Real-Time Level-of-Detail rendering with ReSTIR

摘要

Rendering complex scenes in real time remains challenging due to strict performance constraints. Geometric level of detail (LoD) is widely used to reduce cost by replacing high-frequency geometry with prefiltered representations. ReSTIR significantly improves real-time rendering quality by reusing samples across space and time; however, its effectiveness degrades in the presence of complex geometry, where high-frequency detail reduces reuse efficiency. Moreover, prior ReSTIR methods require the same mesh topology across frames, causing sample reuse to break when switching LoD. In this paper, we introduce a surface point mapping that enables sample reuse across frames containing meshes with different topologies. Building on our method, we enable LoD-aware ReSTIR by maintaining valid spatiotemporal reuse under geometry LoD changes. Our approach restores reuse efficiency in LoD scenes and significantly improves rendering quality compared to prior ReSTIR methods.