code: public Vector3d normalize(Vector3d dest) {
          double invLength = 1.0 / length();
          dest.x = x * invLength;
          dest.y = y * invLength;
          dest.z = z * invLength;
          return dest;
      }
docs: /* (non-Javadoc)
  @see org.joml.Vector3dc#normalize(org.joml.Vector3d)