Yep. For the radiosity based global illumination things, it's the most common way of framing and solving the way light energy is passed through an environment. And most of the work is in minimizing the computationally expensive visibility operations (shadows, etc) by determining how much light energy is going to pass between two surfaces (based on distance, size, orientation, visibility, etc), and then computing using the fewest rays and the right level of resolution of the energy to efficiently utilize compute resources. Basically... :)
I'm currently working on a cute little rasterizer in JS; a software radiosity engine would be really fun! Would you mind shooting me an email (link in profile) with any links/resources you think might be helpful for a noob?
https://graphics.stanford.edu/papers/texture/texture.nocolor...