freetype2/include/freetype/tttables.h

764 lines
39 KiB
C

/***************************************************************************/
/* */
/* tttables.h */
/* */
/* Basic SFNT/TrueType tables definitions and interface */
/* (specification only). */
/* */
/* Copyright 1996-2005, 2008-2011 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
/* modified, and distributed under the terms of the FreeType project */
/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/***************************************************************************/
#ifndef __TTTABLES_H__
#define __TTTABLES_H__
#include <ft2build.h>
#include FT_FREETYPE_H
#ifdef FREETYPE_H
#error "freetype.h of FreeType 1 has been loaded!"
#error "Please fix the directory search order for header files"
#error "so that freetype.h of FreeType 2 is found first."
#endif
FT_BEGIN_HEADER
/*************************************************************************/
/* */
/* <Section> */
/* truetype_tables */
/* */
/* <Title> */
/* TrueType Tables */
/* */
/* <Abstract> */
/* TrueType specific table types and functions. */
/* */
/* <Description> */
/* This section contains the definition of TrueType-specific tables */
/* as well as some routines used to access and process them. */
/* */
/*************************************************************************/
/*************************************************************************/
/* */
/* <Struct> */
/* TT_Header */
/* */
/* <Description> */
/* A structure used to model a TrueType font header table. All */
/* fields follow the TrueType specification. */
/* */
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;
/*************************************************************************/
/* */
/* <Struct> */
/* TT_HoriHeader */
/* */
/* <Description> */
/* 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. */
/* */
/* <Fields> */
/* Version :: The table version. */
/* */
/* Ascender :: The font's ascender, i.e., the distance */
/* from the baseline to the top-most of all */
/* glyph points found in the font. */
/* */
/* This value is invalid in many fonts, as */
/* it is usually set by the font designer, */
/* and often reflects only a portion of the */
/* glyphs found in the font (maybe ASCII). */
/* */
/* You should use the `sTypoAscender' field */
/* of the OS/2 table instead if you want */
/* the correct one. */
/* */
/* Descender :: The font's descender, i.e., the distance */
/* from the baseline to the bottom-most of */
/* all glyph points found in the font. It */
/* is negative. */
/* */
/* This value is invalid in many fonts, as */
/* it is usually set by the font designer, */
/* and often reflects only a portion of the */
/* glyphs found in the font (maybe ASCII). */
/* */
/* You should use the `sTypoDescender' */
/* field of the OS/2 table instead if you */
/* want the correct one. */
/* */
/* Line_Gap :: The font's line gap, i.e., the distance */
/* to add to the ascender and descender to */
/* get the BTB, i.e., the */
/* baseline-to-baseline distance for the */
/* font. */
/* */
/* advance_Width_Max :: This field is the maximum of all advance */
/* widths found in the font. It can be */
/* used to compute the maximum width of an */
/* arbitrary string of text. */
/* */
/* min_Left_Side_Bearing :: The minimum left side bearing of all */
/* glyphs within the font. */
/* */
/* min_Right_Side_Bearing :: The minimum right side bearing of all */
/* glyphs within the font. */
/* */
/* xMax_Extent :: The maximum horizontal extent (i.e., the */
/* `width' of a glyph's bounding box) for */
/* all glyphs in the font. */
/* */
/* caret_Slope_Rise :: The rise coefficient of the cursor's */
/* slope of the cursor (slope=rise/run). */
/* */
/* caret_Slope_Run :: The run coefficient of the cursor's */
/* slope. */
/* */
/* Reserved :: 8~reserved bytes. */
/* */
/* metric_Data_Format :: Always~0. */
/* */
/* number_Of_HMetrics :: Number of HMetrics entries in the `hmtx' */
/* table -- this value can be smaller than */
/* the total number of glyphs in the font. */
/* */
/* long_metrics :: A pointer into the `hmtx' table. */
/* */
/* short_metrics :: A pointer into the `hmtx' table. */
/* */
/* <Note> */
/* 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_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;
/*************************************************************************/
/* */
/* <Struct> */
/* TT_VertHeader */
/* */
/* <Description> */
/* 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. */
/* */
/* <Fields> */
/* Version :: The table version. */
/* */
/* Ascender :: The font's ascender, i.e., the distance */
/* from the baseline to the top-most of */
/* all glyph points found in the font. */
/* */
/* This value is invalid in many fonts, as */
/* it is usually set by the font designer, */
