IDirect3DDevice9::TestCooperativeLevel method

Reports the current cooperative-level status of the Direct3D device for a windowed or full-screen application.


HRESULT TestCooperativeLevel(



This method has no parameters.

Return Value


If the method succeeds, the return value is D3D_OK, indicating that the device is operational and the calling application can continue. If the method fails, the return value can be one of the following values: D3DERR_DEVICELOST, D3DERR_DEVICENOTRESET, D3DERR_DRIVERINTERNALERROR.


If the device is lost but cannot be restored at the current time, IDirect3DDevice9::TestCooperativeLevel returns the D3DERR_DEVICELOST return code. This would be the case, for example, when a full-screen device has lost focus. If an application detects a lost device, it should pause and periodically call IDirect3DDevice9::TestCooperativeLevel until it receives a return value of D3DERR_DEVICENOTRESET. The application may then attempt to reset the device by calling IDirect3DDevice9::Reset and, if this succeeds, restore the necessary resources and resume normal operation. Note that IDirect3DDevice9::Present will return D3DERR_DEVICELOST if the device is either "lost" or "not reset".

A call to IDirect3DDevice9::TestCooperativeLevel will fail if called on a different thread than that used to create the device being reset.


Target Platform Windows
Header d3d9helper.h (include D3D9.h)
Library D3D9.lib

See Also