Here are some pictures with reflection and glass spheres. The shadows are somewhat conspicuously missing: this is because the shadows and reflection refuse to play nice together. When I use them both, spots (like if I don’t use a large enough epsilon, but that appear with any epsilon) appear all over the spheres. If anyone has run into this and fixed it, please e-mail me (its konieczn@cs.utah.edu).

 

Reflective and see-through sphere in the middle

 

Same, but with a tinted blue sphere

 

 

 

 

 

The same blue sphere, but with reflection only

Multi-reflections with all the spheres (and with dimmer lights, and green light)