tttables.h

奇趣公司比较新的qt/emd版本

/***************************************************************************/
/*                                                                         */
/*  tttables.h                                                             */
/*                                                                         */
/*    Basic SFNT/TrueType tables definitions and interface                 */
/*    (specification only).                                                */
/*                                                                         */
/*  Copyright 1996-2001, 2002, 2003, 2004, 2005 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               :: 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;


  /*************************************************************************/
  /*                                                                       */
  /* <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     */