Spherical Harmonics with RenderMan (some progress)
As part of my RenderMan for real-time research, I have for some time, been working on a solution for generating spherical harmonic coefficients from arbitrarily complex lighting environments for use in real-time. While not completely finished with this, I have some promising preliminary results.
First, some background. Spherical Harmonic lighting is a method for computing complex low-frequency lighting solutions in real-time by pre-calculating a series of SH coefficients which when used in a linear combination of SH basis functions, can produce an approximation of the original lighting. For more details on this process, I would direct you to Robin Green’s Spherical Harmonic Lighting: The Gritty Details. I drew much of my code from this paper.
So the other day, I got the urge to do some retro-programming. What better platform, I thought to myself, than the Nintendo Entertainment System. Unfortunately, for the beginner, programming even a very simple ROM and running it in your favorite emulator can be challenging. So here now is my small guide to getting started.