Construction
| CRgn | Constructs a CRgn object. | 
Initialization
| CreateRectRgn | Initializes a CRgn object with a rectangular region. | 
| CreateRectRgnIndirect | Initializes a CRgn object with a rectangular region defined by a RECT structure. | 
| CreateEllipticRgn | Initializes a CRgn object with an elliptical region. | 
| CreateEllipticRgnIndirect | Initializes a CRgn object with an elliptical region defined by a RECT structure. | 
| CreatePolygonRgn | Initializes a CRgn object with a polygonal region. The system closes the polygon automatically, if necessary, by drawing a line from the last vertex to the first. | 
| CreatePolyPolygonRgn | Initializes a CRgn object with a region consisting of a series of closed polygons. The polygons may be disjoint, or they may overlap. | 
| CreateRoundRectRgn | Initializes a CRgn object with a rectangular region with rounded corners. | 
| CombineRgn | Sets a CRgn object so that it is equivalent to the union of two specified CRgn objects. | 
| CopyRgn | Sets a CRgn object so that it is a copy of a specified CRgn object. | 
| CreateFromPath | Creates a region from the path that is selected into the given device context. | 
| CreateFromData | Creates a region from the given region and transformation data. | 
Operations
| EqualRgn | Checks two CRgn objects to determine whether they are equivalent. | 
| FromHandle | Returns a pointer to a CRgn object when given a handle to a Windows region. | 
| GetRegionData | Fills the specified buffer with data describing the given region. | 
| GetRgnBox | Retrieves the coordinates of the bounding rectangle of a CRgn object. | 
| OffsetRgn | Moves a CRgn object by the specified offsets. | 
| PtInRegion | Determines whether a specified point is in the region. | 
| RectInRegion | Determines whether any part of a specified rectangle is within the boundaries of the region. | 
| SetRectRgn | Sets the CRgn object to the specified rectangular region. | 
Operators
| operator HRGN | Returns the Windows handle contained in the CRgn object. |