="no"></literal></title><para>
This element contains the name of an additional configuration file or
-directory. If a directory, every file within that directory starting with a
-number will be processed in sorted order. When
+directory. If a directory, every file within that directory starting with an
+ASCII digit (U+0030 - U+0039) and ending with the string ``.conf'' will be processed in sorted order. When
the XML datatype is traversed by FcConfigParse, the contents of the file(s)
will also be incorporated into the configuration by passing the filename(s) to
FcConfigLoadAndParse. If 'ignore_missing' is set to "yes" instead of the
default "no", a missing file or directory will elicit no warning message from
the library.
</para></refsect2>
- <refsect2><title><sgmltag>config</></title><para>
-This element provides a place to consolodate additional configuration
-information. <sgmltag>config</> can contain <sgmltag>blank</> and <sgmltag>rescan</> elements in any
+ <refsect2><title><literal><config></literal></title><para>
+This element provides a place to consolidate additional configuration
+information. <literal><config></literal> can contain <literal><blank></literal> and <literal><rescan></literal> elements in any
order.
</para></refsect2>
- <refsect2><title><sgmltag>blank</></title><para>
+ <refsect2><title><literal><blank></literal></title><para>
Fonts often include "broken" glyphs which appear in the encoding but are
-drawn as blanks on the screen. Within the <sgmltag>blank</> element, place each
-Unicode characters which is supposed to be blank in an <sgmltag>int</> element.
+drawn as blanks on the screen. Within the <literal><blank></literal> element, place each
+Unicode characters which is supposed to be blank in an <literal><int></literal> element.
Characters outside of this set which are drawn as blank will be elided from
the set of characters supported by the font.
</para></refsect2>
- <refsect2><title><sgmltag>rescan</></title><para>
-The <sgmltag>rescan</> element holds an <sgmltag>int</> element which indicates the default
+ <refsect2><title><literal><rescan></literal></title><para>
+The <literal><rescan></literal> element holds an <literal><int></literal> element which indicates the default
interval between automatic checks for font configuration changes.
Fontconfig will validate all of the configuration files and directories and
automatically rebuild the internal datastructures when this interval passes.
</para></refsect2>
- <refsect2><title><sgmltag>selectfont</></title><para>
+ <refsect2><title><literal><selectfont></literal></title><para>
This element is used to black/white list fonts from being listed or matched
against. It holds acceptfont and rejectfont elements.
</para></refsect2>
- <refsect2><title><sgmltag>acceptfont</></title><para>
+ <refsect2><title><literal><acceptfont></literal></title><para>
Fonts matched by an acceptfont element are "whitelisted"; such fonts are
explicitly included in the set of fonts used to resolve list and match
requests; including them in this list protects them from being "blacklisted"
by a rejectfont element. Acceptfont elements include glob and pattern
elements which are used to match fonts.
</para></refsect2>
- <refsect2><title><sgmltag>rejectfont</></title><para>
+ <refsect2><title><literal><rejectfont></literal></title><para>
Fonts matched by an rejectfont element are "blacklisted"; such fonts are
excluded from the set of fonts used to resolve list and match requests as if
they didn't exist in the system. Rejectfont elements include glob and
pattern elements which are used to match fonts.
</para></refsect2>
- <refsect2><title><sgmltag>glob</></title><para>
+ <refsect2><title><literal><glob></literal></title><para>
Glob elements hold shell-style filename matching patterns (including ? and
*) which match fonts based on their complete pathnames. This can be used to
exclude a set of directories (/usr/share/fonts/uglyfont*), or particular
font file types (*.pcf.gz), but the latter mechanism relies rather heavily
-on filenaming conventions which can't be relied upon.
+on filenaming conventions which can't be relied upon. Note that globs
+only apply to directories, not to individual fonts.
</para></refsect2>
- <refsect2><title><sgmltag>pattern</></title><para>
+ <refsect2><title><literal><pattern></literal></title><para>
Pattern elements perform list-style matching on incoming fonts; that is,
they hold a list of elements and associated values. If all of those
elements have a matching value, then the pattern matches the font. This can
etc), which is a more reliable mechanism than using file extensions.
