IDirectDraw4::SetCooperativeLevel

The IDirectDraw4::SetCooperativeLevel method determines the top-level behavior of the application.

HRESULT SetCooperativeLevel(
  HWND hWnd,     
  DWORD dwFlags  
);

Parameters

hWnd

Window handle used for the application. Set to the calling application's top-level window handle (not a handle for any child windows created by the top-level window). This parameter can be NULL when the DDSCL_NORMAL flag is specified in the dwFlags parameter.

dwFlags

One or more of the following flags:

DDSCL_ALLOWMODEX: Allows the use of Mode X display modes. This flag can only be used if the DDSCL_EXCLUSIVE and DDSCL_FULLSCREEN flags are present.
DDSCL_ALLOWREBOOT: Allows CTRL+ALT+DEL to function while in exclusive (full-screen) mode.
DDSCL_CREATEDEVICEWINDOW: This flag is supported in Windows 98 and Windows 2000 only. Indicates that DirectDraw is to create and manage a default device window for this DirectDraw object. For more information, see Focus and Device Windows.
DDSCL_EXCLUSIVE: Requests the exclusive level. This flag must be used with the DDSCL_FULLSCREEN flag.
DDSCL_FPUSETUP: Indicates that the calling application is likely to keep the FPU set up for optimal Direct3D performance (single precision and exceptions disabled) so Direct3D does not need to explicitly set the FPU each time. For more information, see DirectDraw Cooperative Levels and FPU Precision.
DDSCL_FULLSCREEN: Indicates that the exclusive-mode owner will be responsible for the entire primary surface. GDI can be ignored. This flag must be used with the DDSCL_EXCLUSIVE flag.
DDSCL_MULTITHREADED: Requests multithread-safe DirectDraw behavior. This causes Direct3D to take the global critical section more frequently.
DDSCL_NORMAL: Indicates that the application will function as a regular Windows application. This flag cannot be used with the DDSCL_ALLOWMODEX, DDSCL_EXCLUSIVE, or DDSCL_FULLSCREEN flags.
DDSCL_NOWINDOWCHANGES: Indicates that DirectDraw is not allowed to minimize or restore the application window on activation.
DDSCL_SETDEVICEWINDOW: This flag is supported in Windows 98 and Windows 2000 only. Indicates that the hWnd parameter is the window handle of the device window for this DirectDraw object. This flag cannot be used with the DDSCL_SETFOCUSWINDOW flag.
DDSCL_SETFOCUSWINDOW: This flag is supported in Windows 98 and Windows 2000 only. Indicates that the hWnd parameter is the window handle of the focus window for this DirectDraw object. This flag cannot be used with the DDSCL_SETDEVICEWINDOW flag.

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_EXCLUSIVEMODEALREADYSET

Remarks

This method must be called by the same thread that created the application window.

An application must set either the DDSCL_EXCLUSIVE or DDSCL_NORMAL flag.

The DDSCL_EXCLUSIVE flag must be set to call functions that can have drastic performance consequences for other applications. For more information, see Cooperative Levels.

Interaction between this method and the IDirectDraw4::SetDisplayMode method differs from their IDirectDraw counterparts. For more information, see Restoring Display Modes.

Developers using Microsoft Foundation Classes (MFC) should keep in mind that the window handle passed to this method should identify the application's top-level window, not a derived child window. To retrieve your MFC application's top level window handle, you could use the following code:

    HWND hwndTop = AfxGetMainWnd()->GetSafeHwnd();

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.

IDirectDraw4::SetCooperativeLevel

Parameters

Return Values

Remarks

QuickInfo

See Also