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      1 /***************************************************************************/
      2 /*                                                                         */
      3 /*  tttables.h                                                             */
      4 /*                                                                         */
      5 /*    Basic SFNT/TrueType tables definitions and interface                 */
      6 /*    (specification only).                                                */
      7 /*                                                                         */
      8 /*  Copyright 1996-2005, 2008-2011 by                                      */
      9 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
     10 /*                                                                         */
     11 /*  This file is part of the FreeType project, and may only be used,       */
     12 /*  modified, and distributed under the terms of the FreeType project      */
     13 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
     14 /*  this file you indicate that you have read the license and              */
     15 /*  understand and accept it fully.                                        */
     16 /*                                                                         */
     17 /***************************************************************************/
     18 
     19 
     20 #ifndef __TTTABLES_H__
     21 #define __TTTABLES_H__
     22 
     23 
     24 #include <ft2build.h>
     25 #include FT_FREETYPE_H
     26 
     27 #ifdef FREETYPE_H
     28 #error "freetype.h of FreeType 1 has been loaded!"
     29 #error "Please fix the directory search order for header files"
     30 #error "so that freetype.h of FreeType 2 is found first."
     31 #endif
     32 
     33 
     34 FT_BEGIN_HEADER
     35 
     36   /*************************************************************************/
     37   /*                                                                       */
     38   /* <Section>                                                             */
     39   /*    truetype_tables                                                    */
     40   /*                                                                       */
     41   /* <Title>                                                               */
     42   /*    TrueType Tables                                                    */
     43   /*                                                                       */
     44   /* <Abstract>                                                            */
     45   /*    TrueType specific table types and functions.                       */
     46   /*                                                                       */
     47   /* <Description>                                                         */
     48   /*    This section contains the definition of TrueType-specific tables   */
     49   /*    as well as some routines used to access and process them.          */
     50   /*                                                                       */
     51   /*************************************************************************/
     52 
     53 
     54   /*************************************************************************/
     55   /*                                                                       */
     56   /* <Struct>                                                              */
     57   /*    TT_Header                                                          */
     58   /*                                                                       */
     59   /* <Description>                                                         */
     60   /*    A structure used to model a TrueType font header table.  All       */
     61   /*    fields follow the TrueType specification.                          */
     62   /*                                                                       */
     63   typedef struct  TT_Header_
     64   {
     65     FT_Fixed   Table_Version;
     66     FT_Fixed   Font_Revision;
     67 
     68     FT_Long    CheckSum_Adjust;
     69     FT_Long    Magic_Number;
     70 
     71     FT_UShort  Flags;
     72     FT_UShort  Units_Per_EM;
     73 
     74     FT_Long    Created [2];
     75     FT_Long    Modified[2];
     76 
     77     FT_Short   xMin;
     78     FT_Short   yMin;
     79     FT_Short   xMax;
     80     FT_Short   yMax;
     81 
     82     FT_UShort  Mac_Style;
     83     FT_UShort  Lowest_Rec_PPEM;
     84 
     85     FT_Short   Font_Direction;
     86     FT_Short   Index_To_Loc_Format;
     87     FT_Short   Glyph_Data_Format;
     88 
     89   } TT_Header;
     90 
     91 
     92   /*************************************************************************/
     93   /*                                                                       */
     94   /* <Struct>                                                              */
     95   /*    TT_HoriHeader                                                      */
     96   /*                                                                       */
     97   /* <Description>                                                         */
     98   /*    A structure used to model a TrueType horizontal header, the `hhea' */
     99   /*    table, as well as the corresponding horizontal metrics table,      */
    100   /*    i.e., the `hmtx' table.                                            */
    101   /*                                                                       */
    102   /* <Fields>                                                              */