Pattern elements include patelt elements.
</para></refsect2>
- <refsect2><title><sgmltag>patelt name="property"</></title><para>
+ <refsect2><title><literal><patelt name="property"></literal></title><para>
Patelt elements hold a single pattern element and list of values. They must
have a 'name' attribute which indicates the pattern element name. Patelt
elements include int, double, string, matrix, bool, charset and const
elements.
</para></refsect2>
- <refsect2><title><sgmltag>match target="pattern"</></title><para>
-This element holds first a (possibly empty) list of <sgmltag>test</> elements and then
-a (possibly empty) list of <sgmltag>edit</> elements. Patterns which match all of the
+ <refsect2><title><literal><match target="pattern"></literal></title><para>
+This element holds first a (possibly empty) list of <literal><test></literal> elements and then
+a (possibly empty) list of <literal><edit></literal> elements. Patterns which match all of the
tests are subjected to all the edits. If 'target' is set to "font" instead
of the default "pattern", then this element applies to the font name
-resulting from a match rather than a font pattern to be matched.
+resulting from a match rather than a font pattern to be matched. If 'target'
+is set to "scan", then this element applies when the font is scanned to
+build the fontconfig database.
</para></refsect2>
- <refsect2><title><sgmltag>test qual="any" name="property" target="default" compare="eq"</></title><para>
+ <refsect2><title><literal><test qual="any" name="property" target="default" compare="eq"></literal></title><para>
This element contains a single value which is compared with the target
-('pattern', 'font' or 'default') property "property" (substitute any of the property names seen
+('pattern', 'font', 'scan' or 'default') property "property" (substitute any of the property names seen
above). 'compare' can be one of "eq", "not_eq", "less", "less_eq", "more", or
"more_eq". 'qual' may either be the default, "any", in which case the match
succeeds if any value associated with the property matches the test value, or
the original pattern or the font. "default" selects whichever target the
outer <match> element has selected.
</para></refsect2>
- <refsect2><title><sgmltag>edit name="property" mode="assign" binding="weak"</></title><para>
+ <refsect2><title><literal><edit name="property" mode="assign" binding="weak"></literal></title><para>
This element contains a list of expression elements (any of the value or
operator elements). The expression elements are evaluated at run-time and
modify the property "property". The modification depends on whether
-"property" was matched by one of the associated <sgmltag>test</> elements, if so, the
+"property" was matched by one of the associated <literal><test></literal> elements, if so, the
modification may affect the first matched value. Any values inserted into
the property are given the indicated binding ("strong", "weak" or "same")
with "same" binding using the value from the matched pattern element.
"append_last" Append at end of list Append at end of list
</programlisting>
</para></refsect2>
- <refsect2><title><sgmltag>int</>, <sgmltag>double</>, <sgmltag>string</>, <sgmltag>bool</></title><para>
-These elements hold a single value of the indicated type. <sgmltag>bool</>
+ <refsect2><title><literal><int></literal>, <literal><double></literal>, <literal><string></literal>, <literal><bool></literal></title><para>
+These elements hold a single value of the indicated type. <literal><bool></literal>
elements hold either true or false. An important limitation exists in
the parsing of floating point numbers -- fontconfig requires that
the mantissa start with a digit, not a decimal point, so insert a leading
zero for purely fractional values (e.g. use 0.5 instead of .5 and -0.5
instead of -.5).
</para></refsect2>
- <refsect2><title><sgmltag>matrix</></title><para>
-This element holds the four <sgmltag>double</> elements of an affine
+ <refsect2><title><literal><matrix></literal></title><para>
+This element holds the four <literal><double></literal> elements of an affine
transformation.
</para></refsect2>
- <refsect2><title><sgmltag>name</></title><para>
+ <refsect2><title><literal><name></literal></title><para>
Holds a property name. Evaluates to the first value from the property of
the font, not the pattern.
