A browser-based 3D game engine built from scratch in TypeScript, Three.js, and Rapier physics — designed around a modular animation pack system that makes characters composable. Instead of shipping a single game, Gradian is a platform: characters, animation libraries, combat mechanics, and physics systems that can all be swapped, tuned, and extended at runtime.
The engine features a body-split animation system that blends upper and lower body independently — allowing mouse-aimed combat to combine with any movement animation without drift or rotation artifacts. Animations are sourced from Mixamo FBX files, processed through a custom bake pipeline that strips root motion, compensates for hips rotation, and bakes quaternion keyframes per bone.