Efficient GPU rendering of subdivision surfaces using adaptive quadtrees

Abstract

We present a novel method for real-time rendering of subdivision surfaces whose goal is to make subdivision faces as easy to render as triangles, points, or lines. Our approach uses standard GPU tessellation hardware and processes each face of a base mesh independently, thus allowing an entire model to be rendered in a single pass. The key idea of our method is to subdivide the u, v domain of each face ahead of time, generating a quadtree structure, and then submit one tessellated primitive per input face. By traversing the quadtree for each post-tessellation vertex, we are able to accurately and efficiently evaluate the limit surface. Our method yields a more uniform tessellation of the surface, and faster rendering, as fewer primitives are submitted. We evaluate our method on a variety of assets, and realize performance that can be three times faster than state-of-the-art approaches. In addition, our streaming formulation makes it easier to integrate subdivision surfaces into applications and shader code written for polygonal models. We illustrate integration of our technique into a full-featured video game engine.