### IDirectDraw2::GetScanLine

The IDirectDraw2::GetScanLine method retrieves the scan line that is currently being drawn on the monitor.

HRESULT GetScanLine(

LPDWORD lpdwScanLine

);

##### Parameters

lpdwScanLine
  Address of the variable that will contain the scan line the display is currently on.

##### Return Values

If the method succeeds, the return value is DD_OK.

If the method fails, the return value may be one of the following error values:

DDERR_INVALIDOBJECT
DDERR_INVALIDPARAMS
DDERR_UNSUPPORTED
DDERR_VERTICALBLANKINPROGRESS

##### Remarks

Scan lines are reported as zero-based integers. The returned scan line value is between 0 and n, where scan line 0 is the first visible scan line on the screen and n is the last visible scan line, plus any scan lines that occur during vblank. So, in a case where an application is running at 640480, and there are 12 scan lines during vblank, the values returned by this method will range from 0 to 491.

##### See Also

IDirectDraw2::GetVerticalBlankStatus, IDirectDraw2::WaitForVerticalBlank