For sure that's a big reason but it's also a useful basis for doing lighting cal...

djmips 3 months ago | parent | context | favorite | on: Introduction to spherical harmonics for graphics p...

For sure that's a big reason but it's also a useful basis for doing lighting calculations because of their sphere like nature. They are quite efficient in dynamic scenes and historically used in a lot of precalc to do something akin to real time Global Illumination