cinder_molten

The lava lake. A domain-warped flow field carries a skin of cooled crust plates across the surface; where the plates pull apart, the melt underneath shows through on a blackbody ramp from deep red through orange to a white-hot seam. The plates drift at a different rate from the melt, so the cracks open, close and re-knit instead of sliding as one texture.

heat (0..1) is the eruption dial: it thins the crust, speeds the flow and lifts the whole emissive ramp, so the same material reads as a sullen crater pool at t=0 and as an open furnace at t=1. Vertical faces get a separate downward-streaming read, so the slab's sides look like a magma column rather than a sheet of the top face.