#define TT_PLATFORM_APPLE_UNICODE  0
#define TT_PLATFORM_MACINTOSH      1
#define TT_PLATFORM_ISO            2 /* deprecated */
#define TT_PLATFORM_MICROSOFT      3
#define TT_PLATFORM_CUSTOM         4
#define TT_PLATFORM_ADOBE          7 /* artificial */

A list of valid values for the ‘platform_id’ identifier code in FT_CharMapRec and FT_SfntName structures.

#define TT_APPLE_ID_DEFAULT           0 /* Unicode 1.0 */
#define TT_APPLE_ID_UNICODE_1_1       1 /* specify Hangul at U+34xx */
#define TT_APPLE_ID_ISO_10646         2 /* deprecated */
#define TT_APPLE_ID_UNICODE_2_0       3 /* or later */
#define TT_APPLE_ID_UNICODE_32        4 /* 2.0 or later, full repertoire */
#define TT_APPLE_ID_VARIANT_SELECTOR  5 /* variation selector data */

A list of valid values for the ‘encoding_id’ for TT_PLATFORM_APPLE_UNICODE charmaps and name entries.

#define TT_MAC_ID_ROMAN                 0
#define TT_MAC_ID_JAPANESE              1
#define TT_MAC_ID_TRADITIONAL_CHINESE   2
#define TT_MAC_ID_KOREAN                3
#define TT_MAC_ID_ARABIC                4
#define TT_MAC_ID_HEBREW                5
#define TT_MAC_ID_GREEK                 6
#define TT_MAC_ID_RUSSIAN               7
#define TT_MAC_ID_RSYMBOL               8
#define TT_MAC_ID_DEVANAGARI            9
#define TT_MAC_ID_GURMUKHI             10
#define TT_MAC_ID_GUJARATI             11
#define TT_MAC_ID_ORIYA                12
#define TT_MAC_ID_BENGALI              13
#define TT_MAC_ID_TAMIL                14
#define TT_MAC_ID_TELUGU               15
#define TT_MAC_ID_KANNADA              16
#define TT_MAC_ID_MALAYALAM            17
#define TT_MAC_ID_SINHALESE            18
#define TT_MAC_ID_BURMESE              19
#define TT_MAC_ID_KHMER                20
#define TT_MAC_ID_THAI                 21
#define TT_MAC_ID_LAOTIAN              22
#define TT_MAC_ID_GEORGIAN             23
#define TT_MAC_ID_ARMENIAN             24
#define TT_MAC_ID_MALDIVIAN            25
#define TT_MAC_ID_SIMPLIFIED_CHINESE   25
#define TT_MAC_ID_TIBETAN              26
#define TT_MAC_ID_MONGOLIAN            27
#define TT_MAC_ID_GEEZ                 28
#define TT_MAC_ID_SLAVIC               29
#define TT_MAC_ID_VIETNAMESE           30
#define TT_MAC_ID_SINDHI               31
#define TT_MAC_ID_UNINTERP             32

A list of valid values for the ‘encoding_id’ for TT_PLATFORM_MACINTOSH charmaps and name entries.

#define TT_ISO_ID_7BIT_ASCII  0
#define TT_ISO_ID_10646       1
#define TT_ISO_ID_8859_1      2

A list of valid values for the ‘encoding_id’ for TT_PLATFORM_ISO charmaps and name entries.

Their use is now deprecated.

#define TT_MS_ID_SYMBOL_CS    0
#define TT_MS_ID_UNICODE_CS   1
#define TT_MS_ID_SJIS         2
#define TT_MS_ID_GB2312       3
#define TT_MS_ID_BIG_5        4
#define TT_MS_ID_WANSUNG      5
#define TT_MS_ID_JOHAB        6
#define TT_MS_ID_UCS_4       10

A list of valid values for the ‘encoding_id’ for TT_PLATFORM_MICROSOFT charmaps and name entries.

