Vite + TypeScript + three.js + Rapier raycast vehicle, fixed 60 Hz step.
Flat plate, seeded obstacle scatter, chase camera, debug HUD. Car condition
(engine/tires/chassis) degrades permanently and is derived into handling
numbers, so decline is felt through the wheel rather than read off a meter.
src/sim/ is kept free of three.js and Rapier imports — the later heat, region
and front-line systems all live there, and staying engine-free is what makes
them unit-testable without a browser.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
