Circstar Math Circstar is a graph of a very simple function:
x^2*cos(delta) + y^2*sin(delta), where delta is a time variable that completes one revolution in the course of the video.

I did make one simple alteration, though. (Can't leave a good function alone, can I?) The basic function always has the same color in the center of the circle/star: the one which represents the value zero. To make the colors more interesting, I make this value cycle the color wheel over the course of the video.