ketyl_corona

The light a ketyl throws off itself — the shell around the body, the aura beyond it, the afterimages the trail is made of, and the half-circle a discharge throws forward.

One property, glow, picks between two readings of the same sphere. At 0 it is a RIM: brightest at the silhouette, so the shell has an edge you can see, which is what the radical's own skin should look like. At 1 it is a GLOW: brightest where you look straight through the middle and exactly zero at the silhouette, so it has no edge at all, which is the only way a large aura is not a visible bubble.

The shell draws both faces, so the reading is taken off the magnitude of the view cosine. Taking the signed one paints the entire far hemisphere at full rim and the shell comes out a flat white disc.

Wetness beads on it before it puts it out: a film of water breaks a glow into blotches, and that is the first thing that happens to a ketyl meeting water.

State comes off per-instance lane 0, (charge, wetness, flare, fade); an all-zero lane falls back to (1, 0, 0, 1).