Post-Tessellation Geometry Caches

Abstract

Current 3D rendering architectures support adaptive tessellation of patches, allowing for increased geometric detail. Patches are specified independently, giving the implementation freedom to exploit parallel execution. However, this independence leads to redundant shading computations at patch corners and along edges. In this paper, we present post-tessellation geometry caches, the edge cache and corner cache, that can reduce redundant shading along patch edges and corners, respectively. We demonstrate the two caches in a software-simulated D3D11 rendering pipeline, and show that for current tessellation workloads our approach saves up to 37% of post-tessellation vertex shading using caches with as few as 8 entries.