Autumn — falling leaves simulation
A central maple drops leaves across an autumn scene. Cursor pushes leaves around; click sends a gust through the canopy.
How it works
One large central maple. Recursive branches to depth 7 with side sprouts; canopy mass = ring of sugar-maple sprites at every branch tip.
Sky + ground + tree pre-rendered to an offscreen canvas at init/resize and blitted each frame; only falling leaves cost per frame. Leaves use per-color baked sprites (drawImage, not retraced paths).
Count = clamp(W·H/4000, 280, 560). Cursor pushes leaves; click gusts a burst.