    103   /*    Version                :: The table version.                       */
    104   /*                                                                       */
    105   /*    Ascender               :: The font's ascender, i.e., the distance  */
    106   /*                              from the baseline to the top-most of all */
    107   /*                              glyph points found in the font.          */
    108   /*                                                                       */
    109   /*                              This value is invalid in many fonts, as  */
    110   /*                              it is usually set by the font designer,  */
    111   /*                              and often reflects only a portion of the */
    112   /*                              glyphs found in the font (maybe ASCII).  */
    113   /*                                                                       */
    114   /*                              You should use the `sTypoAscender' field */
    115   /*                              of the OS/2 table instead if you want    */
    116   /*                              the correct one.                         */
    117   /*                                                                       */
    118   /*    Descender              :: The font's descender, i.e., the distance */
    119   /*                              from the baseline to the bottom-most of  */
    120   /*                              all glyph points found in the font.  It  */
    121   /*                              is negative.                             */
    122   /*                                                                       */
    123   /*                              This value is invalid in many fonts, as  */
    124   /*                              it is usually set by the font designer,  */
    125   /*                              and often reflects only a portion of the */
    126   /*                              glyphs found in the font (maybe ASCII).  */
    127   /*                                                                       */
    128   /*                              You should use the `sTypoDescender'      */
    129   /*                              field of the OS/2 table instead if you   */
    130   /*                              want the correct one.                    */
    131   /*                                                                       */
    132   /*    Line_Gap               :: The font's line gap, i.e., the distance  */
    133   /*                              to add to the ascender and descender to  */
    134   /*                              get the BTB, i.e., the                   */
    135   /*                              baseline-to-baseline distance for the    */
    136   /*                              font.                                    */
    137   /*                                                                       */
    138   /*    advance_Width_Max      :: This field is the maximum of all advance */
    139   /*                              widths found in the font.  It can be     */
    140   /*                              used to compute the maximum width of an  */
    141   /*                              arbitrary string of text.                */
    142   /*                                                                       */
    143   /*    min_Left_Side_Bearing  :: The minimum left side bearing of all     */
    144   /*                              glyphs within the font.                  */
    145   /*                                                                       */
    146   /*    min_Right_Side_Bearing :: The minimum right side bearing of all    */
    147   /*                              glyphs within the font.                  */
    148   /*                                                                       */
    149   /*    xMax_Extent            :: The maximum horizontal extent (i.e., the */
    150   /*                              `width' of a glyph's bounding box) for   */
    151   /*                              all glyphs in the font.                  */
    152   /*                                                                       */
    153   /*    caret_Slope_Rise       :: The rise coefficient of the cursor's     */
    154   /*                              slope of the cursor (slope=rise/run).    */
    155   /*                                                                       */
    156   /*    caret_Slope_Run        :: The run coefficient of the cursor's      */
    157   /*                              slope.                                   */
    158   /*                                                                       */
    159   /*    Reserved               :: 8~reserved bytes.                        */
    160   /*                                                                       */
    161   /*    metric_Data_Format     :: Always~0.                                */
    162   /*                                                                       */
    163   /*    number_Of_HMetrics     :: Number of HMetrics entries in the `hmtx' */
    164   /*                              table -- this value can be smaller than  */
    165   /*                              the total number of glyphs in the font.  */
    166   /*                                                                       */
    167   /*    long_metrics           :: A pointer into the `hmtx' table.         */
    168   /*                                                                       */
    169   /*    short_metrics          :: A pointer into the `hmtx' table.         */
