freetype.h

一个Xpdf应用的例子

  /*    strike (i.e., a bitmap instance of the font for a given            */
  /*    resolution) in a fixed-size font face.  This is used for the       */
  /*    `available_sizes' field of the FT_Face_Properties structure.       */
  /*                                                                       */
  /* <Fields>                                                              */
  /*    height :: The character height in pixels.                          */
  /*                                                                       */
  /*    width  :: The character width in pixels.                           */
  /*                                                                       */
  typedef struct  FT_Bitmap_Size_
  {
    FT_Short  height;
    FT_Short  width;

  } FT_Bitmap_Size;


  /*************************************************************************/
  /*************************************************************************/
  /*                                                                       */
  /*                     O B J E C T   C L A S S E S                       */
  /*                                                                       */
  /*************************************************************************/
  /*************************************************************************/

  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Library                                                         */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a FreeType library instance.  Each `library' is        */
  /*    completely independent from the others; it is the `root' of a set  */
  /*    of objects like fonts, faces, sizes, etc.                          */
  /*                                                                       */
  /*    It also embeds a system object (see FT_System), as well as a       */
  /*    scan-line converter object (see FT_Raster).                        */
  /*                                                                       */
  /* <Note>                                                                */
  /*    Library objects are created through FT_Init_FreeType().            */
  /*                                                                       */
  typedef struct FT_LibraryRec_  *FT_Library;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Module                                                          */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given FreeType module object.  Each module can be a  */
  /*    font driver, a renderer, or anything else that provides services   */
  /*    to the formers.                                                    */
  /*                                                                       */
  typedef struct FT_ModuleRec_*  FT_Module;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Driver                                                          */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given FreeType font driver object.  Each font driver */
  /*    is able to create faces, sizes, glyph slots, and charmaps from the */
  /*    resources whose format it supports.                                */
  /*                                                                       */
  /*    A driver can support either bitmap, graymap, or scalable font      */
  /*    formats.                                                           */
  /*                                                                       */
  typedef struct FT_DriverRec_*  FT_Driver;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Renderer                                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given FreeType renderer.  A renderer is in charge of */
  /*    converting a glyph image to a bitmap, when necessary.  Each        */
  /*    supports a given glyph image format, and one or more target        */
  /*    surface depths.                                                    */
  /*                                                                       */
  typedef struct FT_RendererRec_*  FT_Renderer;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Face                                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given driver face object.  A face object contains    */
  /*    all the instance and glyph independent data of a font file         */
  /*    typeface.                                                          */
  /*                                                                       */
  /*    A face object is created from a resource object through the        */
  /*    new_face() method of a given driver.                               */
  /*                                                                       */
  typedef struct FT_FaceRec_*  FT_Face;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_Size                                                            */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given driver size object.  Such an object models the */
  /*    _resolution_ AND _size_ dependent state of a given driver face     */
  /*    size.                                                              */
  /*                                                                       */
  /*    A size object is always created from a given face object.  It is   */
  /*    discarded automatically by its parent face.                        */
  /*                                                                       */
  typedef struct FT_SizeRec_*  FT_Size;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_GlyphSlot                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given `glyph slot'.  A slot is a container where it  */
  /*    is possible to load any of the glyphs contained within its parent  */
  /*    face.                                                              */
  /*                                                                       */
  /*    A glyph slot is created from a given face object.  It is discarded */
  /*    automatically by its parent face.                                  */
  /*                                                                       */
  typedef struct FT_GlyphSlotRec_*  FT_GlyphSlot;


  /*************************************************************************/
  /*                                                                       */
  /* <Type>                                                                */
  /*    FT_CharMap                                                         */
  /*                                                                       */
  /* <Description>                                                         */
  /*    A handle to a given character map.  A charmap is used to translate */
  /*    character codes in a given encoding into glyph indexes for its     */
  /*    parent's face.  Some font formats may provide several charmaps per */
  /*    font.                                                              */
  /*                                                                       */
  /*    A charmap is created from a given face object.  It is discarded    */
  /*    automatically by its parent face.                                  */
  /*                                                                       */
  typedef struct FT_CharMapRec_*  FT_CharMap;


  /*************************************************************************/
  /*                                                                       */
  /* <Macro>                                                               */
  /*    FT_ENC_TAG                                                         */
  /*                                                                       */
  /* <Description>                                                         */
  /*    This macro converts four letter tags into an unsigned long.        */
  /*                                                                       */
#ifndef FT_ENC_TAG
#define FT_ENC_TAG( value, _x1, _x2, _x3, _x4 ) \
        value = ( ( (unsigned long)_x1 << 24 ) | \
                  ( (unsigned long)_x2 << 16 ) | \
                  ( (unsigned long)_x3 << 8  ) | \
                    (unsigned long)_x4         )
#endif /* FT_ENC_TAG */


  /*************************************************************************/
  /*                                                                       */
  /* <Enum>                                                                */
  /*    FT_Encoding                                                        */
  /*                                                                       */
  /* <Description>                                                         */
  /*    An enumeration used to specify encodings supported by charmaps.    */
  /*    Used in the FT_Select_Charmap() API function.                      */
  /*                                                                       */
  /* <Note>                                                                */
  /*    Because of 32-bit charcodes defined in Unicode (i.e., surrogates), */
  /*    all character codes must be expressed as FT_Longs.                 */
  /*                                                                       */
  /*    Other encodings might be defined in the future.                    */
  /*                                                                       */
  typedef enum  FT_Encoding_
  {
    FT_ENC_TAG( ft_encoding_none, 0, 0, 0, 0 ),

    FT_ENC_TAG( ft_encoding_symbol,  's', 'y', 'm', 'b' ),
    FT_ENC_TAG( ft_encoding_unicode, 'u', 'n', 'i', 'c' ),
    FT_ENC_TAG( ft_encoding_latin_2, 'l', 'a', 't', '2' ),
    FT_ENC_TAG( ft_encoding_sjis,    's', 'j', 'i', 's' ),
    FT_ENC_TAG( ft_encoding_gb2312,  'g', 'b', ' ', ' ' ),
    FT_ENC_TAG( ft_encoding_big5,    'b', 'i', 'g', '5' ),
    FT_ENC_TAG( ft_encoding_wansung, 'w', 'a', 'n', 's' ),
    FT_ENC_TAG( ft_encoding_johab,   'j', 'o', 'h', 'a' ),

    FT_ENC_TAG( ft_encoding_adobe_standard, 'A', 'D', 'O', 'B' ),
    FT_ENC_TAG( ft_encoding_adobe_expert,   'A', 'D', 'B', 'E' ),
    FT_ENC_TAG( ft_encoding_adobe_custom,   'A', 'D', 'B', 'C' ),

    FT_ENC_TAG( ft_encoding_apple_roman, 'a', 'r', 'm', 'n' )

  } FT_Encoding;


  /*************************************************************************/
  /*                                                                       */