Today we’ll be talking about the presentation given by Peter Shirley from Activision at High Performance Graphics 2025. In it, he discussed the use of exponential Spherical Harmonics to replace the Split-Sum method, by re-encoding the environment map with a view-dependent factorization. This approach removes the need for a multi-level cube map, saving disk space and making the process noticeably faster — though, with some limitations

Watch full presentation:

https://www.youtube.com/watch?v=jN7FX5COASM