    170   /*                                                                       */
    171   /* <Note>                                                                */
    172   /*    IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should   */
    173   /*               be identical except for the names of their fields which */
    174   /*               are different.                                          */
    175   /*                                                                       */
    176   /*               This ensures that a single function in the `ttload'     */
    177   /*               module is able to read both the horizontal and vertical */
    178   /*               headers.                                                */
    179   /*                                                                       */
    180   typedef struct  TT_HoriHeader_
    181   {
    182     FT_Fixed   Version;
    183     FT_Short   Ascender;
    184     FT_Short   Descender;
    185     FT_Short   Line_Gap;
    186 
    187     FT_UShort  advance_Width_Max;      /* advance width maximum */
    188 
    189     FT_Short   min_Left_Side_Bearing;  /* minimum left-sb       */
    190     FT_Short   min_Right_Side_Bearing; /* minimum right-sb      */
    191     FT_Short   xMax_Extent;            /* xmax extents          */
    192     FT_Short   caret_Slope_Rise;
    193     FT_Short   caret_Slope_Run;
    194     FT_Short   caret_Offset;
    195 
    196     FT_Short   Reserved[4];
    197 
    198     FT_Short   metric_Data_Format;
    199     FT_UShort  number_Of_HMetrics;
    200 
    201     /* The following fields are not defined by the TrueType specification */
    202     /* but they are used to connect the metrics header to the relevant    */
    203     /* `HMTX' table.                                                      */
    204 
    205     void*      long_metrics;
    206     void*      short_metrics;
    207 
    208   } TT_HoriHeader;
    209 
    210 
    211   /*************************************************************************/
    212   /*                                                                       */
    213   /* <Struct>                                                              */
    214   /*    TT_VertHeader                                                      */
    215   /*                                                                       */
    216   /* <Description>                                                         */
    217   /*    A structure used to model a TrueType vertical header, the `vhea'   */
    218   /*    table, as well as the corresponding vertical metrics table, i.e.,  */
    219   /*    the `vmtx' table.                                                  */
    220   /*                                                                       */
    221   /* <Fields>                                                              */
    222   /*    Version                 :: The table version.                      */
    223   /*                                                                       */
    224   /*    Ascender                :: The font's ascender, i.e., the distance */
    225   /*                               from the baseline to the top-most of    */
    226   /*                               all glyph points found in the font.     */
    227   /*                                                                       */
    228   /*                               This value is invalid in many fonts, as */
    229   /*                               it is usually set by the font designer, */
    230   /*                               and often reflects only a portion of    */
    231   /*                               the glyphs found in the font (maybe     */
    232   /*                               ASCII).                                 */
    233   /*                                                                       */
    234   /*                               You should use the `sTypoAscender'      */
    235   /*                               field of the OS/2 table instead if you  */
    236   /*                               want the correct one.                   */
    237   /*                                                                       */
    238   /*    Descender               :: The font's descender, i.e., the         */
    239   /*                               distance from the baseline to the       */
    240   /*                               bottom-most of all glyph points found   */
    241   /*                               in the font.  It is negative.           */
    242   /*                                                                       */
    243   /*                               This value is invalid in many fonts, as */
    244   /*                               it is usually set by the font designer, */
    245   /*                               and often reflects only a portion of    */
    246   /*                               the glyphs found in the font (maybe     */
    247   /*                               ASCII).                                 */
    248   /*                                                                       */
    249   /*                               You should use the `sTypoDescender'     */
    250   /*                               field of the OS/2 table instead if you  */
    251   /*                               want the correct one.                   */
    252   /*                                                                       */
    253   /*    Line_Gap                :: The font's line gap, i.e., the distance */
    254   /*                               to add to the ascender and descender to */
