1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2 <HTML 3 ><HEAD 4 ><TITLE 5 >FUNCTIONAL OVERVIEW</TITLE 6 ><META 7 NAME="GENERATOR" 8 CONTENT="Modular DocBook HTML Stylesheet Version 1.79"><LINK 9 REL="HOME" 10 HREF="t1.html"><LINK 11 REL="PREVIOUS" 12 HREF="t1.html"><LINK 13 REL="NEXT" 14 TITLE="Datatypes" 15 HREF="x31.html"></HEAD 16 ><BODY 17 CLASS="SECT1" 18 BGCOLOR="#FFFFFF" 19 TEXT="#000000" 20 LINK="#0000FF" 21 VLINK="#840084" 22 ALINK="#0000FF" 23 ><DIV 24 CLASS="NAVHEADER" 25 ><TABLE 26 SUMMARY="Header navigation table" 27 WIDTH="100%" 28 BORDER="0" 29 CELLPADDING="0" 30 CELLSPACING="0" 31 ><TR 32 ><TH 33 COLSPAN="3" 34 ALIGN="center" 35 ></TH 36 ></TR 37 ><TR 38 ><TD 39 WIDTH="10%" 40 ALIGN="left" 41 VALIGN="bottom" 42 ><A 43 HREF="t1.html" 44 ACCESSKEY="P" 45 ><<< Previous</A 46 ></TD 47 ><TD 48 WIDTH="80%" 49 ALIGN="center" 50 VALIGN="bottom" 51 ></TD 52 ><TD 53 WIDTH="10%" 54 ALIGN="right" 55 VALIGN="bottom" 56 ><A 57 HREF="x31.html" 58 ACCESSKEY="N" 59 >Next >>></A 60 ></TD 61 ></TR 62 ></TABLE 63 ><HR 64 ALIGN="LEFT" 65 WIDTH="100%"></DIV 66 ><DIV 67 CLASS="SECT1" 68 ><H1 69 CLASS="SECT1" 70 ><A 71 NAME="AEN19" 72 >FUNCTIONAL OVERVIEW</A 73 ></H1 74 ><P 75 >Fontconfig contains two essential modules, the configuration module which 76 builds an internal configuration from XML files and the matching module 77 which accepts font patterns and returns the nearest matching font. 78 </P 79 ><DIV 80 CLASS="SECT2" 81 ><H2 82 CLASS="SECT2" 83 ><A 84 NAME="AEN22" 85 >FONT CONFIGURATION</A 86 ></H2 87 ><P 88 >The configuration module consists of the FcConfig datatype, libexpat and 89 FcConfigParse which walks over an XML tree and amends a configuration with 90 data found within. From an external perspective, configuration of the 91 library consists of generating a valid XML tree and feeding that to 92 FcConfigParse. The only other mechanism provided to applications for 93 changing the running configuration is to add fonts and directories to the 94 list of application-provided font files. 95 </P 96 ><P 97 >The intent is to make font configurations relatively static, and shared by 98 as many applications as possible. It is hoped that this will lead to more 99 stable font selection when passing names from one application to another. 100 XML was chosen as a configuration file format because it provides a format 101 which is easy for external agents to edit while retaining the correct 102 structure and syntax. 103 </P 104 ><P 105 >Font configuration is separate from font matching; applications needing to 106 do their own matching can access the available fonts from the library and 107 perform private matching. The intent is to permit applications to pick and 108 choose appropriate functionality from the library instead of forcing them to 109 choose between this library and a private configuration mechanism. The hope 110 is that this will ensure that configuration of fonts for all applications 111 can be centralized in one place. Centralizing font configuration will 112 simplify and regularize font installation and customization. 113 </P 114 ></DIV 115 ><DIV 116 CLASS="SECT2" 117 ><H2 118 CLASS="SECT2" 119 ><A 120 NAME="AEN27" 121 >FONT PROPERTIES</A 122 ></H2 123 ><P 124 >While font patterns may contain essentially any properties, there are some 125 well known properties with associated types. Fontconfig uses some of these 126 properties for font matching and font completion. Others are provided as a 127 convenience for the application's rendering mechanism. 128 </P 129 ><TABLE 130 BORDER="0" 131 BGCOLOR="#E0E0E0" 132 WIDTH="100%" 133 ><TR 134 ><TD 135 ><PRE 136 CLASS="PROGRAMLISTING" 137 > Property Definitions 138 139 Property C Preprocessor Symbol Type Description 140 ---------------------------------------------------- 141 family FC_FAMILY String Font family names 142 familylang FC_FAMILYLANG String Language corresponding to 143 each family name 144 style FC_STYLE String Font style. Overrides weight 145 and slant 146 stylelang FC_STYLELANG String Language corresponding to 147 each style name 148 fullname FC_FULLNAME String Font face full name where 149 different from family and 150 family + style 151 fullnamelang FC_FULLNAMELANG String Language corresponding to 152 each fullname 153 slant FC_SLANT Int Italic, oblique or roman 