Microsoft DirectX 9.0 |
The UpdateOverlayZOrder method sets the z order of an overlay. The z order is used to determine which overlay should be occluded when multiple overlays are being displayed simultaneously. Overlay positions are all relative to other overlays -- there is no true z value for them.
Syntax
HRESULT UpdateOverlayZOrder(
DWORD dwFlags,
LPDIRECTDRAWSURFACE lpDDSReference
);
Parameters
dwFlags
Zero or more of the following flags.
Value | Description |
DDOVERZ_INSERTINBACKOF | Insert this overlay in the overlay chain in back of the overlay specified as the reference overlay. |
DDOVERZ_INSERTINFRONTOF | Insert this overlay in the overlay chain in front of the overlay specified as the reference overlay. |
DDOVERZ_MOVEBACKWARD | Move this overlay one overlay position backward. |
DDOVERZ_MOVEFORWARD | Move this overlay one overlay position forward. |
DDOVERZ_SENDTOBACK | Move this overlay to the back of the overlay chain. |
DDOVERZ_SENDTOFRONT | Move this overlay to the front of the overlay chain. |
lpDDSReference
Points to the IDirectDrawSurface interface of the surface that should be used as a relative position in the overlay chain. This parameter is needed only for DDOVERZ_INSERTINBACKOF and DDOVERZ_INSERTINFRONTOF.
Return Values
Value | Description |
DD_OK | The method succeeded. |
DDERR_INVALIDOBJECT | DirectDraw received a pointer that was an invalid DirectDraw object. |
DDERR_INVALIDPARAMS | One or more of the input parameters is invalid. |
DDERR_NOTAOVERLAYSURFACE | Returned when an overlay method is called for a non-overlay surface. |
See Also