DDOVERLAYFX

The DDOVERLAYFX structure passes override information to the IDirectDrawSurface3::UpdateOverlay method.

typedef struct _DDOVERLAYFX{ 
    DWORD dwSize; 
    DWORD dwAlphaEdgeBlendBitDepth; 
    DWORD dwAlphaEdgeBlend; 
    DWORD dwReserved; 
    DWORD dwAlphaDestConstBitDepth; 
union 
{ 
        DWORD               dwAlphaDestConst; 
        LPDIRECTDRAWSURFACE lpDDSAlphaDest; 
}; 
    DWORD dwAlphaSrcConstBitDepth; 
union 
{ 
        DWORD               dwAlphaSrcConst; 
        LPDIRECTDRAWSURFACE lpDDSAlphaSrc; 
}; 
    DDCOLORKEY dckDestColorkey; 
    DDCOLORKEY dckSrcColorkey; 
 
    DWORD dwDDFX; 
    DWORD dwFlags; 
} DDOVERLAYFX,FAR *LPDDOVERLAYFX; 
 

Members

dwSize
Size of the structure, in bytes. This members must be initialized before the structure is used.
dwAlphaEdgeBlendBitDepth
Bit depth used to specify the constant for an alpha edge blend.
dwAlphaEdgeBlend
Constant to use as the alpha for an edge blend.
dwReserved
Reserved for future use.
dwAlphaDestConstBitDepth
Bit depth used to specify the alpha constant for a destination.
dwAlphaDestConst
Constant to use as the alpha channel for a destination.
lpDDSAlphaDest
Address of a surface to use as the alpha channel for a destination.
dwAlphaSrcConstBitDepth
Bit depth used to specify the alpha constant for a source.
dwAlphaSrcConst
Constant to use as the alpha channel for a source.
lpDDSAlphaSrc
Address of a surface to use as the alpha channel for a source.
dckDestColorkey
Destination color key override.
dckSrcColorkey
Source color key override.
dwDDFX
Overlay FX flags.
DDOVERFX_ARITHSTRETCHY
If stretching, use arithmetic stretching along the y-axis for this overlay.
DDOVERFX_MIRRORLEFTRIGHT
Mirror the overlay around the vertical axis.
DDOVERFX_MIRRORUPDOWN
Mirror the overlay around the horizontal axis.

dwFlags
This member is currently not used and must be set to 0.

QuickInfo

  Windows NT: Use version 4.0 or later.
  Windows: Use Windows 95 or later. Available as a redistributable for Windows 95.
  Windows CE: Unsupported.
  Header: Declared in ddraw.h.