    255   /*                               get the BTB, i.e., the                  */
    256   /*                               baseline-to-baseline distance for the   */
    257   /*                               font.                                   */
    258   /*                                                                       */
    259   /*    advance_Height_Max      :: This field is the maximum of all        */
    260   /*                               advance heights found in the font.  It  */
    261   /*                               can be used to compute the maximum      */
    262   /*                               height of an arbitrary string of text.  */
    263   /*                                                                       */
    264   /*    min_Top_Side_Bearing    :: The minimum top side bearing of all     */
    265   /*                               glyphs within the font.                 */
    266   /*                                                                       */
    267   /*    min_Bottom_Side_Bearing :: The minimum bottom side bearing of all  */
    268   /*                               glyphs within the font.                 */
    269   /*                                                                       */
    270   /*    yMax_Extent             :: The maximum vertical extent (i.e., the  */
    271   /*                               `height' of a glyph's bounding box) for */
    272   /*                               all glyphs in the font.                 */
    273   /*                                                                       */
    274   /*    caret_Slope_Rise        :: The rise coefficient of the cursor's    */
    275   /*                               slope of the cursor (slope=rise/run).   */
    276   /*                                                                       */
    277   /*    caret_Slope_Run         :: The run coefficient of the cursor's     */
    278   /*                               slope.                                  */
    279   /*                                                                       */
    280   /*    caret_Offset            :: The cursor's offset for slanted fonts.  */
    281   /*                               This value is `reserved' in vmtx        */
    282   /*                               version 1.0.                            */
    283   /*                                                                       */
    284   /*    Reserved                :: 8~reserved bytes.                       */
    285   /*                                                                       */
    286   /*    metric_Data_Format      :: Always~0.                               */
    287   /*                                                                       */
    288   /*    number_Of_HMetrics      :: Number of VMetrics entries in the       */
    289   /*                               `vmtx' table -- this value can be       */
    290   /*                               smaller than the total number of glyphs */
    291   /*                               in the font.                            */
    292   /*                                                                       */
    293   /*    long_metrics           :: A pointer into the `vmtx' table.         */
    294   /*                                                                       */
    295   /*    short_metrics          :: A pointer into the `vmtx' table.         */
    296   /*                                                                       */
    297   /* <Note>                                                                */
    298   /*    IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should   */
    299   /*               be identical except for the names of their fields which */
    300   /*               are different.                                          */
    301   /*                                                                       */
    302   /*               This ensures that a single function in the `ttload'     */
    303   /*               module is able to read both the horizontal and vertical */
    304   /*               headers.                                                */
    305   /*                                                                       */
    306   typedef struct  TT_VertHeader_
    307   {
    308     FT_Fixed   Version;
    309     FT_Short   Ascender;
    310     FT_Short   Descender;
    311     FT_Short   Line_Gap;
    312 
    313     FT_UShort  advance_Height_Max;      /* advance height maximum */
    314 
    315     FT_Short   min_Top_Side_Bearing;    /* minimum left-sb or top-sb       */
    316     FT_Short   min_Bottom_Side_Bearing; /* minimum right-sb or bottom-sb   */
    317     FT_Short   yMax_Extent;             /* xmax or ymax extents            */
    318     FT_Short   caret_Slope_Rise;
    319     FT_Short   caret_Slope_Run;
    320     FT_Short   caret_Offset;
    321 
    322     FT_Short   Reserved[4];
    323 
    324     FT_Short   metric_Data_Format;
    325     FT_UShort  number_Of_VMetrics;
    326 
    327     /* The following fields are not defined by the TrueType specification */
    328     /* but they're used to connect the metrics header to the relevant     */
    329     /* `HMTX' or `VMTX' table.                                            */
    330 
    331     void*      long_metrics;
    332     void*      short_metrics;
    333 
    334   } TT_VertHeader;
    335 
    336 
    337   /*************************************************************************/
    338   /*                                                                       */
    339   /* <Struct>                                                              */
