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      3      1.1  mrg ><HEAD
      4      1.1  mrg ><TITLE
      5      1.1  mrg >FUNCTIONAL OVERVIEW</TITLE
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     45  1.1.1.2  mrg >&#60;&#60;&#60; Previous</A
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     59  1.1.1.2  mrg >Next &#62;&#62;&#62;</A
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     66      1.1  mrg ><DIV
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     68      1.1  mrg ><H1
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     70      1.1  mrg ><A
     71      1.1  mrg NAME="AEN19"
     72  1.1.1.2  mrg >FUNCTIONAL OVERVIEW</A
     73      1.1  mrg ></H1
     74      1.1  mrg ><P
     75      1.1  mrg >Fontconfig contains two essential modules, the configuration module which
     76      1.1  mrg builds an internal configuration from XML files and the matching module
     77      1.1  mrg which accepts font patterns and returns the nearest matching font.
     78      1.1  mrg   </P
     79      1.1  mrg ><DIV
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     81      1.1  mrg ><H2
     82      1.1  mrg CLASS="SECT2"
     83      1.1  mrg ><A
     84      1.1  mrg NAME="AEN22"
     85  1.1.1.2  mrg >FONT CONFIGURATION</A
     86      1.1  mrg ></H2
     87      1.1  mrg ><P
     88      1.1  mrg >The configuration module consists of the FcConfig datatype, libexpat and
     89  1.1.1.3  mrg FcConfigParse which walks over an XML tree and amends a configuration with
     90      1.1  mrg data found within.  From an external perspective, configuration of the
     91      1.1  mrg library consists of generating a valid XML tree and feeding that to
     92      1.1  mrg FcConfigParse.  The only other mechanism provided to applications for
     93      1.1  mrg changing the running configuration is to add fonts and directories to the
     94      1.1  mrg list of application-provided font files.  
     95      1.1  mrg     </P
     96      1.1  mrg ><P
     97      1.1  mrg >The intent is to make font configurations relatively static, and shared by
     98      1.1  mrg as many applications as possible.  It is hoped that this will lead to more
     99      1.1  mrg stable font selection when passing names from one application to another.
    100      1.1  mrg XML was chosen as a configuration file format because it provides a format
    101      1.1  mrg which is easy for external agents to edit while retaining the correct
    102      1.1  mrg structure and syntax.
    103      1.1  mrg     </P
    104      1.1  mrg ><P
    105      1.1  mrg >Font configuration is separate from font matching; applications needing to
    106      1.1  mrg do their own matching can access the available fonts from the library and
    107      1.1  mrg perform private matching.  The intent is to permit applications to pick and
    108      1.1  mrg choose appropriate functionality from the library instead of forcing them to
    109      1.1  mrg choose between this library and a private configuration mechanism.  The hope
    110      1.1  mrg is that this will ensure that configuration of fonts for all applications
    111      1.1  mrg can be centralized in one place.  Centralizing font configuration will
    112      1.1  mrg simplify and regularize font installation and customization.
    113      1.1  mrg     </P
    114      1.1  mrg ></DIV
    115      1.1  mrg ><DIV
    116      1.1  mrg CLASS="SECT2"
    117      1.1  mrg ><H2
    118      1.1  mrg CLASS="SECT2"
    119      1.1  mrg ><A
    120      1.1  mrg NAME="AEN27"
    121  1.1.1.2  mrg >FONT PROPERTIES</A
    122      1.1  mrg ></H2
    123      1.1  mrg ><P
    124      1.1  mrg >While font patterns may contain essentially any properties, there are some
    125      1.1  mrg well known properties with associated types.  Fontconfig uses some of these
    126      1.1  mrg properties for font matching and font completion.  Others are provided as a
    127  1.1.1.3  mrg convenience for the application's rendering mechanism.
