d3def53be5
If a mesh is known to be manifold, then it's not necessary to increment the stencil buffer 2 times anymore. But we still need to account properly for degenerate triangles. In this case, only generate a quad if the tri is facing the lamp. If there is a degenerate loop, the other edge will either cancel the increment (if it is also facing the light) or not produce a quad (if not facing). This will always give the correct count.