Bloom

drop ink twice. the wet half decides.

drag ink across a damp edge and watch one stroke do two things

Watercolour has one rule: pigment goes where the water goes, and stays where the water leaves. The same stroke feathers out on wet paper but soaks straight in on dry paper, where the edge locks where you stopped.

Concepts: fluid-flow, color.

An interactive you play with one thumb, on Wundr.