
GL spec requires user culling, then clipping then face culling. llvmpipe was doing clipping then user culling then face culling. Fix the ordering by adding a new user_cull stage that does the user culling Fixes piglit clip_cull-4.shader_test v2: simplify this a lot (Roland) Reviewed-by: Roland Scheidegger <sroland@vmware.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4560>