Quaterniond.rotationTo

Set <code>this</code> quaternion to a rotation that rotates the <code>fromDir</code> vector to point along <code>toDir</code>. <p> Because there can be multiple possible rotations, this method chooses the one with the shortest arc.

@see #rotationTo(double, double, double, double, double, double)

@param fromDir the starting direction @param toDir the destination direction @return this