What am I looking at?
Each cat is a closed outline expressed as a Fourier series. Every rotating arm adds a circular motion; their sum places the tracing tip. The largest motions come first, then smaller ones supply the details. Each cat has its own tip, pace, and orientation, so their complete outlines overlap and deform together as the cats reveal themselves.
The detail slider sets the number of terms per cat. Every cat begins as a complete circle. After a short pause, automatic detail smoothly adds terms, reshaping the whole outline rather than tracing it into existence. Turn off the circles for just the emerging outlines. The seed in the URL recreates the same scene.