WGF finally branded as DirectX 10 - A WinCustomize Article by Brad Wardell
It gave some details to the developers officially about its upcoming API and we know that it plans to release this API together with Longhorn. Or Vista, as we must learn to call it.
The DirectX 10 API will have completely new and faster dynamic link libraries (DLLs) and is supposed to run much faster. The company decided to cut the backward compatibility with DirectX 9, 8, 7 and lower in this API but there will be a way to use games programmed for those APIs. Microsoft will enable support for DX 9 or lower games through a software layer, meaning it might run slower.
The company did this to make the next API faster, it said, and at the same time will take some burden of the CPU runtime. At the same time we learned that DirectX 10 will have support for Shaders beyond Shaders, model 4.0.
It's coming with Longhorn but we learned that Shader Model 4.0 might come even before Vista."