Reaction Plates — wallpaper generator

Paint mode seeds new growth under the cursor

Looks none

Each look sets the chemistry, the seed, the palette and how far to run, then grows the pattern to that point and pauses. Expect five to twenty seconds of growth, tracked by the bar at the bottom. Roll a new seed for another variation of the same look, or press Play to keep it developing.

Output

Width px

Height px

Feature scale

Pixels per cell. Higher means bolder shapes and a faster simulation; 1× is the finest detail your machine can chew through.

Reaction

kill 0.0300.075

Feed

Kill

The shaded band marks where the equations settle into a mixture that is not simply blank. Treat it as a guide rather than a fence: several of the best regimes, including spots that divide indefinitely, sit just outside it. Changing f or k does not reset the field — whatever is on screen migrates into the new regime.

Kinetics

Diffusion ratio

Timestep

Steps per frame

Seed

Density

Seed

Colour

Floor

Gamma

Export

Sharpen passes

After upscaling, the reaction runs this many steps at full resolution so the edges re-form crisply instead of looking interpolated.

Format

File name

How this works

Two chemicals in a dish

One substance is fed in from outside at a steady rate. The second converts the first into more of itself and is slowly removed. Both spread outward, but the feeder spreads about twice as fast. That imbalance is the entire trick — it turns an even mixture into spots, stripes and branching growth. Alan Turing proposed the mechanism in 1952 to explain animal markings; this is the Gray-Scott version of it.

Feed and kill

Feed sets how fast fresh material arrives, kill how fast the product is removed. Between them they decide the entire character of the pattern, and they are far more sensitive than they look. A shift of 0.001 in kill can turn a stable maze into spots that divide forever.

What the map actually tells you

The shaded region marks where an even mixture can settle into something other than blank. It is worth reading as a guide rather than a boundary: several of the most interesting regimes sit just outside it, and self-replicating spots do so precisely because there is no settled state for them to fall into, which is why they keep dividing. What the edge really predicts is fragility. Near it and beyond it a seed can just as easily fade to nothing, so if the screen goes flat, move further in.

Knowing when it is finished

Three things can happen. Some settings genuinely converge — growth fills the frame and then stops changing. Some only appear to: the pattern is complete, but defects where differently oriented domains meet anneal so slowly that they never resolve. And some never finish at all, with spots dividing and waves travelling indefinitely. The step counter under the image is the honest answer; watch whether the picture is still moving.

Longer is not better

Growth is usually more interesting than the settled state. Coral looks best while the front is still sweeping across the frame, not after it has filled every corner. Pause wherever it looks right — the same seed, chemistry and step count will reproduce that exact image again.

The edges wrap

Left meets right and top meets bottom, so patterns grow across the boundary instead of stopping at it. Every image you export tiles seamlessly.