It's not much but it's honest work. Done for now. Looks good enough to me. Get it on github or don't. https://github.com/kovrom/circle

Also looks fine on a regular not round screen https://blossom.primal.net/1a8e746c8878bb0b3ad900d9ac3658844872b0333affeda9cb8bcdcedbf26a67.mp4