Oops I was a bit in a rush when I typed it. On Windows Direct3D is very different than in Wine. In Windows ddraw.dll / d3d8.dll / d3d9.dll / d3d10.dll generate to what I will call 'Direct3D instructions' which are implemented by display drivers. Inside the driver a small amount of code might be common between the drivers but at least Microsoft doesn't update the old dlls anymore. What we do in Wine is that we have very thin ddraw.dll / d3d8.dll / d3d9.dll / d3d10.dll which call WineD3D in which we have the majority of the code. This means that when we add support for new OpenGL extensions and when we optimize code we also improve support for older Direct3D versions. This doesn't happen on Windows.
