* For APIs where the shader namespace/bindpoint (which may be arbitrary
like 'the Nth texture resource' can be mapped, at each event, to the
actual API bind point where the object is.
* On D3D11 this is pass-through, on GL this returns the value of each
uniform.
* This also means GL shader reflection structures are properly immutable
and the variance in the uniform values is handled elsewhere.
* In future this might need to be expanded to support more complex binding
methods, where the mapping returns the resource rather than just mapping
to an integer bind ponit.
baldurk