Clayton Shonkwiler made [url=http://flotsam.sellingwaves.com/post/142103728586/reinvention-source-code]a nifty gif[/url] with rotating hexagonal spokes. That got me playing around with generalizing. The most interesting math was probably the trig to figure out a good place to put the outer ring. The color change was trying out Daniel Ruiz Aguilera's [url=https://twitter.com/druizaguilera/status/716237305179148288]tip for the dynamic HSV[/url] in GeoGebra.