Microsoft Details Shader Model 6.0
 

Microsoft is giving final touches to Shader Model 6.0, an update to a key component of its Direct3D API. This succeeds Shader Model 5.0, which remained largely unchanged since the introduction of DirectX 11.0 in 2009. Shader Model 6.0 provides a more optimized pathway for shader code to make its way to the metal (GPU, hardware). The outgoing Shader Model 5.0, which is featured on DirectX 11 and DirectX 12, relies on FXC, an offline shader compiler, to both compile and optimize HLSL shader code, supporting HLSL v1.4 to v5.1 code.

Shader Model 6.0, on the other hand, dedicates compiling to Clang HLSL compiler, and optimization to multiple LLVM passes. Since Shader Model 6.0 supports HLSL code from v5.0 upwards, it should also benefit existing DirectX 11 and DirectX 12 apps, while relegating older apps to the then legacy Shader Model 5.0 pathway. In addition, Shader Model 6.0 claims to provide the right performance to cope with API level features such as tiled resources (mega-textures). It remains to be seen how Microsoft deploys Shader Model 6.0.

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