That is so neat. I built something a little bit like this for a simulator of a 3D portal mill. Trying it on real wood got expensive fast so for debugging runs and trials of designs I would run a simulation where the toolbit would hack out the shape out of a three dimensional array of voxels. This was then displayed using a very simple engine built with PyGame. I got a lot of use out of that and it saved days (and a small forest).

Great to see something along those lines but with much better visuals.