ftxsbit.h

神龙卡开发原代码

  
  /*************************************************************/
  /*                                                           */
  /* <Struct> TT_SBit_Component                                */
  /*                                                           */
  /* <Description>                                             */
  /*    A simple structure to describe a compound sbit element */
  /*                                                           */
  /* <Fields>                                                  */
  /*    glyph_code :: element's glyph index                    */
  /*    x_offset   :: element's left bearing                   */
  /*    y_offset   :: element's top bearing                    */
  /*                                                           */
  typedef struct  TT_SBit_Component_
  {
    TT_UShort  glyph_code;
    TT_Char    x_offset;
    TT_Char    y_offset;

  } TT_SBit_Component;


  /*************************************************************/
  /*                                                           */
  /* <Struct> TT_SBit_Scale                                    */
  /*                                                           */
  /* <Description>                                             */
  /*    A structure used describe a given bitmap scaling       */
  /*    table, as defined for the `EBSC' table.                */
  /*                                                           */
  /* <Fields>                                                  */
  /*    hori   :: horizontal line metrics                      */
  /*    vert   :: vertical line metrics                        */
  /*                                                           */
  /*    x_ppem :: horizontal pixels per EM                     */
  /*    y_ppem :: vertical pixels per EM                       */
  /*                                                           */
  /*    x_ppem_substitute :: substitution x_ppem               */
  /*    y_ppem_substitute :: substitution y_ppem               */
  /*                                                           */
  typedef struct  TT_SBit_Scale_
  {
    TT_SBit_Line_Metrics  hori;
    TT_SBit_Line_Metrics  vert;

    TT_Byte               x_ppem;
    TT_Byte               y_ppem;

    TT_Byte               x_ppem_substitute;
    TT_Byte               y_ppem_substitute;

  } TT_SBit_Scale;


  /*************************************************************/
  /*                                                           */
  /* <Struct> TT_SBit_Image                                    */
  /*                                                           */
  /* <Description>                                             */
  /*    A structure used to describe a given embedded bitmap   */
  /*    image.                                                 */
  /*                                                           */
  /* <Fields>                                                  */
  /*    map       :: bitmap descriptor                         */
  /*    bit_depth :: pixel bit depth                           */
  /*    metrics   :: glyph metrics for the bitmap              */
  /*                                                           */
  typedef struct  TT_SBit_Image_
  {
    TT_Raster_Map         map;
    int                   bit_depth;
    TT_Big_Glyph_Metrics  metrics;

  } TT_SBit_Image;


  /*************************************************************/
  /*                                                           */
  /* <Struct> TT_EBLC                                          */
  /*                                                           */
  /* <Description>                                             */
  /*    A structure used to describe the `EBLC' table from     */
  /*    a TrueType font.                                       */
  /*                                                           */
  /* <Fields>                                                  */
  /*    version     :: version number of the EBLC table        */
  /*                                                           */
  /*    num_strikes :: the number of strikes, i.e. bitmap      */
  /*                   sizes, present in this font             */
  /*                                                           */
  /*    strikes     :: array of strikes                        */
  /*                                                           */
  typedef struct  TT_EBLC_
  {
    TT_ULong         version;
    TT_ULong         num_strikes;
    TT_SBit_Strike*  strikes;

  } TT_EBLC;




  /*************************************************************/
  /*                                                           */
  /* <Function>                                                */
  /*    TT_Init_SBit_Extension                                 */
  /*                                                           */
  /* <Description>                                             */
  /*    Initializes the embedded bitmap extension for the      */
  /*    FreeType engine.                                       */
  /*                                                           */
  /* <Input>                                                   */
  /*    engine :: handle to current FreeType library instance  */
  /*                                                           */
  /* <Return>                                                  */
  /*    Error code.  0 means success.                          */
  /*                                                           */
  EXPORT_DEF
  TT_Error  TT_Init_SBit_Extension( TT_Engine  engine );


