Create a Three.js app that shows a diamond with correct light calculations.
> correct light calculations
What are you expecting? Ray tracing?
Not necessarily. It could start by using diamond's IOR, and use that to dictate a common brdf calculation. Along with some approximate refraction, perhaps using a equirectangular projected sphere map or something for the background.
I love this. So brutal, but also so cool to know one day that will be easy for the models.