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Diffstat (limited to 'modules/freetype2/include/freetype/tttables.h')
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diff --git a/modules/freetype2/include/freetype/tttables.h b/modules/freetype2/include/freetype/tttables.h new file mode 100644 index 0000000000..a9f60e7620 --- /dev/null +++ b/modules/freetype2/include/freetype/tttables.h @@ -0,0 +1,855 @@ +/**************************************************************************** + * + * tttables.h + * + * Basic SFNT/TrueType tables definitions and interface + * (specification only). + * + * Copyright (C) 1996-2023 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 <freetype/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 definitions of some basic tables specific to + * TrueType and OpenType as well as some routines used to access and + * process them. + * + * @order: + * TT_Header + * TT_HoriHeader + * TT_VertHeader + * TT_OS2 + * TT_Postscript + * TT_PCLT + * TT_MaxProfile + * + * FT_Sfnt_Tag + * FT_Get_Sfnt_Table + * FT_Load_Sfnt_Table + * FT_Sfnt_Table_Info + * + * FT_Get_CMap_Language_ID + * FT_Get_CMap_Format + * + * FT_PARAM_TAG_UNPATENTED_HINTING + * + */ + + + /************************************************************************** + * + * @struct: + * TT_Header + * + * @description: + * A structure to model a TrueType font header table. All fields follow + * the OpenType specification. The 64-bit timestamps are stored in + * two-element arrays `Created` and `Modified`, first the upper then + * the lower 32~bits. + */ + 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_ULong Created [2]; + FT_ULong 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 to model a TrueType horizontal header, the 'hhea' table, + * as well as the corresponding horizontal metrics table, 'hmtx'. + * + * @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. + * + * caret_Offset :: + * The cursor's offset for slanted fonts. + * + * 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: + * For an OpenType variation font, the values of the following fields can + * change after a call to @FT_Set_Var_Design_Coordinates (and friends) if + * the font contains an 'MVAR' table: `caret_Slope_Rise`, + * `caret_Slope_Run`, and `caret_Offset`. + */ + 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 OpenType 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, 'vmtx'. + * + * @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. + * + * Reserved :: + * 8~reserved bytes. + * + * metric_Data_Format :: + * Always~0. + * + * number_Of_VMetrics :: + * 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: + * For an OpenType variation font, the values of the following fields can + * change after a call to @FT_Set_Var_Design_Coordinates (and friends) if + * the font contains an 'MVAR' table: `Ascender`, `Descender`, + * `Line_Gap`, `caret_Slope_Rise`, `caret_Slope_Run`, and `caret_Offset`. + */ + 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 top-sb */ + FT_Short min_Bottom_Side_Bearing; /* minimum bottom-sb */ + FT_Short yMax_Extent; /* 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 OpenType specification */ + /* but they are used to connect the metrics header to the relevant */ + /* 'vmtx' table. */ + + void* long_metrics; + void* short_metrics; + + } TT_VertHeader; + + + /************************************************************************** + * + * @struct: + * TT_OS2 + * + * @description: + * A structure 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. + * + * @note: + * For an OpenType variation font, the values of the following fields can + * change after a call to @FT_Set_Var_Design_Coordinates (and friends) if + * the font contains an 'MVAR' table: `sCapHeight`, `sTypoAscender`, + * `sTypoDescender`, `sTypoLineGap`, `sxHeight`, `usWinAscent`, + * `usWinDescent`, `yStrikeoutPosition`, `yStrikeoutSize`, + * `ySubscriptXOffset`, `ySubScriptXSize`, `ySubscriptYOffset`, + * `ySubscriptYSize`, `ySuperscriptXOffset`, `ySuperscriptXSize`, + * `ySuperscriptYOffset`, and `ySuperscriptYSize`. + * + * Possible values for bits in the `ulUnicodeRangeX` fields are given by + * the @TT_UCR_XXX macros. + */ + + typedef struct TT_OS2_ + { + FT_UShort version; /* 0x0001 - more or 0xFFFF */ + FT_Short xAvgCharWidth; + FT_UShort usWeightClass; + FT_UShort usWidthClass; + FT_UShort 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 (1/20 points) */ + FT_UShort usUpperOpticalPointSize; /* in twips (1/20 points) */ + + } TT_OS2; + + + /************************************************************************** + * + * @struct: + * TT_Postscript + * + * @description: + * A structure to model a TrueType 'post' table. All fields comply to + * the OpenType specification. This structure