extern static IntPtr CGPatternCreate(IntPtr info, RectangleF bounds, CGAffineTransform matrix, float xStep, float yStep, CGPatternTiling tiling, bool isColored, ref CGPatternCallbacks callbacks);
extern static IntPtr CGPatternCreate(IntPtr info, RectangleF bounds, CGAffineTransform matrix, float xStep, float yStep, CGPatternTiling tiling, bool isColored, ref CGPatternCallbacks callbacks);