Modifies the coordinates of the viewport origin relative to the coordinates of the current viewport origin.
virtual CPoint OffsetViewportOrg( int nWidth, int nHeight );
Specifies the number of device units to add to the current origin's x-coordinate.
Specifies the number of device units to add to the current origin's y-coordinate.
The previous viewport origin (in device coordinates) as a CPoint object.
Header: afxwin.h