    340   /*    TT_OS2                                                             */
    341   /*                                                                       */
    342   /* <Description>                                                         */
    343   /*    A structure used to model a TrueType OS/2 table. This is the long  */
    344   /*    table version.  All fields comply to the TrueType specification.   */
    345   /*                                                                       */
    346   /*    Note that we now support old Mac fonts which do not include an     */
    347   /*    OS/2 table.  In this case, the `version' field is always set to    */
    348   /*    0xFFFF.                                                            */
    349   /*                                                                       */
    350   typedef struct  TT_OS2_
    351   {
    352     FT_UShort  version;                /* 0x0001 - more or 0xFFFF */
    353     FT_Short   xAvgCharWidth;
    354     FT_UShort  usWeightClass;
    355     FT_UShort  usWidthClass;
    356     FT_Short   fsType;
    357     FT_Short   ySubscriptXSize;
    358     FT_Short   ySubscriptYSize;
    359     FT_Short   ySubscriptXOffset;
    360     FT_Short   ySubscriptYOffset;
    361     FT_Short   ySuperscriptXSize;
    362     FT_Short   ySuperscriptYSize;
    363     FT_Short   ySuperscriptXOffset;
    364     FT_Short   ySuperscriptYOffset;
    365     FT_Short   yStrikeoutSize;
    366     FT_Short   yStrikeoutPosition;
    367     FT_Short   sFamilyClass;
    368 
    369     FT_Byte    panose[10];
    370 
    371     FT_ULong   ulUnicodeRange1;        /* Bits 0-31   */
    372     FT_ULong   ulUnicodeRange2;        /* Bits 32-63  */
    373     FT_ULong   ulUnicodeRange3;        /* Bits 64-95  */
    374     FT_ULong   ulUnicodeRange4;        /* Bits 96-127 */
    375 
    376     FT_Char    achVendID[4];
    377 
    378     FT_UShort  fsSelection;
    379     FT_UShort  usFirstCharIndex;
    380     FT_UShort  usLastCharIndex;
    381     FT_Short   sTypoAscender;
    382     FT_Short   sTypoDescender;
    383     FT_Short   sTypoLineGap;
    384     FT_UShort  usWinAscent;
    385     FT_UShort  usWinDescent;
    386 
    387     /* only version 1 tables: */
    388 
    389     FT_ULong   ulCodePageRange1;       /* Bits 0-31   */
    390     FT_ULong   ulCodePageRange2;       /* Bits 32-63  */
    391 
    392     /* only version 2 tables: */
    393 
    394     FT_Short   sxHeight;
    395     FT_Short   sCapHeight;
    396     FT_UShort  usDefaultChar;
    397     FT_UShort  usBreakChar;
    398     FT_UShort  usMaxContext;
    399 
    400   } TT_OS2;
    401 
    402 
    403   /*************************************************************************/
    404   /*                                                                       */
    405   /* <Struct>                                                              */
    406   /*    TT_Postscript                                                      */
    407   /*                                                                       */
    408   /* <Description>                                                         */
    409   /*    A structure used to model a TrueType PostScript table.  All fields */
    410   /*    comply to the TrueType specification.  This structure does not     */
    411   /*    reference the PostScript glyph names, which can be nevertheless    */
    412   /*    accessed with the `ttpost' module.                                 */
    413   /*                                                                       */
    414   typedef struct  TT_Postscript_
    415   {
    416     FT_Fixed  FormatType;
    417     FT_Fixed  italicAngle;
    418     FT_Short  underlinePosition;
    419     FT_Short  underlineThickness;
    420     FT_ULong  isFixedPitch;
    421     FT_ULong  minMemType42;
    422     FT_ULong  maxMemType42;
    423     FT_ULong  minMemType1;
    424     FT_ULong  maxMemType1;
    425 
    426     /* Glyph names follow in the file, but we don't   */
    427     /* load them by default.  See the ttpost.c file.  */
    428 
    429   } TT_Postscript;
    430 
    431 
    432   /*************************************************************************/
    433   /*                                                                       */
    434   /* <Struct>                                                              */
    435   /*    TT_PCLT                                                            */
    436   /*                                                                       */
    437   /* <Description>                                                         */
    438   /*    A structure used to model a TrueType PCLT table.  All fields       */
    439   /*    comply to the TrueType specification.                              */
    440   /*                                                                       */
    441   typedef struct  TT_PCLT_
    442   {
    443     FT_Fixed   Version;
    444     FT_ULong   FontNumber;
    445     FT_UShort  Pitch;
    446     FT_UShort  xHeight;
    447     FT_UShort  Style;
    448     FT_UShort  TypeFamily;
    449     FT_UShort  CapHeight;
    450     FT_UShort  SymbolSet;
    451     FT_Char    TypeFace[16];
    452     FT_Char    CharacterComplement[8];
    453     FT_Char    FileName[6];
    454     FT_Char    StrokeWeight;
    455     FT_Char    WidthType;
    456     FT_Byte    SerifStyle;
    457     FT_Byte    Reserved;
    458 
    459   } TT_PCLT;
    460 
    461 
    462   /*************************************************************************/
    463   /*                                                                       */
