* The exact contents depend on the API - on D3D11 this is the bytecode
blob, on Vulkan it's the SPIR-V. On OpenGL it is just a concatenation
of all the source files passed in sequence.
* The transform feedback is placed on the geometry shader tab the same as
in D3D11. It doesn't merit its own whole tab and that seemed like the
best place to put it (last processing stage before rasterization).
* To aid understanding, further stages are marked disabled if rasterizer
discard is on, and if no geometry shader is bound the stage is renamed.
baldurk