IDirectDrawSurface::UpdateOverlayZOrder

HRESULT UpdateOverlayZOrder(DWORD dwFlags,

LPDIRECTDRAWSURFACE lpDDSReference);

Sets the z-order of an overlay. The z-order determines which overlay should be occluded when multiple overlays are displayed simultaneously. Overlay positions are all relative to other overlays — there is no true z-value for them.

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

DDERR_INVALIDOBJECT DDERR_INVALIDPARAMS

DDERR_NOTAOVERLAYSURFACE

dwFlags

DDOVERZ_INSERTINBACKOF

Inserts this overlay in the overlay chain behind the reference overlay.

DDOVERZ_INSERTINFRONTOF

Inserts this overlay in the overlay chain in front of the reference overlay.

DDOVERZ_MOVEBACKWARD

Moves this overlay one position backward in the overlay chain.

DDOVERZ_MOVEFORWARD

Moves this overlay one position forward in the overlay chain.

DDOVERZ_SENDTOBACK

Moves this overlay to the back of the overlay chain.

DDOVERZ_SENDTOFRONT

Moves this overlay to the front of the overlay chain.

lpDDSReference

Address of the DirectDrawSurface structure that represents the DirectDrawSurface to be used as a relative position in the overlay chain. This parameter is needed only for DDOVERZ_INSERTINBACKOF and DDOVERZ_INSERTINFRONTOF.