    464   /* <Struct>                                                              */
    465   /*    TT_MaxProfile                                                      */
    466   /*                                                                       */
    467   /* <Description>                                                         */
    468   /*    The maximum profile is a table containing many max values which    */
    469   /*    can be used to pre-allocate arrays.  This ensures that no memory   */
    470   /*    allocation occurs during a glyph load.                             */
    471   /*                                                                       */
    472   /* <Fields>                                                              */
    473   /*    version               :: The version number.                       */
    474   /*                                                                       */
    475   /*    numGlyphs             :: The number of glyphs in this TrueType     */
    476   /*                             font.                                     */
    477   /*                                                                       */
    478   /*    maxPoints             :: The maximum number of points in a         */
    479   /*                             non-composite TrueType glyph.  See also   */
    480   /*                             the structure element                     */
    481   /*                             `maxCompositePoints'.                     */
    482   /*                                                                       */
    483   /*    maxContours           :: The maximum number of contours in a       */
    484   /*                             non-composite TrueType glyph.  See also   */
    485   /*                             the structure element                     */
    486   /*                             `maxCompositeContours'.                   */
    487   /*                                                                       */
    488   /*    maxCompositePoints    :: The maximum number of points in a         */
    489   /*                             composite TrueType glyph.  See also the   */
    490   /*                             structure element `maxPoints'.            */
    491   /*                                                                       */
    492   /*    maxCompositeContours  :: The maximum number of contours in a       */
    493   /*                             composite TrueType glyph.  See also the   */
    494   /*                             structure element `maxContours'.          */
    495   /*                                                                       */
    496   /*    maxZones              :: The maximum number of zones used for      */
    497   /*                             glyph hinting.                            */
    498   /*                                                                       */
    499   /*    maxTwilightPoints     :: The maximum number of points in the       */
    500   /*                             twilight zone used for glyph hinting.     */
    501   /*                                                                       */
    502   /*    maxStorage            :: The maximum number of elements in the     */
    503   /*                             storage area used for glyph hinting.      */
    504   /*                                                                       */
    505   /*    maxFunctionDefs       :: The maximum number of function            */
    506   /*                             definitions in the TrueType bytecode for  */
    507   /*                             this font.                                */
    508   /*                                                                       */
    509   /*    maxInstructionDefs    :: The maximum number of instruction         */
    510   /*                             definitions in the TrueType bytecode for  */
    511   /*                             this font.                                */
    512   /*                                                                       */
    513   /*    maxStackElements      :: The maximum number of stack elements used */
    514   /*                             during bytecode interpretation.           */
    515   /*                                                                       */
    516   /*    maxSizeOfInstructions :: The maximum number of TrueType opcodes    */
    517   /*                             used for glyph hinting.                   */
    518   /*                                                                       */
    519   /*    maxComponentElements  :: The maximum number of simple (i.e., non-  */
    520   /*                             composite) glyphs in a composite glyph.   */
    521   /*                                                                       */
    522   /*    maxComponentDepth     :: The maximum nesting depth of composite    */
    523   /*                             glyphs.                                   */
    524   /*                                                                       */
    525   /* <Note>                                                                */
    526   /*    This structure is only used during font loading.                   */
    527   /*                                                                       */
    528   typedef struct  TT_MaxProfile_
    529   {
    530     FT_Fixed   version;
    531     FT_UShort  numGlyphs;
    532     FT_UShort  maxPoints;
    533     FT_UShort  maxContours;
    534     FT_UShort  maxCompositePoints;
    535     FT_UShort  maxCompositeContours;
