int SelectClipRgn( CRgn* pRgn );
pRgn
Identifies the region to be selected.
Selects the given region as the current clipping region for the specified device context. Only a copy of the selected region is used. The region itself can be selected for any number of other device contexts, or it can be deleted.
The function assumes that the coordinates for the given region are specified in device units. Some printer devices support graphics at lower resolutions than text output to increase speed, but at the expense of quality. These devices scale coordinates for graphics so that one graphics device point corresponds to two or four true device points. This scaling factor affects clipping. If a region will be used to clip graphics, its coordinates must be divided down by the scaling factor. If the region will be used to clip text, no scaling adjustment is needed. The scaling factor is determined by using the GETSCALINGFACTOR printer escape.
The region's type. It can be any one of the following values:
| Value | Meaning |
| COMPLEXREGION | New clipping region has overlapping borders. |
| ERROR | Device context or region handle is not valid. |
| NULLREGION | New clipping region is empty. |
| SIMPLEREGION | New clipping region has no overlapping borders. |
CDC::Escape, CRgn, ::SelectClipRgn