Even with the advent of hardware-accelerated ray tracing in modern GPUs, only a small number of rays can be traced at each pixel in real-time applications. This presents a significant challenge for path tracing, even when ...

We show that Catmull-Clark subdivision induces an invariant one-to-four refinement rule for halfedges that reduces to simple algebraic expressions. This has two important consequences. First, it allows to refine the halfedges ...