ftoutln.h

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  /*                                                                       */
  FT_EXPORT( FT_Error )
  FT_Outline_Done( FT_Library   library,
                   FT_Outline*  outline );


  FT_EXPORT( FT_Error )
  FT_Outline_Done_Internal( FT_Memory    memory,
                            FT_Outline*  outline );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Check                                                   */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Check the contents of an outline descriptor.                       */
  /*                                                                       */
  /* <Input>                                                               */
  /*    outline :: A handle to a source outline.                           */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0~means success.                             */
  /*                                                                       */
  FT_EXPORT( FT_Error )
  FT_Outline_Check( FT_Outline*  outline );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Get_CBox                                                */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Return an outline's `control box'.  The control box encloses all   */
  /*    the outline's points, including Bézier control points.  Though it  */
  /*    coincides with the exact bounding box for most glyphs, it can be   */
  /*    slightly larger in some situations (like when rotating an outline  */
  /*    which contains Bézier outside arcs).                               */
  /*                                                                       */
  /*    Computing the control box is very fast, while getting the bounding */
  /*    box can take much more time as it needs to walk over all segments  */
  /*    and arcs in the outline.  To get the latter, you can use the       */
  /*    `ftbbox' component which is dedicated to this single task.         */
  /*                                                                       */
  /* <Input>                                                               */
  /*    outline :: A pointer to the source outline descriptor.             */
  /*                                                                       */
  /* <Output>                                                              */
  /*    acbox   :: The outline's control box.                              */
  /*                                                                       */
  FT_EXPORT( void )
  FT_Outline_Get_CBox( const FT_Outline*  outline,
                       FT_BBox           *acbox );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Translate                                               */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Apply a simple translation to the points of an outline.            */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    outline :: A pointer to the target outline descriptor.             */
  /*                                                                       */
  /* <Input>                                                               */
  /*    xOffset :: The horizontal offset.                                  */
  /*                                                                       */
  /*    yOffset :: The vertical offset.                                    */
  /*                                                                       */
  FT_EXPORT( void )
  FT_Outline_Translate( const FT_Outline*  outline,
                        FT_Pos             xOffset,
                        FT_Pos             yOffset );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Copy                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Copy an outline into another one.  Both objects must have the      */
  /*    same sizes (number of points & number of contours) when this       */
  /*    function is called.                                                */
  /*                                                                       */
  /* <Input>                                                               */
  /*    source :: A handle to the source outline.                          */
  /*                                                                       */
  /* <Output>                                                              */
  /*    target :: A handle to the target outline.                          */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0~means success.                             */
  /*                                                                       */
  FT_EXPORT( FT_Error )
  FT_Outline_Copy( const FT_Outline*  source,
                   FT_Outline        *target );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Transform                                               */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Apply a simple 2x2 matrix to all of an outline's points.  Useful   */
  /*    for applying rotations, slanting, flipping, etc.                   */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    outline :: A pointer to the target outline descriptor.             */
  /*                                                                       */
  /* <Input>                                                               */
  /*    matrix  :: A pointer to the transformation matrix.                 */
  /*                                                                       */
  /* <Note>                                                                */
  /*    You can use @FT_Outline_Translate if you need to translate the     */
  /*    outline's points.                                                  */
  /*                                                                       */
  FT_EXPORT( void )
  FT_Outline_Transform( const FT_Outline*  outline,
                        const FT_Matrix*   matrix );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Embolden                                                */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Embolden an outline.  The new outline will be at most 4~times      */
  /*    `strength' pixels wider and higher.  You may think of the left and */
  /*    bottom borders as unchanged.                                       */
  /*                                                                       */
  /*    Negative `strength' values to reduce the outline thickness are     */
  /*    possible also.                                                     */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    outline  :: A handle to the target outline.                        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    strength :: How strong the glyph is emboldened.  Expressed in      */
  /*                26.6 pixel format.                                     */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0~means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    The used algorithm to increase or decrease the thickness of the    */
  /*    glyph doesn't change the number of points; this means that certain */
  /*    situations like acute angles or intersections are sometimes        */
  /*    handled incorrectly.                                               */
  /*                                                                       */
  /*    Example call:                                                      */
  /*                                                                       */
  /*    {                                                                  */
  /*      FT_Load_Glyph( face, index, FT_LOAD_DEFAULT );                   */
  /*      if ( face->slot->format == FT_GLYPH_FORMAT_OUTLINE )             */
  /*        FT_Outline_Embolden( &face->slot->outline, strength );         */
  /*    }                                                                  */
  /*                                                                       */
  FT_EXPORT( FT_Error )
  FT_Outline_Embolden( FT_Outline*  outline,
                       FT_Pos       strength );


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    FT_Outline_Reverse                                                 */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Reverse the drawing direction of an outline.  This is used to      */
  /*    ensure consistent fill conventions for mirrored glyphs.            */
  /*                                                                       */
  /* <InOut>                                                               */