Introduction to spherical harmonics for graphics programmers

https://gpfault.net/posts/sph.html

Article

  • Tutorial introducing spherical harmonics (SH) tailored for graphics/rendering use
  • Covers SH as basis functions for encoding lighting over a sphere
  • Real-valued Cartesian form emphasized over complex spherical-coordinate form
  • Practical focus: ambient occlusion, irradiance caching, light probes

Discussion

  • Commenters praise Cartesian form intro — easier to grasp beauty vs. complex derivation
  • SH also used in Ambisonics surround sound for arbitrary speaker decoding
  • Key appeal for graphics: compress full-sphere lighting into just 9–16 values

Discuss on HN


Type Link
Added Apr 16, 2026
Modified Apr 16, 2026