/***************************************************************************//*                                                                         *//*  tttables.h                                                             *//*                                                                         *//*    Basic SFNT/TrueType tables definitions and interface                 *//*    (specification only).                                                *//*                                                                         *//*  Copyright 1996-2001 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_HFT_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               :: 10 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;