    128      1.1  mrg     </P
    129  1.1.1.2  mrg ><TABLE
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    132  1.1.1.2  mrg WIDTH="100%"
    133  1.1.1.2  mrg ><TR
    134  1.1.1.2  mrg ><TD
    135      1.1  mrg ><PRE
    136      1.1  mrg CLASS="PROGRAMLISTING"
    137      1.1  mrg >                 Property Definitions
    138      1.1  mrg 
    139  1.1.1.3  mrg     Property       C Preprocessor Symbol  Type    Description
    140      1.1  mrg     ----------------------------------------------------
    141  1.1.1.3  mrg     family         FC_FAMILY              String  Font family names
    142  1.1.1.3  mrg     familylang     FC_FAMILYLANG          String  Language corresponding to
    143  1.1.1.3  mrg                                                   each family name
    144  1.1.1.3  mrg     style          FC_STYLE               String  Font style. Overrides weight
    145  1.1.1.3  mrg                                                   and slant
    146  1.1.1.3  mrg     stylelang      FC_STYLELANG           String  Language corresponding to
    147  1.1.1.3  mrg                                                   each style name
    148  1.1.1.3  mrg     fullname       FC_FULLNAME            String  Font face full name where
    149  1.1.1.3  mrg                                                   different from family and
    150  1.1.1.3  mrg                                                   family + style
    151  1.1.1.3  mrg     fullnamelang   FC_FULLNAMELANG        String  Language corresponding to
    152  1.1.1.3  mrg                                                   each fullname
    153  1.1.1.3  mrg     slant          FC_SLANT               Int     Italic, oblique or roman
    154  1.1.1.3  mrg     weight         FC_WEIGHT              Int     Light, medium, demibold,
    155  1.1.1.3  mrg                                                   bold or black
    156  1.1.1.3  mrg     size           FC_SIZE                Double  Point size
    157  1.1.1.3  mrg     width          FC_WIDTH               Int     Condensed, normal or expanded
    158  1.1.1.3  mrg     aspect         FC_ASPECT              Double  Stretches glyphs horizontally
    159  1.1.1.3  mrg                                                   before hinting
    160  1.1.1.3  mrg     pixelsize      FC_PIXEL_SIZE          Double  Pixel size
    161  1.1.1.3  mrg     spacing        FC_SPACING             Int     Proportional, dual-width,
    162  1.1.1.3  mrg                                                   monospace or charcell
    163  1.1.1.3  mrg     foundry        FC_FOUNDRY             String  Font foundry name
    164  1.1.1.3  mrg     antialias      FC_ANTIALIAS           Bool    Whether glyphs can be
    165  1.1.1.3  mrg                                                   antialiased
    166  1.1.1.3  mrg     hinting        FC_HINTING             Bool    Whether the rasterizer should
    167  1.1.1.3  mrg                                                   use hinting
    168  1.1.1.3  mrg     hintstyle      FC_HINT_STYLE          Int     Automatic hinting style
    169  1.1.1.3  mrg     verticallayout FC_VERTICAL_LAYOUT     Bool    Use vertical layout
    170  1.1.1.3  mrg     autohint       FC_AUTOHINT            Bool    Use autohinter instead of
    171  1.1.1.3  mrg                                                   normal hinter
    172  1.1.1.3  mrg     globaladvance  FC_GLOBAL_ADVANCE      Bool    Use font global advance data (deprecated)
    173  1.1.1.3  mrg     file           FC_FILE                String  The filename holding the font
    174  1.1.1.3  mrg     index          FC_INDEX               Int     The index of the font within
    175  1.1.1.3  mrg                                                   the file
    176  1.1.1.3  mrg     ftface         FC_FT_FACE             FT_Face Use the specified FreeType
    177  1.1.1.3  mrg                                                   face object
    178  1.1.1.3  mrg     rasterizer     FC_RASTERIZER          String  Which rasterizer is in use
    179  1.1.1.3  mrg     outline        FC_OUTLINE             Bool    Whether the glyphs are outlines
    180  1.1.1.3  mrg     scalable       FC_SCALABLE            Bool    Whether glyphs can be scaled
    181  1.1.1.3  mrg     scale          FC_SCALE               Double  Scale factor for point-&#62;pixel
    182  1.1.1.3  mrg                                                   conversions
    183  1.1.1.3  mrg     dpi            FC_DPI                 Double  Target dots per inch
    184  1.1.1.3  mrg     rgba           FC_RGBA                Int     unknown, rgb, bgr, vrgb,
    185  1.1.1.3  mrg                                                   vbgr, none - subpixel geometry
    186  1.1.1.3  mrg     lcdfilter      FC_LCD_FILTER          Int     Type of LCD filter
    187  1.1.1.3  mrg     minspace       FC_MINSPACE            Bool    Eliminate leading from line
    188  1.1.1.3  mrg                                                   spacing
    189  1.1.1.3  mrg     charset        FC_CHARSET             CharSet Unicode chars encoded by
    190  1.1.1.3  mrg                                                   the font
    191  1.1.1.3  mrg     lang           FC_LANG                LangSet Set of RFC-3066-style
    192  1.1.1.3  mrg                                                   languages this font supports
    193  1.1.1.3  mrg     fontversion    FC_FONTVERSION         Int     Version number of the font
    194  1.1.1.3  mrg     capability     FC_CAPABILITY          String  List of layout capabilities in
    195  1.1.1.3  mrg                                                   the font
    196  1.1.1.3  mrg     embolden       FC_EMBOLDEN            Bool    Rasterizer should
    197  1.1.1.3  mrg                                                   synthetically embolden the font
    198  1.1.1.4  mrg     fontfeatures   FC_FONT_FEATURES       String  List of extra feature tags in
    199  1.1.1.4  mrg                                                   OpenType to be enabled
    200  1.1.1.3  mrg     namelang       FC_NAMELANG            String  Language name to be used for the
    201  1.1.1.3  mrg                                                   default value of familylang,
    202  1.1.1.3  mrg                                                   stylelang and fullnamelang
    203  1.1.1.4  mrg     prgname        FC_PRGNAME             String  Name of the running program
    204  1.1.1.4  mrg     hash           FC_HASH                String  SHA256 hash value of the font data
    205  1.1.1.4  mrg                                                   with "sha256:" prefix.
    206  1.1.1.4  mrg     postscriptname FC_POSTSCRIPT_NAME     String  Font name in PostScript
    207      1.1  mrg     </PRE
    208  1.1.1.2  mrg ></TD
    209  1.1.1.2  mrg ></TR
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    249  1.1.1.2  mrg >Next &#62;&#62;&#62;</A
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    267      1.1  mrg >Datatypes</TD
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