does not reference a + * font's PostScript glyph names; use @FT_Get_Glyph_Name to retrieve + * them. + * + * @note: + * For an OpenType variation font, the values of the following fields can + * change after a call to @FT_Set_Var_Design_Coordinates (and friends) if + * the font contains an 'MVAR' table: `underlinePosition` and + * `underlineThickness`. + */ + 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 'post' table, but we don't */ + /* load them by default. */ + + } TT_Postscript; + + + /************************************************************************** + * + * @struct: + * TT_PCLT + * + * @description: + * A structure to model a TrueType 'PCLT' table. All fields comply to + * the OpenType 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 ('maxp') table contains many max values, which can + * be used to pre-allocate arrays for speeding up glyph loading and + * hinting. + * + * @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 `maxCompositePoints`. + * + * maxContours :: + * The maximum number of contours in a non-composite TrueType glyph. + * See also `maxCompositeContours`. + * + * maxCompositePoints :: + * The maximum number of points in a composite TrueType glyph. See + * also `maxPoints`. + * + * maxCompositeContours :: + * The maximum number of contours in a composite TrueType glyph. See + * also `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 to specify indices of SFNT tables loaded and parsed by + * FreeType during initialization of an SFNT font. Used in the + * @FT_Get_Sfnt_Table API function. + * + * @values: + * FT_SFNT_HEAD :: + * To access the font's @TT_Header structure. + * + * FT_SFNT_MAXP :: + * To access the font's @TT_MaxProfile structure. + * + * FT_SFNT_OS2 :: + * To access the font's @TT_OS2 structure. + * + * FT_SFNT_HHEA :: + * To access the font's @TT_HoriHeader structure. + * + * FT_SFNT_VHEA :: + * To access the font's @TT_VertHeader structure. + * + * FT_SFNT_POST :: + * To access the font's @TT_Postscript structure. + * + * FT_SFNT_PCLT :: + * To access the font's @TT_PCLT structure. + */ + typedef enum FT_Sfnt_Tag_ + { + FT_SFNT_HEAD, + FT_SFNT_MAXP, + FT_SFNT_OS2, + FT_SFNT_HHEA, + FT_SFNT_VHEA, + FT_SFNT_POST, + FT_SFNT_PCLT, + + FT_SFNT_MAX + + } FT_Sfnt_Tag; + + /* these constants are deprecated; use the corresponding `FT_Sfnt_Tag` */ + /* values instead */ +#define ft_sfnt_head FT_SFNT_HEAD +#define ft_sfnt_maxp FT_SFNT_MAXP +#define ft_sfnt_os2 FT_SFNT_OS2 +#define ft_sfnt_hhea FT_SFNT_HHEA +#define ft_sfnt_vhea FT_SFNT_VHEA +#define ft_sfnt_post FT_SFNT_POST +#define ft_sfnt_pclt FT_SFNT_PCLT + + + /************************************************************************** + * + * @function: + * FT_Get_Sfnt_Table + * + * @description: + * Return a pointer to a given SFNT table stored 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 `NULL` 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. + * + * @example: + * Here is an example demonstrating access to the 'vhea' table. + * + * ``` + * TT_VertHeader* vert_header; + * + * + * vert_header = + * (TT_VertHeader*)FT_Get_Sfnt_Table( face, FT_SFNT_VHEA ); + * ``` + */ + FT_EXPORT( void* ) + FT_Get_Sfnt_Table( FT_Face face, + FT_Sfnt_Tag tag ); + + + /************************************************************************** + * + * @function: + * FT_Load_Sfnt_Table + * + * @description: + * Load any SFNT font table into client memory. + * + * @input: + * face :: + * A handle to the source face. + * + * tag :: + * The four-byte tag of the table to load. Use 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`, 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 ... } + * ``` + * + * 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_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: + * While parsing fonts, FreeType handles SFNT tables with length zero 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 cmap language ID as specified in the OpenType standard. + * Definitions of language ID values are in file @FT_TRUETYPE_IDS_H. + * + * @input: + * charmap :: + * The target charmap. + * + * @return: + * The language ID of `charmap`. If `charmap` doesn't belong to an 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_ULong ) + FT_Get_CMap_Language_ID( FT_CharMap charmap ); + + + /************************************************************************** + * + * @function: + * FT_Get_CMap_Format + * + * @description: + * Return the format of an SFNT 'cmap' table. + * + * @input: + * charmap :: + * The target charmap. + * + * @return: + * The format of `charmap`. If `charmap` doesn't belong to an SFNT face, + * return -1. + */ + FT_EXPORT( FT_Long ) + FT_Get_CMap_Format( FT_CharMap charmap ); + + /* */ + + +FT_END_HEADER + +#endif /* TTTABLES_H_ */ + + +/* END */ |