Developer builds deterministic 30fps capture tool for a sub-30fps game renderer

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A developer working on a side project needed to capture smooth in-game footage without reconstructing scenes in a video editor. The standard approach of using Playwright screenshots failed because automation slowed rendering too much, causing timing drift and stuttering. To fix this, they replaced the browser's requestAnimationFrame with a virtual queue and exposed a step function that advances simulation time by exactly 1/30th of a second per captured frame, decoupling footage smoothness from actual render speed. The result is deterministic 30fps video where every run with the same seed produces an identical clip, regardless of how long each frame takes to draw. The game is built with Three.js, Rapier physics, React for the HUD, and TypeScript, packaged via Tauri.

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