class CRgn : public CGdiObject

The CRgn class encapsulates a Windows graphical design interface (GDI) region. A region is an elliptical or polygonal area within a window. To use regions, you use the member functions of class CRgn in conjunction with the clipping functions defined as members of class CDC.

The member functions of CRgn create, alter, and retrieve information about the region object for which they are called.