Looks nice, I used a more complicated version during undergrad for a physics lab. It was great as you could explore length contraction, time dilation etc, and also had toggles for enabling some of the really crazy relativistic effects. https://people.physics.anu.edu.au/~cms130/RTR/

Turns out it relied on GPU acceleration at the time to work (even at low Res). https://arxiv.org/abs/physics/0701200

Might be interesting for someone to port it to a browser version