A wildfire's material-state nodes (see Wildfire.node).
Share 0…1 of white ash vs black char (heavy fuel burnt right through; the ash input).
ash
Burn scar 0…1 (the burn state).
burn
Ground glow 0…1: a band at the flaming front, sparse spots in the smouldering interior (the heat input).
heat
A wildfire's material-state nodes (see Wildfire.node).