quaternion

name	quaternion
description	Rotation math in the AMC web repo — track waypoint rotations are {x,y,z,w} quaternions handled with the quaternion package in TrackEditor utils. Read before touching track rotation or 3D-orientation code.

quaternion

• Track data stores waypoint rotations as {x, y, z, w} quaternions (validated by quaternionSchema in src/lib/schema/track.ts).
• Rotation math uses the quaternion npm package inside src/lib/components/TrackEditor/utils/ (e.g. autoRotate.ts, normalized.ts); vector helpers live in src/lib/utils/math/.
• Don't convert to Euler angles for intermediate math — work in quaternions and follow the existing utils, which have colocated tests.

Related: [[codebase-patterns]], [[zod]]