Clustered Pre-convolved Radiance Caching

Hauke Rehfeld, Tobias Zirr and Carsten Dachsbacher

Eurographics Symposium on Parallel Graphics and Visualization 2014



    , author = {Hauke Rehfeld and Tobias Zirr and Carsten Dachsbacher}
    , title = {Clustered Pre-convolved Radiance Caching}
    , booktitle = {Eurographics Symposium on Parallel Graphics and Visualization}
    , series = {EGPGV14}
    , year = {2014}
    , publisher = {Eurographics Association}


We present a scalable method for rendering indirect illumination in diffuse and glossy scenes. Our method builds on pre-convolved radiance caching (RC), which enables reusing the incident radiance computed at a surface point for its neighborhood. Our contributions include efficient and robust generation of these RCs based on a pre-filtered voxel representation that stores scene-geometry and surface illumination. In addition, we describe a distribution strategy that places the RCs according to screen-space clusters to ensure all pixels have valid radiance data when evaluating indirect illumination. The results demonstrate the scalability of our method and analyze the relation between render quality, surface glossiness and computation time, which depends on the number of caches and their resolution.