    536     FT_UShort  maxZones;
    537     FT_UShort  maxTwilightPoints;
    538     FT_UShort  maxStorage;
    539     FT_UShort  maxFunctionDefs;
    540     FT_UShort  maxInstructionDefs;
    541     FT_UShort  maxStackElements;
    542     FT_UShort  maxSizeOfInstructions;
    543     FT_UShort  maxComponentElements;
    544     FT_UShort  maxComponentDepth;
    545 
    546   } TT_MaxProfile;
    547 
    548 
    549   /*************************************************************************/
    550   /*                                                                       */
    551   /* <Enum>                                                                */
    552   /*    FT_Sfnt_Tag                                                        */
    553   /*                                                                       */
    554   /* <Description>                                                         */
    555   /*    An enumeration used to specify the index of an SFNT table.         */
    556   /*    Used in the @FT_Get_Sfnt_Table API function.                       */
    557   /*                                                                       */
    558   typedef enum  FT_Sfnt_Tag_
    559   {
    560     ft_sfnt_head = 0,    /* TT_Header     */
    561     ft_sfnt_maxp = 1,    /* TT_MaxProfile */
    562     ft_sfnt_os2  = 2,    /* TT_OS2        */
    563     ft_sfnt_hhea = 3,    /* TT_HoriHeader */
    564     ft_sfnt_vhea = 4,    /* TT_VertHeader */
    565     ft_sfnt_post = 5,    /* TT_Postscript */
    566     ft_sfnt_pclt = 6,    /* TT_PCLT       */
    567 
    568     sfnt_max   /* internal end mark */
    569 
    570   } FT_Sfnt_Tag;
    571 
    572   /* */
    573 
    574 
    575   /*************************************************************************/
    576   /*                                                                       */
    577   /* <Function>                                                            */
    578   /*    FT_Get_Sfnt_Table                                                  */
    579   /*                                                                       */
    580   /* <Description>                                                         */
    581   /*    Return a pointer to a given SFNT table within a face.              */
    582   /*                                                                       */
    583   /* <Input>                                                               */
    584   /*    face :: A handle to the source.                                    */
    585   /*                                                                       */
    586   /*    tag  :: The index of the SFNT table.                               */
    587   /*                                                                       */
    588   /* <Return>                                                              */
    589   /*    A type-less pointer to the table.  This will be~0 in case of       */
    590   /*    error, or if the corresponding table was not found *OR* loaded     */
    591   /*    from the file.                                                     */
    592   /*                                                                       */
    593   /*    Use a typecast according to `tag' to access the structure          */
    594   /*    elements.                                                          */
    595   /*                                                                       */
    596   /* <Note>                                                                */
    597   /*    The table is owned by the face object and disappears with it.      */
    598   /*                                                                       */
    599   /*    This function is only useful to access SFNT tables that are loaded */
    600   /*    by the sfnt, truetype, and opentype drivers.  See @FT_Sfnt_Tag for */
    601   /*    a list.                                                            */
    602   /*                                                                       */
    603   FT_EXPORT( void* )
    604   FT_Get_Sfnt_Table( FT_Face      face,
    605                      FT_Sfnt_Tag  tag );
    606 
    607 
    608  /**************************************************************************
    609   *
    610   * @function:
    611   *   FT_Load_Sfnt_Table
    612   *
    613   * @description:
    614   *   Load any font table into client memory.
    615   *
    616   * @input:
    617   *   face ::
    618   *     A handle to the source face.
    619   *
    620   *   tag ::
    621   *     The four-byte tag of the table to load.  Use the value~0 if you want
    622   *     to access the whole font file.  Otherwise, you can use one of the
    623   *     definitions found in the @FT_TRUETYPE_TAGS_H file, or forge a new
    624   *     one with @FT_MAKE_TAG.
    625   *
    626   *   offset ::
    627   *     The starting offset in the table (or file if tag == 0).
    628   *
    629   * @output:
    630   *   buffer ::
    631   *     The target buffer address.  The client must ensure that the memory
    632   *     array is big enough to hold the data.
    633   *
    634   * @inout:
    635   *   length ::
    636   *     If the `length' parameter is NULL, then try to load the whole table.
    637   *     Return an error code if it fails.
    638   *
    639   *     Else, if `*length' is~0, exit immediately while returning the
    640   *     table's (or file) full size in it.
    641   *
    642   *     Else the number of bytes to read from the table or file, from the
    643   *     starting offset.
    644   *
    645   * @return:
    646   *   FreeType error code.  0~means success.
