DirectDraw Callback Support Using DrvEnableDirectDraw

The display driver can implement the DrvEnableDirectDraw function to indicate various DirectDraw callback support. To indicate support, the driver returns pointers to the DD_CALLBACKS, DD_SURFACECALLBACKS, and DD_PALETTECALLBACKS structures in the pCallBacks, pSurfaceCallBacks, and pPaletteCallBacks parameters.

The driver populates members of the DD_CALLBACKS structure to indicate that it supports the following callback functions.

Callback Function	Description
DdCanCreateSurface	Returns a value that indicates whether the driver can create a surface of the specified surface description.
DdCreatePalette	Creates a DirectDrawPalette object for the specified DirectDraw object.
DdCreateSurface	Creates a DirectDraw surface.
DdGetScanLine	Returns the number of the current physical scan line.
DdMapMemory	Maps application-modifiable portions of the frame buffer into the user-mode address space of the specified process, or it unmaps memory.
DdWaitForVerticalBlank	Returns the vertical blank status of the device.

The driver populates members of the DD_SURFACECALLBACKS structure to indicate that it supports the following callback functions.

Callback Function	Description
DdAddAttachedSurface	Attaches a surface to another surface.
DdBlt	Performs a bit-block transfer (blt) of display data from a source surface to a destination surface.
DdDestroySurface	Destroys a DirectDraw surface.
DdFlip	Causes the surface memory associated with the target surface to become the primary surface, and the current surface to become the nonprimary surface.
DdGetBltStatus	Queries the blt status of the specified surface.
DdGetFlipStatus	Determines whether the most recently requested flip on a surface has occurred.
DdLock	Locks a specified area of surface memory and provides a valid pointer to a block of memory associated with a surface.
DdSetColorKey	Sets the color key value for the specified surface.
DdSetOverlayPosition	Sets the position for an overlay.
DdSetPalette	Attaches a palette to the specified surface.
DdUnlock	Releases the lock held on the specified surface.
DdUpdateOverlay	Repositions or modifies the visual attributes of an overlay surface.

The driver populates members of the DD_PALETTECALLBACKS structure to indicate that it supports the following callback functions.

Callback Function	Description
DdDestroyPalette	Destroys the specified palette.
DdSetEntries	Updates the palette entries in the specified palette.