inverse method
Get the inverse quaternion rotation.
Implementation
Quaternion inverse([Quaternion? target]){
target ??= Quaternion();
conjugate(target);
final inorm2 = 1 / (x * x + y * y + z * z + w * w);
target.x *= inorm2;
target.y *= inorm2;
target.z *= inorm2;
target.w *= inorm2;
return target;
}