Sand Art

Sand Art is a falling-sand toy: a glass case full of tiny square grains, each one working out where to go sixty times a second. Sand pours and piles at a proper angle of repose. Water runs downhill and settles flat. Oil floats on the water and catches light from a passing spark. Fire climbs, burns out and leaves smoke. Steam rises to the roof, cools and rains back down. Plants drink from the waterline and creep upward, seeds sprout where they land wet, salt dissolves into brine that sinks, ice creeps across a still pond, and lava sets hard into stone the moment it touches water. Twenty materials in all, each with its own grainy colours, drawn as crisp chunky pixels.

The tray along the bottom holds a jar of every material, with a live count of how much of it is in the box. Choose a brush from one to twenty-four pixels wide, then paint freehand, drag a straight line or fill a rectangle. Drop in a spout and it pours the chosen material forever; drop in a drain and it swallows whatever touches it. Pause to arrange something exactly, step one frame at a time to watch a reaction up close, or turn gravity a quarter turn and let the whole box fall sideways.

Eight scenes are built in to get you started: a waterfall over stone shelves, a forest fire beside a pond, a volcano pouring lava into the sea, an hourglass, a tank of oil and water, a garden under a dripping tap, an ice cave and a maze for the sand to find its way through. Save your own scenes to your browser and open them again later, and take a snapshot as a PNG whenever the box looks right. It runs on a phone, a tablet or a desktop: one finger paints, two fingers held still stop the world, and the keyboard picks materials with the number keys.