IDirectDrawSurface::SetClipper

A version of this page is also available for

Windows Embedded CE 6.0 R3

4/8/2010

This method attaches a Clipper object to or deletes one from a surface.

Syntax

HRESULT SetClipper(
  LPDIRECTDRAWCLIPPER lpDDClipper
); 

Parameters

• lpDDClipper
  Address of the IDirectDrawClipper interface for the DirectDrawClipper object that will be attached to the DirectDrawSurface object. If this parameter is NULL, the current DirectDrawClipper object will be detached.

Return Value

If the method succeeds, the return value is DD_OK.

If the method fails, the return value may be one of the following error values:

For more information on these error codes see DirectDraw Return Values.

Remarks

When setting a clipper to a surface for the first time, this method increments the clipper's reference count; subsequent calls do not affect the clipper's reference count.

If you pass NULL as the lpDDClipper parameter, the clipper is removed from the surface, and the clipper's reference count is decremented.

If you do not delete the clipper, the surface releases its reference to the clipper when the surface itself is released.

According to COM rules, your application is responsible for releasing references it holds to the clipper when the object is no longer needed.

This method is mainly used by surfaces that are being overlaid on or blitted to the primary surface. However, it can be used on any surface.

After a DirectDrawClipper object has been attached and a clip list is associated with it, the DirectDrawClipper object will be used for the IDirectDrawSurface::Blt and IDirectDrawSurface::UpdateOverlay operations involving the parent DirectDrawSurface object.

This method can also detach a DirectDrawSurface object's current DirectDrawClipper object.

Requirements

See Also

Reference

IDirectDrawSurface::GetClipper