How we ship a rhythm-driven WebGL racer with no backend. A Web Audio decode + a Web Worker that runs FFT off the main thread, a beatmap synthesizer that turns spectral flux into a curved elevated road, an audio-clock game loop that never drifts against the music, and a Jamendo-only music source that keeps CORS out of the failure list. All from the production code of /gamecenter/sound-race.
Sound Race spawns pickups and hazards from cloned Hunyuan-generated GLB templates. Any single template can be null — because OSS was slow, or that specific asset failed to parse, or we hit a network timeout. The spawn code checks each slot and falls back to a shared procedural polytope when the GLB isn't there. Same collision box, same behavior, just a different-looking mesh. Here's the exact shape and why it's worth building even for a small feature.
Signed OSS URLs rotate every request, so the disk cache never matches. Sound Race redownloaded 13 GLBs on every visit until we sat an IndexedDB layer in front of GLTFLoader. Here's the code, why Cache Storage doesn't help, and one invalidation edge case we're leaving as tech debt.
Sound Race's 13 GLBs are compressed with Draco on upload and inflated with a WASM decoder in the browser. This post walks the whole pipeline — the @gltf-transform + draco3dgltf server side, the "if compressed is bigger, keep original" safety valve, why the decoder files live in /public/draco/gltf/ instead of on a CDN, and the exact three lines of GLTFLoader wiring that connect them.
