Retrieving the Device Context for a Surface (Windows CE 5.0)
If you want to modify the contents of a DirectDraw surface object by using GDI functions, you must retrieve a GDI-compatible device context handle.
This could be useful if you wanted to display text in a DirectDraw surface by calling the DrawText Win32 function, which accepts a handle to a device context as a parameter.
It is possible to retrieve a GDI-compatible device context for a surface by calling the IDirectDrawSurface5::GetDC method for that surface.
The following example shows how this might be done.
// For this example the lpDDS4 variable is a valid pointer
// to an IDirectDrawSurface5 interface.
HDC hdc;
HRESULT HR;
hr = lpDDS4->GetDC(&hdc);
if(FAILED(hr))
return hr;
// Call DrawText, or some other GDI
// function here.
lpDDS4->ReleaseDC(hdc);
Note that the code calls the IDirectDrawSurface5::ReleaseDC method when the surface's device context is no longer needed.
This step is required, because the IDirectDrawSurface5::GetDC method uses an internal version of the IDirectDrawSurface5::Lock method to lock the surface. The surface remains locked until the IDirectDrawSurface5::ReleaseDC method is called.
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