Snowflake Dendritic Growth — 3D Ice Crystal Habit Simulator

A real snow crystal's shape is decided molecule by molecule, as water vapor diffuses onto a growing hexagonal ice lattice under conditions that shift constantly as the crystal falls through the atmosphere. This simulator runs a diffusion-limited cellular automaton on a hexagonal grid — the same class of model researchers use to reproduce the instability that turns a flat ice face into a branching dendrite — and renders every frozen cell as a hexagonal prism whose height-to-width ratio follows the real Nakaya diagram, so temperature and supersaturation visibly steer the crystal between plates, columns, needles and stellar dendrites in real time.