pad_column

The column of melt leaving the mesa. The mesh is a lattice of degenerate quads filling the box the column occupies; each cell hashes into one piece of matter — a round droplet, or one of the stretched ribbons — and rises through the column on the film's clock, wrapping at the top, while the cylinder widens, leans and twists with altitude.

column is film.column(t) and gates the whole density, so the column arrives rather than switching on. uplight and under are how it is lit from BELOW in act three: there is no key light above it, and the piece's own emissive rim is what carries it against the starfield from 4 km in shot 13. Two materials ride this shader — a coarse one big enough to read at that range, and a fine one the camera flies through in shot 11.