I wish to mathematically represent point light sources inside a structure, and figure out how much like is scattered throughout the structure. Specifically, I have lighting values of a certain amount of lux, and I need to ensure that the structure has a minimum of (certain value) lux touching all surfaces (maybe excluding things like shadows under tables). I don't want to go overboard on power consumption, though. How, mathematically, should I go about figuring out how to do this? I'm thinking of simplifying the structure to something like a rectangular prism, or even just a hollow sphere of equal surface area. I'm very confused at this point and I don't really know where to start.