virtual void DrawArc( long x1, long y1, long x2, long y2, double xc, double yc );
virtual void DrawEllipticArc( long x, long y, long width, long height, double sa, double ea );
virtual void DrawPoint( long x, long y );
virtual void DrawArc( long x1, long y1, long x2, long y2, double xc, double yc );
virtual void DrawEllipticArc( long x, long y, long width, long height, double sa, double ea );
virtual void DrawPoint( long x, long y );