Tambour

Built to one reference and fitted to it. The ribs were traced off it row by row, and each is its own position plus two waves, so they wander the way rolled glass does. Each flute bends the light a little sideways, dims it in the groove it starts from and brightens it toward the next rib, and every rib's edge catches the light as a thin line: cyan on the left, red on the right, still glowing where the light itself has faded.

The light is ten soft lobes that add up and go through one exposure curve, so the red burns through to pink-white at its core while the cyan keeps its colour, and the faintest light is crushed to true black so the bar has an edge.

The glass holds still and your cursor moves the light behind it: the bar slides toward the cursor, and the ribs along its path light up as it passes. Left alone it drifts very slowly. With reduced motion you get the still frame, which is the reference.

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