/// <summary>
        /// 夹角大小
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <returns></returns>
        public static LFloat Angle(LQuaternion a, LQuaternion b)
        {
            LFloat single = Dot(a, b);

            return(LMath.Acos(LMath.Min(LMath.Abs(single), LFloat.one)) * 2 * (180 / LMath.PI));
        }