A phyllotaxis-style spiral with brightness banding driven by r mod t. After ひさだん (hisadan), CC BY-SA 2.0 — original code at https://scrapbox.io/hisadan/ , shared by Cliff Pickover (@pickover) on 2024-05-05. Math: for r in 0..TAU*90 step 0.23, fill(r%t), circle(r*sin(r)+400, r*cos(r)+400, sqrt(r)); t advances each frame.