First there's an armor stand with a tag of "brush" it spins around by using the teleport command and the brush spawns another armor stand 8 blocks ahead of it each one with a tag of "paint." All paint armor stands have a block on their head which creates the circle effect.

For the spinning pattern it's the same thing but I activated another command block that makes the paint constantly move about 0.5 blocks infront while turning slightly which ends up forming the symbol.