Falling Sand

Pour sand, water, oil, fire, lava and acid, and watch them react.

0/3challenges

Brush sizecells

Speedsteps per frame

Sand: 0
Water: 0
Burning: 0
Plant: 0
Glass: 0

The model

A cellular automaton, the same family as the Game of Life, but with physics-flavoured rules. Every cell holds one material. Each frame, from the bottom row up, sand falls and slides off piles, liquids fall then spread sideways, and gases rise and fade.

Heavier things sink through lighter ones, so sand drops through water and oil floats on it. Fire spreads to wood, oil and plants and is put out by water, which turns to steam. Lava sets water to steam and itself to stone, and slowly fuses sand into glass. Acid eats almost anything.

Try this

Pour oil on water, then drop one spark of fire. Grow a plant by dripping water onto a single plant cell. Pour lava into a pool and watch obsidian form.

Rules, not equations: densities and burn rates are tuned to look right, not measured. Educational model, not an engineering design or validation tool.

Achievements0/3

Glassblower +30Make 50 cells of glass from sand and lava.
Greenhouse +30Grow 1,500 cells of plant.
Controlled burn +20Let a big fire burn itself out.

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