/* and often reflects only a portion of */
/* the glyphs found in the font (maybe */
/* ASCII). */
/* */
/* You should use the `sTypoAscender' */
/* field of the OS/2 table instead if you */
/* want the correct one. */
/* */
/* Descender :: The font's descender, i.e., the */
/* distance from the baseline to the */
/* bottom-most of all glyph points found */
/* in the font. It is negative. */
/* */
/* This value is invalid in many fonts, as */
/* it is usually set by the font designer, */
/* and often reflects only a portion of */
/* the glyphs found in the font (maybe */
/* ASCII). */
/* */
/* You should use the `sTypoDescender' */
/* field of the OS/2 table instead if you */
/* want the correct one. */
/* */
/* Line_Gap :: The font's line gap, i.e., the distance */
/* to add to the ascender and descender to */
/* get the BTB, i.e., the */
/* baseline-to-baseline distance for the */
/* font. */
/* */
/* advance_Height_Max :: This field is the maximum of all */
/* advance heights found in the font. It */
/* can be used to compute the maximum */
/* height of an arbitrary string of text. */
/* */
/* min_Top_Side_Bearing :: The minimum top side bearing of all */
/* glyphs within the font. */
/* */
/* min_Bottom_Side_Bearing :: The minimum bottom side bearing of all */
/* glyphs within the font. */
/* */
/* yMax_Extent :: The maximum vertical extent (i.e., the */
/* `height' of a glyph's bounding box) for */
/* all glyphs in the font. */
/* */
/* caret_Slope_Rise :: The rise coefficient of the cursor's */
/* slope of the cursor (slope=rise/run). */
/* */
/* caret_Slope_Run :: The run coefficient of the cursor's */
/* slope. */
/* */
/* caret_Offset :: The cursor's offset for slanted fonts. */
/* This value is `reserved' in vmtx */
/* version 1.0. */
/* */
/* Reserved :: 8~reserved bytes. */
/* */
/* metric_Data_Format :: Always~0. */
/* */
/* number_Of_HMetrics :: Number of VMetrics entries in the */
/* `vmtx' table -- this value can be */
/* smaller than the total number of glyphs */
/* in the font. */
/* */
/* long_metrics :: A pointer into the `vmtx' table. */
/* */
/* short_metrics :: A pointer into the `vmtx' table. */
/* */
/* <Note> */
/* 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;
/*************************************************************************/
/* */
/* <Struct> */
/* TT_OS2 */
/* */
/* <Description> */
/* A structure used to model a TrueType OS/2 table. This is the long */
/* table version. All fields comply to the TrueType specification. */
/* */
/* Note that we now support old Mac fonts which do not include an */
/* OS/2 table. In this case, the `version' field is always set to */
/* 0xFFFF. */
/* */
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 tables: */
FT_ULong ulCodePageRange1; /* Bits 0-31 */
FT_ULong ulCodePageRange2; /* Bits 32-63 */
/* only version 2 tables: */
FT_Short sxHeight;
FT_Short sCapHeight;
FT_UShort usDefaultChar;
FT_UShort usBreakChar;
FT_UShort usMaxContext;
} TT_OS2;
/*************************************************************************/
/* */
/* <Struct> */
/* TT_Postscript */
/* */
/* <Description> */
/* 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_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;
/*************************************************************************/
/* */
/* <Struct> */
/* TT_PCLT */
/* */
/* <Description> */
/* A structure used to model a TrueType PCLT table. All fields */
/* comply to the TrueType specification. */
/* */
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;
/*************************************************************************/
/* */
/* <Struct> */
/* TT_MaxProfile */
/* */
/* <Description> */
/* 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. */
/* */
/* <Fields> */
/* version :: The version number. */
/* */
/* numGlyphs :: The number of glyphs in this TrueType */
/* font. */
/* */
/* maxPoints :: The maximum number of points in a */
/* non-composite TrueType glyph. See also */
/* the structure element */
/* `maxCompositePoints'. */
/* */
/* maxContours :: The maximum number of contours in a */
/* non-composite TrueType glyph. See also */
/* the structure element */
/* `maxCompositeContours'. */
/* */
/* maxCompositePoints :: The maximum number of points in a */
/* composite TrueType glyph. See also the */
/* structure element `maxPoints'. */
/* */
/* maxCompositeContours :: The maximum number of contours in a */
/* composite TrueType glyph. See also the */
/* structure element `maxContours'. */
/* */
/* maxZones :: The maximum number of zones used for */
/* glyph hinting. */
/* */
/* maxTwilightPoints :: The maximum number of points in the */
/* twilight zone used for glyph hinting. */
/* */
/* maxStorage :: The maximum number of elements in the */
