PFND3DDDI_CHECKDIRECTFLIPSUPPORT callback function

Description

Called by the Desktop Window Manager (DWM) to verify that the user-mode driver supports Direct Flip operations, in which video memory is seamlessly flipped between an application's managed primary allocations and the DWM's managed primary allocations.

Parameters

hDevice

A handle to the display device (graphics context).

unnamedParam2

pData [in, out]

A pointer to a D3DDDIARG_CHECKDIRECTFLIPSUPPORT structure that defines the parameters for the operation.

Return value

Returns S_OK or an appropriate error result if the operation is not successfully performed.

Remarks

This function is called at least once before the DWM attempts to present to a Direct Flip swapchain. It is also called after each mode change occurs, or after the DWM re-creates its own swapchain for any reason.

The user-mode driver should ensure that the managed primary allocations of the application and the DWM have the following compatible resources:

• Stereo resources.
• Multiple Sample Anti Aliasing (MSAA) formats.
• Swizzle formats. If the swizzle can only be changed at every VSync interval, ensure that the CheckDirectFlipFlags member of the D3DDDI_CHECK_DIRECT_FLIP_FLAGS structure does not have a value of D3D11_1DDI_CHECK_DIRECT_FLIP_IMMEDIATE.
• Both managed primary allocations should be created using the same VidPnSourceId value in the D3DDDI_ALLOCATIONINFO structure.
• Display adapter configurations are linked.

The user-mode driver might need to call the kernel-mode driver to perform these validations. To do this, call the pfnEscapeCb callback function and then call the DxgkCbGetHandleData function to access the kernel-mode driver's resource allocation data.

Because the DWM typically creates its own device using the highest possible Microsoft Direct3D feature level, the DWM will not call this function if the hardware supports a Direct3D device driver interface (DDI) that is greater than version 9.3. However, any Microsoft Direct3D 9 driver should implement this function to enable the Direct Flip user experience.

See also

D3DDDI_CHECK_DIRECT_FLIP_FLAGS

D3DDDI_DEVICEFUNCS