IDirectDrawSurface::UpdateOverlayDisplay

HRESULT UpdateOverlayDisplay(DWORD dwFlags);

Repaints the rectangles in the dirty rectangle list of all active overlays. This clears the dirty rectangle list. This method is for software emulation only—it does nothing if the hardware supports overlays.

·Returns DD_OK if successful, or one of the following error values otherwise:

DDERR_INVALIDOBJECT DDERR_INVALIDPARAMS

DDERR_UNSUPPORTED DDERR_INVALIDSURFACETYPE

dwFlags

Specifies the type of update to perform.

DDOVER_REFRESHDIRTYRECTS

Updates the overlay display using the list of dirty rectangles previously constructed for this destination. This clears the dirty rectangle list.

DDOVER_REFRESHALL

Ignores the dirty rectangle list and updates the overlay display completely. This clears the dirty rectangle list.