#define TT_ADOBE_ID_STANDARD  0
#define TT_ADOBE_ID_EXPERT    1
#define TT_ADOBE_ID_CUSTOM    2
#define TT_ADOBE_ID_LATIN_1   3

A list of valid values for the ‘encoding_id’ for TT_PLATFORM_ADOBE charmaps. This is a FreeType-specific extension!

  typedef struct  TT_Header_
  {
    FT_Fixed   Table_Version;
    FT_Fixed   Font_Revision;

    FT_Long    CheckSum_Adjust;
    FT_Long    Magic_Number;

    FT_UShort  Flags;
    FT_UShort  Units_Per_EM;

    FT_Long    Created [2];
    FT_Long    Modified[2];

    FT_Short   xMin;
    FT_Short   yMin;
    FT_Short   xMax;
    FT_Short   yMax;

    FT_UShort  Mac_Style;
    FT_UShort  Lowest_Rec_PPEM;

    FT_Short   Font_Direction;
    FT_Short   Index_To_Loc_Format;
    FT_Short   Glyph_Data_Format;

  } TT_Header;

A structure used to model a TrueType font header table. All fields follow the TrueType specification.

  typedef struct  TT_HoriHeader_
  {
    FT_Fixed   Version;
    FT_Short   Ascender;
    FT_Short   Descender;
    FT_Short   Line_Gap;

    FT_UShort  advance_Width_Max;      /* advance width maximum */

    FT_Short   min_Left_Side_Bearing;  /* minimum left-sb       */
    FT_Short   min_Right_Side_Bearing; /* minimum right-sb      */
    FT_Short   xMax_Extent;            /* xmax extents          */
    FT_Short   caret_Slope_Rise;
    FT_Short   caret_Slope_Run;
    FT_Short   caret_Offset;

    FT_Short   Reserved[4];

    FT_Short   metric_Data_Format;
    FT_UShort  number_Of_HMetrics;

    /* The following fields are not defined by the TrueType specification */
    /* but they are used to connect the metrics header to the relevant    */
    /* `HMTX' table.                                                      */

    void*      long_metrics;
    void*      short_metrics;

  } TT_HoriHeader;

A structure used to model a TrueType horizontal header, the ‘hhea’ table, as well as the corresponding horizontal metrics table, i.e., the ‘hmtx’ table.

IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should be identical except for the names of their fields, which are different.

This ensures that a single function in the ‘ttload’ module is able to read both the horizontal and vertical headers.

  typedef struct  TT_VertHeader_
  {
    FT_Fixed   Version;
    FT_Short   Ascender;
    FT_Short   Descender;
    FT_Short   Line_Gap;

    FT_UShort  advance_Height_Max;      /* advance height maximum */

    FT_Short   min_Top_Side_Bearing;    /* minimum left-sb or top-sb       */
    FT_Short   min_Bottom_Side_Bearing; /* minimum right-sb or bottom-sb   */
    FT_Short   yMax_Extent;             /* xmax or ymax extents            */
    FT_Short   caret_Slope_Rise;
    FT_Short   caret_Slope_Run;
    FT_Short   caret_Offset;

    FT_Short   Reserved[4];

    FT_Short   metric_Data_Format;
    FT_UShort  number_Of_VMetrics;

    /* The following fields are not defined by the TrueType specification */
    /* but they're used to connect the metrics header to the relevant     */
    /* `HMTX' or `VMTX' table.                                            */

    void*      long_metrics;
    void*      short_metrics;

  } TT_VertHeader;

A structure used to model a TrueType vertical header, the ‘vhea’ table, as well as the corresponding vertical metrics table, i.e., the ‘vmtx’ table.

IMPORTANT: The TT_HoriHeader and TT_VertHeader structures should be identical except for the names of their fields, which are different.