  /*************************************************************/
  /*                                                           */
  /* <Function>                                                */
  /*    TT_Get_Face_Bitmaps                                    */
  /*                                                           */
  /* <Description>                                             */
  /*    Loads the `EBLC' table from a font file, if any.       */
  /*                                                           */
  /* <Input>                                                   */
  /*    face :: handle to the source TrueType font/face        */
  /*                                                           */
  /* <Output>                                                  */
  /*    eblc_table :: a descriptor for the EBLC table          */
  /*                                                           */
  /* <Return>                                                  */
  /*    Error code. 0 means success.                           */
  /*                                                           */
  /* <Note>                                                    */
  /*    This function returns TT_Err_Table_Missing if the      */
  /*    font contains no embedded bitmaps.  All fields in      */
  /*    `eblc_table' will then be set to 0.                    */
  /*                                                           */
  EXPORT_DEF
  TT_Error  TT_Get_Face_Bitmaps( TT_Face   face,
                                 TT_EBLC*  eblc_table );


  /*************************************************************/
  /*                                                           */
  /* <Function>                                                */
  /*    TT_New_SBit_Image                                      */
  /*                                                           */
  /* <Description>                                             */
  /*    Allocates a new embedded bitmap container.             */
  /*                                                           */
  /* <Output>                                                  */
  /*    image :: sbit image                                    */
  /*                                                           */
  /* <Return>                                                  */
  /*    Error code.  0 means success.                          */
  /*                                                           */
  EXPORT_DEF
  TT_Error  TT_New_SBit_Image( TT_SBit_Image**  image );


  /*************************************************************/
  /*                                                           */
  /* <Function>                                                */
  /*    TT_Done_SBit_Image                                     */
  /*                                                           */
  /* <Description>                                             */
  /*    Releases an embedded bitmap container.                 */
  /*                                                           */
  /* <Input>                                                   */
  /*    image :: sbit image                                    */
  /*                                                           */
  EXPORT_DEF
  void  TT_Done_SBit_Image( TT_SBit_Image*  image );


  /*************************************************************/
  /*                                                           */
  /*  <Function> TT_Get_SBit_Strike                            */
  /*                                                           */
  /*  <Description>                                            */
  /*     Loads a suitable strike (bitmap sizetable) for the    */
  /*     given instance.  This strike includes                 */
  /*     sbitLineMetrics.                                      */
  /*                                                           */
  /*  <Input>                                                  */
  /*     face     :: the source face                           */
  /*     instance :: the current size instance                 */
  /*                                                           */
  /*  <Output>                                                 */
  /*     strike   :: the bitmap strike descriptor              */
  /*                                                           */
  /*  <Return>                                                 */
  /*     Error code.  0 means success.                         */
  /*                                                           */
  EXPORT_DEF
  TT_Error  TT_Get_SBit_Strike( TT_Face          face,
                                TT_Instance      instance,
                                TT_SBit_Strike*  strike );


  /*************************************************************/
  /*                                                           */
  /* <Function>                                                */
  /*    TT_Load_Glyph_Bitmap                                   */
  /*                                                           */
  /* <Description>                                             */
  /*    Loads a given glyph embedded bitmap.                   */
  /*                                                           */
  /* <Input>                                                   */
  /*    face        :: handle to the source TrueType font/face */
  /*    instance    :: current size/transform instance         */
  /*    glyph_index :: index of source glyph                   */
  /*    bitmap      :: target embedded bitmap descriptor       */
  /*                                                           */
  /* <Return>                                                  */
  /*    Error code.  0 means success.                          */
  /*                                                           */
  /* <Note>                                                    */
  /*    This function returns an error if there is no          */
  /*    embedded bitmap for the glyph at the given             */
  /*    instance.                                              */
  /*                                                           */
  EXPORT_DEF
  TT_Error  TT_Load_Glyph_Bitmap( TT_Face         face,
                                  TT_Instance     instance,
                                  TT_UShort       glyph_index,
                                  TT_SBit_Image*  bitmap );

#ifdef __cplusplus
}
#endif

#endif /* FTXSBIT_H */


/* END */