Made some refinements to lighting. Originially there was only a point light without distance falloff, which is not an accurate light model in any case. The light inside the room lights the entire world, all the way to the horizon.

Cut teapot rendering time in half with some clever caching.

The final pre-defined feature of the project is done, Constructive Solid Geometry, implementing the boolean set operations union, intersection, and difference for solid geometries. This way we can use the basic geometric surface shapes to create more advanced shapes, without resorting to approximating by thousands of triangles.

Not a single feature improvement today, but instead a bit of quality of life improvements.