This ensures that a single function in the ‘ttload’ module is able to read both the horizontal and vertical headers.

  typedef struct  TT_OS2_
  {
    FT_UShort  version;                /* 0x0001 - more or 0xFFFF */
    FT_Short   xAvgCharWidth;
    FT_UShort  usWeightClass;
    FT_UShort  usWidthClass;
    FT_Short   fsType;
    FT_Short   ySubscriptXSize;
    FT_Short   ySubscriptYSize;
    FT_Short   ySubscriptXOffset;
    FT_Short   ySubscriptYOffset;
    FT_Short   ySuperscriptXSize;
    FT_Short   ySuperscriptYSize;
    FT_Short   ySuperscriptXOffset;
    FT_Short   ySuperscriptYOffset;
    FT_Short   yStrikeoutSize;
    FT_Short   yStrikeoutPosition;
    FT_Short   sFamilyClass;

    FT_Byte    panose[10];

    FT_ULong   ulUnicodeRange1;        /* Bits 0-31   */
    FT_ULong   ulUnicodeRange2;        /* Bits 32-63  */
    FT_ULong   ulUnicodeRange3;        /* Bits 64-95  */
    FT_ULong   ulUnicodeRange4;        /* Bits 96-127 */

    FT_Char    achVendID[4];

    FT_UShort  fsSelection;
    FT_UShort  usFirstCharIndex;
    FT_UShort  usLastCharIndex;
    FT_Short   sTypoAscender;
    FT_Short   sTypoDescender;
    FT_Short   sTypoLineGap;
    FT_UShort  usWinAscent;
    FT_UShort  usWinDescent;

    /* only version 1 and higher: */

    FT_ULong   ulCodePageRange1;       /* Bits 0-31   */
    FT_ULong   ulCodePageRange2;       /* Bits 32-63  */

    /* only version 2 and higher: */

    FT_Short   sxHeight;
    FT_Short   sCapHeight;
    FT_UShort  usDefaultChar;
    FT_UShort  usBreakChar;
    FT_UShort  usMaxContext;

    /* only version 5 and higher: */

    FT_UShort  usLowerOpticalPointSize;       /* in twips (1/20th points) */
    FT_UShort  usUpperOpticalPointSize;       /* in twips (1/20th points) */

  } TT_OS2;

A structure used to model a TrueType OS/2 table. All fields comply to the OpenType specification.

Note that we now support old Mac fonts that do not include an OS/2 table. In this case, the ‘version’ field is always set to 0xFFFF.

  typedef struct  TT_Postscript_
  {
    FT_Fixed  FormatType;
    FT_Fixed  italicAngle;
    FT_Short  underlinePosition;
    FT_Short  underlineThickness;
    FT_ULong  isFixedPitch;
    FT_ULong  minMemType42;
    FT_ULong  maxMemType42;
    FT_ULong  minMemType1;
    FT_ULong  maxMemType1;

    /* Glyph names follow in the file, but we don't   */
    /* load them by default.  See the ttpost.c file.  */

  } TT_Postscript;

A structure used to model a TrueType PostScript table. All fields comply to the TrueType specification. This structure does not reference the PostScript glyph names, which can be nevertheless accessed with the ‘ttpost’ module.

  typedef struct  TT_PCLT_
  {
    FT_Fixed   Version;
    FT_ULong   FontNumber;
    FT_UShort  Pitch;
    FT_UShort  xHeight;
    FT_UShort  Style;
    FT_UShort  TypeFamily;
    FT_UShort  CapHeight;
    FT_UShort  SymbolSet;
    FT_Char    TypeFace[16];
    FT_Char    CharacterComplement[8];
    FT_Char    FileName[6];
    FT_Char    StrokeWeight;
    FT_Char    WidthType;
    FT_Byte    SerifStyle;
    FT_Byte    Reserved;

  } TT_PCLT;

A structure used to model a TrueType PCLT table. All fields comply to the TrueType specification.

  typedef struct  TT_MaxProfile_
  {
    FT_Fixed   version;
    FT_UShort  numGlyphs;
    FT_UShort  maxPoints;
    FT_UShort  maxContours;
    FT_UShort  maxCompositePoints;
    FT_UShort  maxCompositeContours;
    FT_UShort  maxZones;
    FT_UShort  maxTwilightPoints;
    FT_UShort  maxStorage;
    FT_UShort  maxFunctionDefs;
    FT_UShort  maxInstructionDefs;
    FT_UShort  maxStackElements;
    FT_UShort  maxSizeOfInstructions;
    FT_UShort  maxComponentElements;
    FT_UShort  maxComponentDepth;

  } TT_MaxProfile;

The maximum profile is a table containing many max values, which can be used to pre-allocate arrays. This ensures that no memory allocation occurs during a glyph load.

