Won’t work for physics.
Remeber the whole point above was that the OP/or just a user wanted the disk to move smoothly with physics.
@jwatte
I think its overkill, which is why I have never seen it on any non-custom engine.
But the fact there are a few custom engine that have it should mean there are some user cases for it.
The point of cost however is that you can branch the checks I listed and get a possibly faster result (since its not involving pi on at least one front).
If you want to visually represent that solution as a Tourus you can - but creating visual colliders in engine is more problematic/expensivd than just doing the math. By a lot…
Even with simple drawdebugsphere which we all surely used billions of times…
Physx wheeles used simple discs - but it was only visible by issuing console commands to display the physx colliders.
PXVIS COLLISION