Ice Crystal Formation: Diffusion-Limited Hexagonal Growth (2D)
2D snow-crystal lab: a Reiter-style cellular automaton on a hexagonal lattice grows a frozen dendrite from diffusing water vapor, with live ambient density, attachment rate and diffusion-speed controls so you can watch plates, dendrites and needles emerge from the same three numbers.
This 2D companion replaces the 3D version's scripted branch-and-mirror geometry with a real Reiter-style cellular automaton: thousands of independent hexagonal cells each carry a diffusing water-vapor mass, gain mass when touching ice, freeze once that mass crosses a threshold, and get refilled at the domain edge to simulate an infinite ambient supply — the crystal's hexagonal symmetry emerges entirely from the lattice and the uniform local rules rather than being hard-coded, and the same three sliders that drive real snow-crystal morphology diagrams (ambient density, attachment rate, diffusion rate) let you steer growth between solid plates, branching dendrites and thin needles.
Hexagonal-lattice cellular automaton for diffusion-limited ice-crystal growth: vapor mass diffuses between unfrozen cells, boundary cells accumulate an attachment bonus, cells freeze past a mass threshold, and the domain edge is refilled toward an ambient density — six-fold symmetry emerges from the lattice geometry itself.
2D · HTML5 Canvas 2D · 60 FPS target · runs fully client-side, no install