This structure is only used during font loading.

  typedef enum  FT_Sfnt_Tag_
  {
    ft_sfnt_head = 0,    /* TT_Header     */
    ft_sfnt_maxp = 1,    /* TT_MaxProfile */
    ft_sfnt_os2  = 2,    /* TT_OS2        */
    ft_sfnt_hhea = 3,    /* TT_HoriHeader */
    ft_sfnt_vhea = 4,    /* TT_VertHeader */
    ft_sfnt_post = 5,    /* TT_Postscript */
    ft_sfnt_pclt = 6,    /* TT_PCLT       */

    sfnt_max   /* internal end mark */

  } FT_Sfnt_Tag;

An enumeration used to specify the index of an SFNT table. Used in the FT_Get_Sfnt_Table API function.

  FT_EXPORT( void* )
  FT_Get_Sfnt_Table( FT_Face      face,
                     FT_Sfnt_Tag  tag );

Return a pointer to a given SFNT table within a face.

A type-less pointer to the table. This will be 0 in case of error, or if the corresponding table was not found OR loaded from the file.

Use a typecast according to ‘tag’ to access the structure elements.

The table is owned by the face object and disappears with it.

This function is only useful to access SFNT tables that are loaded by the sfnt, truetype, and opentype drivers. See FT_Sfnt_Tag for a list.

Here an example how to access the ‘vhea’ table:

  TT_VertHeader*  vert_header;                                     
                                                                   
                                                                   
  vert_header =                                                    
    (TT_VertHeader*)FT_Get_Sfnt_Table( face, ft_sfnt_vhea );       

  FT_EXPORT( FT_Error )
  FT_Load_Sfnt_Table( FT_Face    face,
                      FT_ULong   tag,
                      FT_Long    offset,
                      FT_Byte*   buffer,
                      FT_ULong*  length );

Load any font table into client memory.

FreeType error code. 0 means success.

If you need to determine the table's length you should first call this function with ‘*length’ set to 0, as in the following example:

  FT_ULong  length = 0;


  error = FT_Load_Sfnt_Table( face, tag, 0, NULL, &length );
  if ( error ) { ... table does not exist ... }

  buffer = malloc( length );
  if ( buffer == NULL ) { ... not enough memory ... }

  error = FT_Load_Sfnt_Table( face, tag, 0, buffer, &length );
  if ( error ) { ... could not load table ... }

Note that structures like TT_Header or TT_OS2 can't be used with this function; they are limited to FT_Get_Sfnt_Table. Reason is that those structures depend on the processor architecture, with varying size (e.g. 32bit vs. 64bit) or order (big endian vs. little endian).

  FT_EXPORT( FT_Error )
  FT_Sfnt_Table_Info( FT_Face    face,
                      FT_UInt    table_index,
                      FT_ULong  *tag,
                      FT_ULong  *length );

Return information on an SFNT table.

FreeType error code. 0 means success.

While parsing fonts, FreeType handles SFNT tables with length zero as missing.

  FT_EXPORT( FT_ULong )
  FT_Get_CMap_Language_ID( FT_CharMap  charmap );

Return TrueType/sfnt specific cmap language ID. Definitions of language ID values are in ‘ttnameid.h’.

The language ID of ‘charmap’. If ‘charmap’ doesn't belong to a TrueType/sfnt face, just return 0 as the default value.

For a format 14 cmap (to access Unicode IVS), the return value is 0xFFFFFFFF.

  FT_EXPORT( FT_Long )
  FT_Get_CMap_Format( FT_CharMap  charmap );

Return TrueType/sfnt specific cmap format.

The format of ‘charmap’. If ‘charmap’ doesn't belong to a TrueType/sfnt face, return -1.

#define FT_PARAM_TAG_UNPATENTED_HINTING  FT_MAKE_TAG( 'u', 'n', 'p', 'a' )

A constant used as the tag of an FT_Parameter structure to indicate that unpatented methods only should be used by the TrueType bytecode interpreter for a typeface opened by FT_Open_Face.