|Microsoft DirectX 9.0|
The GetScanLine method returns the scan line that the monitor is currently updating to the display.
HRESULT GetScanLine( LPDWORD lpdwScanLine );
Points to the DWORD that will contain the scan line the display is currently on.
|DD_OK||The method succeeded.|
|DDERR_INVALIDOBJECT||DirectDraw received a pointer that was an invalid DirectDraw object.|
|DDERR_INVALIDPARAMS||One or more of the input parameters is invalid.|
|DDERR_UNSUPPORTED||Action not supported.|
|DDERR_VERTICALBLANKINPROGRESS||Vertical blank is in progress.|