grainfall

A full-window interactive piece: an eroded stone cube built from 88,340 particles floats corner-up on a dark violet field with a fine film grain, turning slowly. The cursor lights the stone from where it points, a violet-to-ice-white glow on the grains with a soft bloom behind it, and pushes, swirls and drags the grains within reach: moving across the surface tears them off into sandy, glowing trails that spring back home, and resting on it opens a hole. A click scatters the whole stone in a burst from the cursor and it reassembles in a couple of seconds; dragging turns it, and it coasts with inertia back to its idle spin. The stone is generated in code from noise (chipped, rounded edges, rocky shading) and drawn with three.js and a custom point shader; the particle physics runs on the CPU. No images and no fonts. It runs at the same speed on 60 and 120 Hz screens, fits phones in portrait, and works with taps and finger drags.