    647   *
    648   * @note:
    649   *   If you need to determine the table's length you should first call this
    650   *   function with `*length' set to~0, as in the following example:
    651   *
    652   *     {
    653   *       FT_ULong  length = 0;
    654   *
    655   *
    656   *       error = FT_Load_Sfnt_Table( face, tag, 0, NULL, &length );
    657   *       if ( error ) { ... table does not exist ... }
    658   *
    659   *       buffer = malloc( length );
    660   *       if ( buffer == NULL ) { ... not enough memory ... }
    661   *
    662   *       error = FT_Load_Sfnt_Table( face, tag, 0, buffer, &length );
    663   *       if ( error ) { ... could not load table ... }
    664   *     }
    665   */
    666   FT_EXPORT( FT_Error )
    667   FT_Load_Sfnt_Table( FT_Face    face,
    668                       FT_ULong   tag,
    669                       FT_Long    offset,
    670                       FT_Byte*   buffer,
    671                       FT_ULong*  length );
    672 
    673 
    674  /**************************************************************************
    675   *
    676   * @function:
    677   *   FT_Sfnt_Table_Info
    678   *
    679   * @description:
    680   *   Return information on an SFNT table.
    681   *
    682   * @input:
    683   *   face ::
    684   *     A handle to the source face.
    685   *
    686   *   table_index ::
    687   *     The index of an SFNT table.  The function returns
    688   *     FT_Err_Table_Missing for an invalid value.
    689   *
    690   * @inout:
    691   *   tag ::
    692   *     The name tag of the SFNT table.  If the value is NULL, `table_index'
    693   *     is ignored, and `length' returns the number of SFNT tables in the
    694   *     font.
    695   *
    696   * @output:
    697   *   length ::
    698   *     The length of the SFNT table (or the number of SFNT tables, depending
    699   *     on `tag').
    700   *
    701   * @return:
    702   *   FreeType error code.  0~means success.
    703   *
    704   * @note:
    705   *   SFNT tables with length zero are treated as missing.
    706   *
    707   */
    708   FT_EXPORT( FT_Error )
    709   FT_Sfnt_Table_Info( FT_Face    face,
    710                       FT_UInt    table_index,
    711                       FT_ULong  *tag,
    712                       FT_ULong  *length );
    713 
    714 
    715   /*************************************************************************/
    716   /*                                                                       */
    717   /* <Function>                                                            */
    718   /*    FT_Get_CMap_Language_ID                                            */
    719   /*                                                                       */
    720   /* <Description>                                                         */
    721   /*    Return TrueType/sfnt specific cmap language ID.  Definitions of    */
    722   /*    language ID values are in `freetype/ttnameid.h'.                   */
    723   /*                                                                       */
    724   /* <Input>                                                               */
    725   /*    charmap ::                                                         */
    726   /*      The target charmap.                                              */
    727   /*                                                                       */
    728   /* <Return>                                                              */
    729   /*    The language ID of `charmap'.  If `charmap' doesn't belong to a    */
    730   /*    TrueType/sfnt face, just return~0 as the default value.            */
    731   /*                                                                       */
    732   FT_EXPORT( FT_ULong )
    733   FT_Get_CMap_Language_ID( FT_CharMap  charmap );
    734 
    735 
    736   /*************************************************************************/
    737   /*                                                                       */
    738   /* <Function>                                                            */
    739   /*    FT_Get_CMap_Format                                                 */
    740   /*                                                                       */
    741   /* <Description>                                                         */
    742   /*    Return TrueType/sfnt specific cmap format.                         */
    743   /*                                                                       */
    744   /* <Input>                                                               */
    745   /*    charmap ::                                                         */
    746   /*      The target charmap.                                              */
    747   /*                                                                       */
    748   /* <Return>                                                              */
    749   /*    The format of `charmap'.  If `charmap' doesn't belong to a         */
    750   /*    TrueType/sfnt face, return -1.                                     */
    751   /*                                                                       */
    752   FT_EXPORT( FT_Long )
    753   FT_Get_CMap_Format( FT_CharMap  charmap );
    754 
    755   /* */
    756 
    757 
    758 FT_END_HEADER
    759 
    760 #endif /* __TTTABLES_H__ */
    761 
    762 
    763 /* END */
    764