154 weight FC_WEIGHT Int Light, medium, demibold, 155 bold or black 156 width FC_WIDTH Int Condensed, normal or expanded 157 size FC_SIZE Double Point size 158 aspect FC_ASPECT Double Stretches glyphs horizontally 159 before hinting 160 pixelsize FC_PIXEL_SIZE Double Pixel size 161 spacing FC_SPACING Int Proportional, dual-width, 162 monospace or charcell 163 foundry FC_FOUNDRY String Font foundry name 164 antialias FC_ANTIALIAS Bool Whether glyphs can be 165 antialiased 166 hintstyle FC_HINT_STYLE Int Automatic hinting style 167 hinting FC_HINTING Bool Whether the rasterizer should 168 use hinting 169 verticallayout FC_VERTICAL_LAYOUT Bool Use vertical layout 170 autohint FC_AUTOHINT Bool Use autohinter instead of 171 normal hinter 172 globaladvance FC_GLOBAL_ADVANCE Bool Use font global advance data (deprecated) 173 file FC_FILE String The filename holding the font 174 relative to the config's sysroot 175 index FC_INDEX Int The index of the font within 176 the file 177 ftface FC_FT_FACE FT_Face Use the specified FreeType 178 face object 179 rasterizer FC_RASTERIZER String Which rasterizer is in use (deprecated) 180 outline FC_OUTLINE Bool Whether the glyphs are outlines 181 scalable FC_SCALABLE Bool Whether the glyphs are outlines or have color 182 dpi FC_DPI Double Target dots per inch 183 rgba FC_RGBA Int unknown, rgb, bgr, vrgb, 184 vbgr, none - subpixel geometry 185 scale FC_SCALE Double Scale factor for point->pixel 186 conversions (deprecated) 187 minspace FC_MINSPACE Bool Eliminate leading from line 188 spacing 189 matrix FC_MATRIX Matrix Hold an affine transformation 190 charset FC_CHARSET CharSet Unicode chars encoded by 191 the font 192 lang FC_LANG LangSet Set of RFC-3066-style 193 languages this font supports 194 fontversion FC_FONTVERSION Int Version number of the font 195 capability FC_CAPABILITY String List of layout capabilities in 196 the font 197 fontformat FC_FONTFORMAT String String name of the font format 198 embolden FC_EMBOLDEN Bool Rasterizer should 199 synthetically embolden the font 200 embeddedbitmap FC_EMBEDDED_BITMAP Bool Use the embedded bitmap instead 201 of the outline 202 decorative FC_DECORATIVE Bool Whether the style is a decorative 203 variant 204 lcdfilter FC_LCD_FILTER Int Type of LCD filter 205 namelang FC_NAMELANG String Language name to be used for the 206 default value of familylang, 207 stylelang and fullnamelang 208 fontfeatures FC_FONT_FEATURES String List of extra feature tags in 209 OpenType to be enabled 210 prgname FC_PRGNAME String Name of the running program 211 hash FC_HASH String SHA256 hash value of the font data 212 with "sha256:" prefix (deprecated) 213 postscriptname FC_POSTSCRIPT_NAME String Font name in PostScript 214 color FC_COLOR Bool Whether any glyphs have color 215 symbol FC_SYMBOL Bool Whether font uses MS symbol-font encoding 216 fontvariations FC_FONT_VARIATIONS String comma-separated string of axes in variable font 217 variable FC_VARIABLE Bool Whether font is Variable Font 218 fonthashint FC_FONT_HAS_HINT Bool Whether font has hinting 219 order FC_ORDER Int Order number of the font 220 desktop FC_DESKTOP_NAME String Current desktop name 221 namedinstance FC_NAMED_INSTANCE Bool Whether font is a named instance 222 fontwarapper FC_FONT_WRAPPER String The font wrapper format 223 </PRE 224 ></TD 225 ></TR 226 ></TABLE 227 ></DIV 228 ></DIV 229 ><DIV 230 CLASS="NAVFOOTER" 231 ><HR 232 ALIGN="LEFT" 233 WIDTH="100%"><TABLE 234 SUMMARY="Footer navigation table" 235 WIDTH="100%" 236 BORDER="0" 237 CELLPADDING="0" 238 CELLSPACING="0" 239 ><TR 240 ><TD 241 WIDTH="33%" 242 ALIGN="left" 243 VALIGN="top" 244 ><A 245 HREF="t1.html" 246 ACCESSKEY="P" 247 ><<< Previous</A 248 ></TD 249 ><TD 250 WIDTH="34%" 251 ALIGN="center" 252 VALIGN="top" 253 ><A 254 HREF="t1.html" 255 ACCESSKEY="H" 256 >Home</A 257 ></TD 258 ><TD 259 WIDTH="33%" 260 ALIGN="right" 261 VALIGN="top" 262 ><A 263 HREF="x31.html" 264 ACCESSKEY="N" 265 >Next >>></A 266 ></TD 267 ></TR 268 ><TR 269 ><TD 270 WIDTH="33%" 271 ALIGN="left" 272 VALIGN="top" 273 ></TD 274 ><TD 275 WIDTH="34%" 276 ALIGN="center" 277 VALIGN="top" 278 > </TD 279 ><TD 280 WIDTH="33%" 281 ALIGN="right" 282 VALIGN="top" 283 >Datatypes</TD 284 ></TR 285 ></TABLE 286 ></DIV 287 ></BODY 288 ></HTML 289 >
Indexes created Tue Oct 27 00:25:24 UTC 2026