Falling-Sand Playground
A falling-sand game is a cellular automaton where every pixel is a material with its own rules. Sand and salt fall and pile into slopes, water and oil flow to fill containers and float on each other by density, fire climbs through anything flammable and burns wood and plants to smoke, and steam rises and condenses back to water. Pick a material and a brush size, then click or drag to paint into the box; the grid is stepped from the bottom up so falling powders and liquids settle realistically. Walls are static so you can build funnels and dams, and everything runs locally on a canvas.
Runs 100% in your browser — simulations are computed locally on your device.
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Notes
- Each cell holds one material; the update sweeps the grid and applies simple local moves (fall, slide, displace lighter fluids), and complex behaviour like fluid levelling and fire spread emerges from those moves alone.
- Liquids are ranked by density: oil floats on water, water sinks through steam, and a denser powder falling into a lighter liquid swaps places, so sand sinks through water.
- Fire is a short-lived state that ignites flammable neighbours and decays to smoke, so a single spark can sweep through a wooden structure and then die out on its own.
- Runs 100% in your browser — simulations are computed locally on your device.
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