Kenneth Graunke writes:
> Implementing the GetTransformFeedbackVertexCount() driver hook allows
> the VBO module to call us with the right number of vertices.
>
> The hardware doesn't directly count the number of vertices written by
> SOL, so we instead use the SO_NUM_PRIMS_WRITTEN(n) counters an
Implementing the GetTransformFeedbackVertexCount() driver hook allows
the VBO module to call us with the right number of vertices.
The hardware doesn't directly count the number of vertices written by
SOL, so we instead use the SO_NUM_PRIMS_WRITTEN(n) counters and multiply
by the number of vertice
