Same scene as before, but with implementing the Slab Test for bounding box intersections and Moller-Trumbore for triangle intersections. Also fixed most of my noise issues, and reduced bounce count to 4 because Im on a less powerful machine. Render time was 0:51:47.

1:47:02 render time with 8 bounces. This was quite involved--I found a hollow model of the teapot, spent an hour in Blender reducing triangle counts by like 95% and then cleaning it up, imported it into Unity and wrote a script to spawn 75 marbles and use the physics engine to get them to settle in appropriate positions, and then export that into a scene. Its still much noisier than I would have liked.

Glass teapot again, this time not clipping into the wall. Render time is 42:12 with 16 bounces.I wanted to put some spheres inside of the teapot, but they werent appearing for some reason.

Glass teapot. I think the reason so much of it is dark is because of a low bounce count 16. 33:54 for render.Update: Nope, there reason its dark is because it was clipping into the back wall. Whoops.

Final. 3:14 with 64 bounces. 17:48 without bounding box intersections.

Teapot without normal interpolation. 2:51 render with 64 bounces