ftoutln.h.svn-base

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  /*    outline :: A pointer to the target outline descriptor.             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    This functions toggles the bit flag @FT_OUTLINE_REVERSE_FILL in    */
  /*    the outline's `flags' field.                                       */
  /*                                                                       */
  /*    It shouldn't be used by a normal client application, unless it     */
  /*    knows what it is doing.                                            */
  /*                                                                       */
  FT_EXPORT( void )
  FT_Outline_Reverse( FT_Outline*  outline );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Get_Bitmap                                              */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Render an outline within a bitmap.  The outline's image is simply  */
  /*    OR-ed to the target bitmap.                                        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    library :: A handle to a FreeType library object.                  */
  /*                                                                       */
  /*    outline :: A pointer to the source outline descriptor.             */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    abitmap :: A pointer to the target bitmap descriptor.              */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0~means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    This function does NOT CREATE the bitmap, it only renders an       */
  /*    outline image within the one you pass to it!  Consequently, the    */
  /*    various fields in `abitmap' should be set accordingly.             */
  /*                                                                       */
  /*    It will use the raster corresponding to the default glyph format.  */
  /*                                                                       */
  /*    The value of the `num_grays' field in `abitmap' is ignored.  If    */
  /*    you select the gray-level rasterizer, and you want less than 256   */
  /*    gray levels, you have to use @FT_Outline_Render directly.          */
  /*                                                                       */
  FT_EXPORT( FT_Error )
  FT_Outline_Get_Bitmap( FT_Library        library,
                         FT_Outline*       outline,
                         const FT_Bitmap  *abitmap );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Render                                                  */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Render an outline within a bitmap using the current scan-convert.  */
  /*    This functions uses an @FT_Raster_Params structure as an argument, */
  /*    allowing advanced features like direct composition, translucency,  */
  /*    etc.                                                               */
  /*                                                                       */
  /* <Input>                                                               */
  /*    library :: A handle to a FreeType library object.                  */
  /*                                                                       */
  /*    outline :: A pointer to the source outline descriptor.             */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    params  :: A pointer to an @FT_Raster_Params structure used to     */
  /*               describe the rendering operation.                       */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0~means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    You should know what you are doing and how @FT_Raster_Params works */
  /*    to use this function.                                              */
  /*                                                                       */
  /*    The field `params.source' will be set to `outline' before the scan */
  /*    converter is called, which means that the value you give to it is  */
  /*    actually ignored.                                                  */
  /*                                                                       */
  /*    The gray-level rasterizer always uses 256 gray levels.  If you     */
  /*    want less gray levels, you have to provide your own span callback. */
  /*    See the @FT_RASTER_FLAG_DIRECT value of the `flags' field in the   */
  /*    @FT_Raster_Params structure for more details.                      */
  /*                                                                       */
  FT_EXPORT( FT_Error )
  FT_Outline_Render( FT_Library         library,
                     FT_Outline*        outline,
                     FT_Raster_Params*  params );


 /**************************************************************************
  *
  * @enum:
  *   FT_Orientation
  *
  * @description:
  *   A list of values used to describe an outline's contour orientation.
  *
  *   The TrueType and PostScript specifications use different conventions
  *   to determine whether outline contours should be filled or unfilled.
  *
  * @values:
  *   FT_ORIENTATION_TRUETYPE ::
  *     According to the TrueType specification, clockwise contours must
  *     be filled, and counter-clockwise ones must be unfilled.
  *
  *   FT_ORIENTATION_POSTSCRIPT ::
  *     According to the PostScript specification, counter-clockwise contours
  *     must be filled, and clockwise ones must be unfilled.
  *
  *   FT_ORIENTATION_FILL_RIGHT ::
  *     This is identical to @FT_ORIENTATION_TRUETYPE, but is used to
  *     remember that in TrueType, everything that is to the right of
  *     the drawing direction of a contour must be filled.
  *
  *   FT_ORIENTATION_FILL_LEFT ::
  *     This is identical to @FT_ORIENTATION_POSTSCRIPT, but is used to
  *     remember that in PostScript, everything that is to the left of
  *     the drawing direction of a contour must be filled.
  *
  *   FT_ORIENTATION_NONE ::
  *     The orientation cannot be determined.  That is, different parts of
  *     the glyph have different orientation.
  *
  */
  typedef enum  FT_Orientation_
  {
    FT_ORIENTATION_TRUETYPE   = 0,
    FT_ORIENTATION_POSTSCRIPT = 1,
    FT_ORIENTATION_FILL_RIGHT = FT_ORIENTATION_TRUETYPE,
    FT_ORIENTATION_FILL_LEFT  = FT_ORIENTATION_POSTSCRIPT,
    FT_ORIENTATION_NONE

  } FT_Orientation;


 /**************************************************************************
  *
  * @function:
  *   FT_Outline_Get_Orientation
  *
  * @description:
  *   This function analyzes a glyph outline and tries to compute its
  *   fill orientation (see @FT_Orientation).  This is done by computing
  *   the direction of each global horizontal and/or vertical extrema
  *   within the outline.
  *
  *   Note that this will return @FT_ORIENTATION_TRUETYPE for empty
  *   outlines.
  *
  * @input:
  *   outline ::
  *     A handle to the source outline.
  *
  * @return:
  *   The orientation.
  *
  */
  FT_EXPORT( FT_Orientation )
  FT_Outline_Get_Orientation( FT_Outline*  outline );


  /* */


FT_END_HEADER

#endif /* __FTOUTLN_H__ */


/* END */


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