Spherical harmonic (SH) lighting models require efficient and general libraries for evaluation of SH functions and of Wigner matrices for rotation. We introduce an efficient algebraic recurrence for evaluation of SH functions, and also implement SH rotation via Wigner matrices constructed for the real SH basis by a recurrence. Using these algorithms, we provide a freely distributable C / OpenGL implementation for SH diffuse unshadowed, shadowed and inter-reflected models. Our implementation allows flexible switching of scene, light probe, SH degree and lighting model at run time.
|Title of host publication||GRAPHITE 2007: Proceedings of the 5th International Conference on Computer Graphics and Interactive Techniques in Australia and Southeast Asia|
|Place of Publication||New York|
|Publisher||Association for Computing Machinery (ACM)|
|Number of pages||4|
|Publication status||Published - 2007|
|Event||GRAPHITE 2007 - Perth, Australia|
Duration: 1 Dec 2007 → 4 Dec 2007
|Period||1/12/07 → 4/12/07|
Lisle, I., & Huang, T. (2007). Algorithms for Spherical Harmonic Lighting. In S. Spencer (Ed.), GRAPHITE 2007: Proceedings of the 5th International Conference on Computer Graphics and Interactive Techniques in Australia and Southeast Asia (pp. 235-238). New York: Association for Computing Machinery (ACM).