int CombineRgn( CRgn* pRgn1, CRgn* pRgn2, int nCombineMode );
pRgn1
Identifies an existing region.
pRgn2
Identifies an existing region.
nCombineMode
Specifies the operation to be performed when combining the two source regions. It can be any one of the following values:
| Value | Meaning |
| RGN_AND | Uses overlapping areas of both regions (intersection). |
| RGN_COPY | Creates a copy of region 1 (identified by pRgn1). |
| RGN_DIFF | Creates a region consisting of the areas of region 1 (identified by pRgn1) that are not part of region 2 (identified by pRgn2). |
| RGN_OR | Combines both regions in their entirety (union). |
| RGN_XOR | Combines both regions but removes overlapping areas. |
Creates a new GDI region by combining two existing regions. The regions are combined as specified by nCombineMode.
The two specified regions are combined, and the resulting region handle is stored in the CRgn object. Thus, whatever region is stored in the CRgn object is replaced by the combined region.
Note:
Use CopyRgn to simply copy one region into another region.
Specifies the type of the resulting region. It can be one of the following values:
| Value | Meaning |
| COMPLEXREGION | New region has overlapping borders. |
| ERROR | No new region created. |
| NULLREGION | New region is empty. |
| SIMPLEREGION | New region has no overlapping borders. |
CRgn::CopyRgn, ::CombineRgn