Delegates to Quaternion.slerp, which is shortest-arc: it negates the
target's components when the dot product is negative, so an antipodal pair
travels the short way round and the result at t = 1 is -b — the same
rotation as b, with opposite components. Verified against
packages/math/src/quaternion.ts (plan D8) rather than assumed.
Quaternion adapter (§17 "quaternion", interpolation mode "spherical linear").
Delegates to
Quaternion.slerp, which is shortest-arc: it negates the target's components when the dot product is negative, so an antipodal pair travels the short way round and the result att = 1is-b— the same rotation asb, with opposite components. Verified againstpackages/math/src/quaternion.ts(plan D8) rather than assumed.