DirectX SDK

IDirectDraw7::WaitForVerticalBlank

The IDirectDraw7::WaitForVerticalBlank method helps the application synchronize itself with the vertical-blank interval.

HRESULT WaitForVerticalBlank(
  DWORD dwFlags, 
  HANDLE hEvent  
);

Parameters

dwFlags
Determines how long to wait for the vertical blank. One of the following flags:
DDWAITVB_BLOCKBEGIN
Returns when the vertical-blank interval begins.
DDWAITVB_BLOCKBEGINEVENT
Triggers an event when the vertical blank begins. This value is not currently supported.
DDWAITVB_BLOCKEND
Returns when the vertical-blank interval ends and the display begins.
hEvent
Handle of the event to be triggered when the vertical blank begins. This parameter is not currently used.

Return Values

If the method succeeds, the return value is DD_OK.

If it fails, the method can return one of the following error values:

DDERR_INVALIDOBJECT
DDERR_INVALIDPARAMS
DDERR_UNSUPPORTED
DDERR_WASSTILLDRAWING

Requirements

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 98.
  Header: Declared in ddraw.h.

See Also

IDirectDraw7::GetVerticalBlankStatus, IDirectDraw7::GetScanLine