Extras

anthemion-khysis

Pigment spilling into a wet ground

Built for the shelf’s one test, and built carefully because its state machine is achlys’s: a pointer stroke written into a ping-ponged buffer that decays back. What differs is the direction and the physics — that one clears fog to reveal a scene, this one lays pigment onto an empty ground, and mist re-condenses uniformly where paint does nothing uniformly. It is also the shelf’s first light component: seven dark fields and a primed canvas.

A wash of three dyes diffusing through a woven canvas, one five-point step a frame. The weave is not a texture laid over the picture — it is the diffusivity field, so the raised tooth resists and the valleys conduct, and a wash strings along the threads and breaks its own edge on the cloth. Marks do not dim on a timer: a fixed amount of pigment over four times the area is a quarter as strong, which is why two spills that touch genuinely merge and why the edge goes ragged. Water leaves the middle of a wash before the rim and carries pigment outward with it, which is the dark ring on every watercolour, and it is gathered rather than drawn. Colour is Beer-Lambert over the three dyes, so it mixes subtractively — blue over yellow comes out green and two washes crossing are darker than either. Set gate to pointer and the pointer spills as it approaches. Without WebGL it is the primed ground with two faint washes, and the gradient is on the element itself so it survives having no JavaScript at all.