多边形求交集，实在是写不出来啊，求帮忙

[秦帅]

[赵4老师]

CombineRgn The CombineRgn function combines two regions and stores the result in a third region. The two regions are combined according to the specified mode. int CombineRgn( HRGN hrgnDest, // handle to destination region HRGN hrgnSrc1, // handle to source region HRGN hrgnSrc2, // handle to source region int fnCombineMode // region combining mode ); Parameters hrgnDest Handle to a new region with dimensions defined by combining two other regions. (This region must exist before CombineRgn is called.) hrgnSrc1 Handle to the first of two regions to be combined. hrgnSrc2 Handle to the second of two regions to be combined. fnCombineMode Specifies a mode indicating how the two regions will be combined. This parameter can be one of the following values: Value Description RGN_AND Creates the intersection of the two combined regions. RGN_COPY Creates a copy of the region identified by hrgnSrc1. RGN_DIFF Combines the parts of hrgnSrc1 that are not part of hrgnSrc2. RGN_OR Creates the union of two combined regions. RGN_XOR Creates the union of two combined regions except for any overlapping areas. Return Values The return value specifies the type of the resulting region. It can be one of the following values: Value Meaning NULLREGION The region is empty. SIMPLEREGION The region is a single rectangle. COMPLEXREGION The region is more than a single rectangle. ERROR No region is created. Remarks The three regions need not be distinct. For example, the hrgnSrc1 parameter can equal the hrgnDest parameter. QuickInfo Windows NT: Requires version 3.1 or later. Windows: Requires Windows 95 or later. Windows CE: Requires version 1.0 or later. Header: Declared in wingdi.h. Import Library: Use gdi32.lib. See Also Regions Overview, Region Functions, CreateEllipticRgn, CreateEllipticRgnIndirect, CreatePolygonRgn, CreatePolyPolygonRgn, CreateRectRgn, CreateRectRgnIndirect, CreateRoundRectRgn