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DD_DXAPI_OPENDIRECTDRAW control code

A video capture driver passes DD_DXAPI_OPENDIRECTDRAW in the dwFunctionNum parameter of the DxApi function to notify the kernel-mode video transport that the driver requires a DirectDraw object.

Input Parameters

  • lpvInBuffer
    Pointer to a DDOPENDIRECTDRAWIN structure that contains the DirectDraw handle information.

Output Parameters

  • lpvOutBuffer
    Pointer to a DDOPENDIRECTDRAWOUT structure that contains the new DirectDraw handle information.

Remarks

The object is specified by the dwDirectDrawHandle member of DDOPENDIRECTDRAWIN, which is the handle passed down from user mode. The driver must also specify a callback that is called if the DirectDraw object goes away. The pContext member of DDOPENDIRECTDRAWIN contains a value that is passed if the pfnDirectDrawClose callback is ever called.

If the ddRVal member of DDOPENDIRECTDRAWOUT is set to DD_OK, the output from this function identifier is a new DirectDraw handle. This new handle must be used on all subsequent calls that require a DirectDraw handle.

This function identifier can only be called from PASSIVE_LEVEL.

Requirements

Header file: Ddkmapi.h (include Ddkmapi.h)

See also

DDOPENDIRECTDRAWIN

DDOPENDIRECTDRAWOUT

NotifyCallback