Inside Macintosh: QuickDraw GX Objects /

Chapter 6 - Transform Objects / Transform Objects Reference

Constants and Data Types

Shape Parts for Hit-Testing

Each transform object specifies the parts of a shape on which hit-testing is performed. The choices are specified by the gxShapeParts enumeration. For determining distance to a hit part, the hit-testing functions evaluate shape parts in the order shown in the enumeration.

enum gxShapeParts {      /* (in order of evaluation) */
   gxNoPart             = 0,   
   gxBoundsPart         = 0x0001,
   gxGeometryPart       = 0x0002,
   gxPenPart            = 0x0004,
   gxCornerPointPart    = 0x0008,
   gxControlPointPart   = 0x0010,
   gxEdgePart           = 0x0020,
   gxJoinPart           = 0x0040,
   gxStartCapPart       = 0x0080,
   gxEndCapPart         = 0x0100,
   gxDashPart           = 0x0200,
   gxPatternPart        = 0x0400,
   gxGlyphBoundsPart    = gxJoinPart,
   gxGlyphFirstPart     = gxStartCapPart,
   gxGlyphLastPart      = gxEndCapPart,
   gxSideBearingPart    = gxDashPart,
   gxAnyPart            = gxBoundsPart | gxGeometryPart | 
            gxPenPart | gxCornerPointPart | gxControlPointPart | 
            gxEdgePart | gxJoinPart | gxStartCapPart | 
            gxEndCapPart | gxDashPart | gxPatternPart 
} ;

typedef long gxShapePart;

The individual shape parts are described in Table 6-1 on page 6-12.