This is something that I missed from the initial implementation of large FVF. In large FVF the transform is sent per vertex in an attribute, and the vertex position is the original vertex position. This is so that the original vertex position can be read and modified in a custom shader.
This whole system is therefore incompatible with the legacy hardware transform method, whereby the transform is sent in a uniform. The shader already correctly ignores the uniform transform, but there are some parts of the CPU side logic that can be confused treating large FVF batches as if they were hardware transform.
This PR completes the logic by making the CPU treat large FVF as though it was software transform.
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