tttypes.h

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

   *                                         the corresponding double quotes.
   *                         For atoms    => Offset into string table.
   *                         For integers => Direct value.
   *
   * All strings in the string table consist of bytes and are
   * zero-terminated.
   *
   */

#ifdef TT_CONFIG_OPTION_BDF

  typedef struct  TT_BDFRec_
  {
    FT_Byte*   table;
    FT_Byte*   table_end;
    FT_Byte*   strings;
    FT_UInt32  strings_size;
    FT_UInt    num_strikes;
    FT_Bool    loaded;

  } TT_BDFRec, *TT_BDF;

#endif /* TT_CONFIG_OPTION_BDF */

  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/
  /***                                                                   ***/
  /***                                                                   ***/
  /***                  ORIGINAL TT_FACE CLASS DEFINITION                ***/
  /***                                                                   ***/
  /***                                                                   ***/
  /*************************************************************************/
  /*************************************************************************/
  /*************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* This structure/class is defined here because it is common to the      */
  /* following formats: TTF, OpenType-TT, and OpenType-CFF.                */
  /*                                                                       */
  /* Note, however, that the classes TT_Size and TT_GlyphSlot are not      */
  /* shared between font drivers, and are thus defined in `ttobjs.h'.      */
  /*                                                                       */
  /*************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    TT_Face                                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a TrueType face/font object.  A TT_Face encapsulates   */
  /*    the resolution and scaling independent parts of a TrueType font    */
  /*    resource.                                                          */
  /*                                                                       */
  /* <Note>                                                                */
  /*    The TT_Face structure is also used as a `parent class' for the     */
  /*    OpenType-CFF class (T2_Face).                                      */
  /*                                                                       */
  typedef struct TT_FaceRec_*  TT_Face;


  /* a function type used for the truetype bytecode interpreter hooks */
  typedef FT_Error
  (*TT_Interpreter)( void*  exec_context );

  /* forward declaration */
  typedef struct TT_LoaderRec_*  TT_Loader;


  /*************************************************************************/
  /*                                                                       */
  /* <FuncType>                                                            */
  /*    TT_Loader_GotoTableFunc                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Seeks a stream to the start of a given TrueType table.             */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face   :: A handle to the target face object.                      */
  /*                                                                       */
  /*    tag    :: A 4-byte tag used to name the table.                     */
  /*                                                                       */
  /*    stream :: The input stream.                                        */
  /*                                                                       */
  /* <Output>                                                              */
  /*    length :: The length of the table in bytes.  Set to 0 if not       */
  /*              needed.                                                  */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    The stream cursor must be at the font file's origin.               */
  /*                                                                       */
  typedef FT_Error
  (*TT_Loader_GotoTableFunc)( TT_Face    face,
                              FT_ULong   tag,
                              FT_Stream  stream,
                              FT_ULong*  length );


  /*************************************************************************/
  /*                                                                       */
  /* <FuncType>                                                            */
  /*    TT_Loader_StartGlyphFunc                                           */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Seeks a stream to the start of a given glyph element, and opens a  */
  /*    frame for it.                                                      */
  /*                                                                       */
  /* <Input>                                                               */
  /*    loader      :: The current TrueType glyph loader object.           */
  /*                                                                       */
  /*    glyph index :: The index of the glyph to access.                   */
  /*                                                                       */
  /*    offset      :: The offset of the glyph according to the            */
  /*                   `locations' table.                                  */
  /*                                                                       */
  /*    byte_count  :: The size of the frame in bytes.                     */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    This function is normally equivalent to FT_STREAM_SEEK(offset)     */
  /*    followed by FT_FRAME_ENTER(byte_count) with the loader's stream,   */
  /*    but alternative formats (e.g. compressed ones) might use something */
  /*    different.                                                         */
  /*                                                                       */
  typedef FT_Error
  (*TT_Loader_StartGlyphFunc)( TT_Loader  loader,
                               FT_UInt    glyph_index,
                               FT_ULong   offset,
                               FT_UInt    byte_count );


  /*************************************************************************/
  /*                                                                       */
  /* <FuncType>                                                            */
  /*    TT_Loader_ReadGlyphFunc                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Reads one glyph element (its header, a simple glyph, or a          */
  /*    composite) from the loader's current stream frame.                 */
  /*                                                                       */
  /* <Input>                                                               */
  /*    loader :: The current TrueType glyph loader object.                */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  typedef FT_Error
  (*TT_Loader_ReadGlyphFunc)( TT_Loader  loader );


  /*************************************************************************/
  /*                                                                       */
  /* <FuncType>                                                            */
  /*    TT_Loader_EndGlyphFunc                                             */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Closes the current loader stream frame for the glyph.              */
  /*                                                                       */
  /* <Input>                                                               */
  /*    loader :: The current TrueType glyph loader object.                */
  /*                                                                       */
  typedef void
  (*TT_Loader_EndGlyphFunc)( TT_Loader  loader );


  /*************************************************************************/
  /*                                                                       */
  /*                         TrueType Face Type                            */
  /*                                                                       */
  /* <Struct>                                                              */
  /*    TT_Face                                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    The TrueType face class.  These objects model the resolution and   */
  /*    point-size independent data found in a TrueType font file.         */
  /*                                                                       */
  /* <Fields>                                                              */
  /*    root                 :: The base FT_Face structure, managed by the */
  /*                            base layer.                                */
  /*                                                                       */
  /*    ttc_header           :: The TrueType collection header, used when  */
  /*                            the file is a `ttc' rather than a `ttf'.   */
  /*                            For ordinary font files, the field         */
  /*                            `ttc_header.count' is set to 0.            */
  /*                                                                       */
  /*    format_tag           :: The font format tag.                       */
  /*                                                                       */
  /*    num_tables           :: The number of TrueType tables in this font */
  /*                            file.                                      */
  /*                                                                       */
  /*    dir_tables           :: The directory of TrueType tables for this  */
  /*                            font file.                                 */
  /*                                                                       */
  /*    header               :: The font's font header (`head' table).     */
  /*                            Read on font opening.                      */
  /*                                                                       */
  /*    horizontal           :: The font's horizontal header (`hhea'       */
  /*                            table).  This field also contains the      */
  /*                            associated horizontal metrics table        */
  /*                            (`hmtx').                                  */
  /*                                                                       */
  /*    max_profile          :: The font's maximum profile table.  Read on */
  /*                            font opening.  Note that some maximum      */
  /*                            values cannot be taken directly from this  */
  /*                            table.  We thus define additional fields   */
  /*                            below to hold the computed maxima.         */
  /*                                                                       */
  /*    vertical_info        :: A boolean which is set when the font file  */
  /*                            contains vertical metrics.  If not, the    */
  /*                            value of the `vertical' field is           */
  /*                            undefined.