</para></refsect2>
- <refsect2><title><sgmltag>const</></title><para>
+ <refsect2><title><literal><const></literal></title><para>
Holds the name of a constant; these are always integers and serve as
symbolic names for common font values:
<programlisting>
vrgb rgba 3
vbgr rgba 4
none rgba 5
+ lcdnone lcdfilter 0
+ lcddefault lcdfilter 1
+ lcdlight lcdfilter 2
+ lcdlegacy lcdfilter 3
hintnone hintstyle 0
hintslight hintstyle 1
hintmedium hintstyle 2
</para>
</refsect2>
<refsect2>
- <title><sgmltag>or</>, <sgmltag>and</>, <sgmltag>plus</>, <sgmltag>minus</>, <sgmltag>times</>, <sgmltag>divide</></title>
+ <title><literal><or></literal>, <literal><and></literal>, <literal><plus></literal>, <literal><minus></literal>, <literal><times></literal>, <literal><divide></literal></title>
<para>
These elements perform the specified operation on a list of expression
-elements. <sgmltag>or</> and <sgmltag>and</> are boolean, not bitwise.
+elements. <literal><or></literal> and <literal><and></literal> are boolean, not bitwise.
</para>
</refsect2>
<refsect2>
- <title><sgmltag>eq</>, <sgmltag>not_eq</>, <sgmltag>less</>, <sgmltag>less_eq</>, <sgmltag>more</>, <sgmltag>more_eq</></title>
+ <title><literal><eq></literal>, <literal><not_eq></literal>, <literal><less></literal>, <literal><less_eq></literal>, <literal><more></literal>, <literal><more_eq></literal></title>
<para>
These elements compare two values, producing a boolean result.
</para></refsect2>
- <refsect2><title><sgmltag>not</></title><para>
+ <refsect2><title><literal><not></literal></title><para>
Inverts the boolean sense of its one expression element
</para></refsect2>
- <refsect2><title><sgmltag>if</></title><para>
+ <refsect2><title><literal><if></literal></title><para>
This element takes three expression elements; if the value of the first is
true, it produces the value of the second, otherwise it produces the value
of the third.
</para></refsect2>
- <refsect2><title><sgmltag>alias</></title><para>
+ <refsect2><title><literal><alias></literal></title><para>
Alias elements provide a shorthand notation for the set of common match
operations needed to substitute one font family for another. They contain a
-<sgmltag>family</> element followed by optional <sgmltag>prefer</>, <sgmltag>accept</> and <sgmltag>default</>
-elements. Fonts matching the <sgmltag>family</> element are edited to prepend the
-list of <sgmltag>prefer</>ed families before the matching <sgmltag>family</>, append the
-<sgmltag>accept</>able familys after the matching <sgmltag>family</> and append the <sgmltag>default</>
+<literal><family></literal> element followed by optional <literal><prefer></literal>, <literal><accept></literal> and <literal><default></literal>
+elements. Fonts matching the <literal><family></literal> element are edited to prepend the
+list of <literal><prefer></literal>ed families before the matching <literal><family></literal>, append the
+<literal><accept></literal>able families after the matching <literal><family></literal> and append the <literal><default></literal>
families to the end of the family list.
</para></refsect2>
- <refsect2><title><sgmltag>family</></title><para>
+ <refsect2><title><literal><family></literal></title><para>
Holds a single font family name
</para></refsect2>
- <refsect2><title><sgmltag>prefer</>, <sgmltag>accept</>, <sgmltag>default</></title><para>
-These hold a list of <sgmltag>family</> elements to be used by the <sgmltag>alias</> element.
-<sgmltag>/article</>
+ <refsect2><title><literal><prefer></literal>, <literal><accept></literal>, <literal><default></literal></title><para>
+These hold a list of <literal><family></literal> elements to be used by the <literal><alias></literal> element.
</para></refsect2>
</refsect1>
<refsect1><title>EXAMPLE CONFIGURATION FILE</title>
</refsect1>
<refsect1><title>See Also</title>
<para>
-fc-cache(1), fc-match(1), fc-list(1)
+fc-cat(1), fc-cache(1), fc-list(1), fc-match(1), fc-query(1)
</para>
</refsect1>
<refsect1><title>Version</title>