IDirectDraw4::GetScanLine

The IDirectDraw4::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 drawing.

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:

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 the vertical blank period. So, in a case where an application is running at 640×480, and there are 12 scan lines during vblank, the values returned by this method will range from 0 to 491.

QuickInfo

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in ddraw.h.
  Import Library: Use ddraw.lib.

See Also

IDirectDraw4::GetVerticalBlankStatus, IDirectDraw4::WaitForVerticalBlank