virtual void DoSetClippingRegionAsRegion(const wxRegion& region) = 0;
virtual void DoSetClippingRegion(long x, long y,
long width, long height) = 0;
virtual void DoSetClippingRegionAsRegion(const wxRegion& region) = 0;
virtual void DoSetClippingRegion(long x, long y,
long width, long height) = 0;