| DirectX SDK | 
The IDirectDrawVideoPort::GetFieldPolarity method retrieves the polarity of a video field.
HRESULT GetFieldPolarity( LPBOOL lpbFieldPolarity );
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_VIDEONOTACTIVE | 
  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in dvp.h.
  Import Library: Use ddraw.lib.