Microsoft officially announces DirectX 11
Microsoft announced version eleven of DirectX at the Gamefest 2008.
Gamasutra reports DircetX 11 to be exclusive to Windows Vista, just like DX 10 is, but also to "future versions of Windows” (Windows 7). Therefore those people using XP are ignored again.
The three big improvements of DirectX 11 can be subsumed with the keywords "Tessellation”, "Multi Threading Support” and "Compute Shader”. The hardware based Tessellation is an old friend, since both AMD/Ati and Nvidia have been working on it with some former graphics cards. Now Tessellation is a feature of DirectX 11. Thereby objects are disassembled into several vertexes.
The Multi Threading Support will be noticeably improved with DirectX 11, especially the section of resource management. Therefore CPUs are more efficient in preparatory works for the GPU.
Compute Shader is about using the calculating power of the GPU, independent of the traditional render pipeline, for common tasks. Nvidia and AMD are doing this already, but with their own APIs only.
Microsoft talks about DirectX 11 being compatible to DirectX 10. So they don't want to make the same mistake as with the transition from DirectX 9 to DX 10, where we had a clear differentiation between the appropriate graphics cards.
It is yet unclear, which way DirectX 11 will be distributed by. A stand-alone version would be possible but making a bundle with a new Service Pack for Vista would be another way, too.
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