/* storage area used for glyph hinting. */
/* */
/* maxFunctionDefs :: The maximum number of function */
/* definitions in the TrueType bytecode for */
/* this font. */
/* */
/* maxInstructionDefs :: The maximum number of instruction */
/* definitions in the TrueType bytecode for */
/* this font. */
/* */
/* maxStackElements :: The maximum number of stack elements used */
/* during bytecode interpretation. */
/* */
/* maxSizeOfInstructions :: The maximum number of TrueType opcodes */
/* used for glyph hinting. */
/* */
/* maxComponentElements :: The maximum number of simple (i.e., non- */
/* composite) glyphs in a composite glyph. */
/* */
/* maxComponentDepth :: The maximum nesting depth of composite */
/* glyphs. */
/* */
/* <Note> */
/* This structure is only used during font loading. */
/* */
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;
/*************************************************************************/
/* */
/* <Enum> */
/* FT_Sfnt_Tag */
/* */
/* <Description> */
/* An enumeration used to specify the index of an SFNT table. */
/* Used in the @FT_Get_Sfnt_Table API function. */
/* */
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;
/* */
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_Sfnt_Table */
/* */
/* <Description> */
/* Return a pointer to a given SFNT table within a face. */
/* */
/* <Input> */
/* face :: A handle to the source. */
/* */
/* tag :: The index of the SFNT table. */
/* */
/* <Return> */
/* 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. */
/* */
/* <Note> */
/* 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. */
/* */
FT_EXPORT( void* )
FT_Get_Sfnt_Table( FT_Face face,
FT_Sfnt_Tag tag );
/**************************************************************************
*
* @function:
* FT_Load_Sfnt_Table
*
* @description:
* Load any font table into client memory.
*
* @input:
* face ::
* A handle to the source face.
*
* tag ::
* The four-byte tag of the table to load. Use the value~0 if you want
* to access the whole font file. Otherwise, you can use one of the
* definitions found in the @FT_TRUETYPE_TAGS_H file, or forge a new
* one with @FT_MAKE_TAG.
*
* offset ::
* The starting offset in the table (or file if tag == 0).
*
* @output:
* buffer ::
* The target buffer address. The client must ensure that the memory
* array is big enough to hold the data.
*
* @inout:
* length ::
* If the `length' parameter is NULL, then try to load the whole table.
* Return an error code if it fails.
*
* Else, if `*length' is~0, exit immediately while returning the
* table's (or file) full size in it.
*
* Else the number of bytes to read from the table or file, from the
* starting offset.
*
* @return:
* FreeType error code. 0~means success.
*
* @note:
* 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 ... }
* }
*/
FT_EXPORT( FT_Error )
FT_Load_Sfnt_Table( FT_Face face,
FT_ULong tag,
FT_Long offset,
FT_Byte* buffer,
FT_ULong* length );
/**************************************************************************
*
* @function:
* FT_Sfnt_Table_Info
*
* @description:
* Return information on an SFNT table.
*
* @input:
* face ::
* A handle to the source face.
*
* table_index ::
* The index of an SFNT table. The function returns
* FT_Err_Table_Missing for an invalid value.
*
* @inout:
* tag ::
* The name tag of the SFNT table. If the value is NULL, `table_index'
* is ignored, and `length' returns the number of SFNT tables in the
* font.
*
* @output:
* length ::
* The length of the SFNT table (or the number of SFNT tables, depending
* on `tag').
*
* @return:
* FreeType error code. 0~means success.
*
* @note:
* SFNT tables with length zero are treated as missing.
*
*/
FT_EXPORT( FT_Error )
FT_Sfnt_Table_Info( FT_Face face,
FT_UInt table_index,
FT_ULong *tag,
FT_ULong *length );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_CMap_Language_ID */
/* */
/* <Description> */
/* Return TrueType/sfnt specific cmap language ID. Definitions of */
/* language ID values are in `freetype/ttnameid.h'. */
/* */
/* <Input> */
/* charmap :: */
/* The target charmap. */
/* */
/* <Return> */
/* The language ID of `charmap'. If `charmap' doesn't belong to a */
/* TrueType/sfnt face, just return~0 as the default value. */
/* */
FT_EXPORT( FT_ULong )
FT_Get_CMap_Language_ID( FT_CharMap charmap );
/*************************************************************************/
/* */
/* <Function> */
/* FT_Get_CMap_Format */
/* */
/* <Description> */
/* Return TrueType/sfnt specific cmap format. */
/* */
/* <Input> */
/* charmap :: */
/* The target charmap. */
/* */
/* <Return> */
/* The format of `charmap'. If `charmap' doesn't belong to a */
/* TrueType/sfnt face, return -1. */
/* */
FT_EXPORT( FT_Long )
FT_Get_CMap_Format( FT_CharMap charmap );
/* */
FT_END_HEADER
#endif /* __TTTABLES_H__ */
/* END */