inline wxPoint2DInt operator-(const wxPoint2DInt& pt1 , const wxPoint2DInt& pt2);
inline wxPoint2DInt operator*(const wxPoint2DInt& pt1 , const wxPoint2DInt& pt2);
inline wxPoint2DInt operator*(wxInt32 n , const wxPoint2DInt& pt);
inline wxPoint2DInt operator-(const wxPoint2DInt& pt1 , const wxPoint2DInt& pt2);
inline wxPoint2DInt operator*(const wxPoint2DInt& pt1 , const wxPoint2DInt& pt2);
inline wxPoint2DInt operator*(wxInt32 n , const wxPoint2DInt& pt);