D3D11 in Metro doesn't support D3DReflect? (Why Not?)

Question

D3D11 in Metro doesn't support D3DReflect.

Why not?

My API uses this to dynamically get the constant buffer sizes of shaders. Is there any other way to get a constant buffer size dynamically in D3D11 without a ID3D11ShaderReflection object? Or get the constant variables by name?

• What if I wanted to make a shader compiler tool for Metro?

• What is I wanted to make an Art application that allowed you to dynamically generate complex brushes that requires shader generation. But this doesn't work.

Does Windows(Desktop), OSX, Linux, iOS or Android have these shader limitations?

No, so why on earth does Metro?

Answer 1

See http://social.msdn.microsoft.com/Forums/en-US/wingameswithdirectx/thread/9ae33f2c-791a-4a5f-b562-8700a4ab1926 for some discussion about it.

There is not an official position explaining why they made such restriction, but it is very similar to the whole restriction of dynamic code execution on WinRT. So your application scenario is unfortunately not possible.

Though, It would be feasible to hack/patch d3dcompiler_xx.dll and redirect all dll imports to call another DLL that would use authorized only APIs, but that's quite some work, and It is not even sure that this is legal (even by extracting the dll code from original d3dcompiler and rebuilding a new dll).

Another option for your scenario is to send the shader over the internet to a server that compiles and returns bytecode and reflection info... far from being perfect.

Among the platforms you mention, probably iOS is the one that could have the same restriction (I don't develop on this platform, so I can't confirm it).