Return Codes for Direct3D Driver Callbacks

The return value for all driver callbacks must always be one of the following values.

Value	Description
D3DHAL_CONTEXT_BAD	The context that was passed in was not valid.
DDHAL_DRIVER_HANDLED	The driver has performed the operation and returned a valid return code for that operation in the ddrval member of the structure passed to the driver's callback. If this code is DD_OK, Direct3D proceeds with the function. Otherwise, Direct3D returns the error code provided by the driver and aborts the function.
DDHAL_DRIVER_NOTHANDLED	The driver has no comment on the requested operation. If the driver is required to have implemented a particular callback, Direct3D reports an error condition. Otherwise, Direct3D handles the operation as if the driver callback had not been defined by executing the Direct3D device-independent implementation. Direct3D typically ignores any value returned in the ddrval member of that callback's parameter structure.
D3DHAL_OUTOFCONTEXTS	There are no more contexts are left in this process.

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