/// <summary>
        /// 球形插值(无限制)
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <param name="t"></param>
        /// <returns></returns>
        public static LQuaternion SlerpUnclamped(LQuaternion q1, LQuaternion q2, LFloat t)
        {
            LFloat dot = Dot(q1, q2);

            LQuaternion tmpQuat = new LQuaternion();

            if (dot < 0)
            {
                dot = -dot;
                tmpQuat.Set(-q2.x, -q2.y, -q2.z, -q2.w);
            }
            else
            {
                tmpQuat = q2;
            }


            if (dot < 1)
            {
                LFloat angle = LMath.Acos(dot);
                LFloat sinadiv, sinat, sinaomt;
                sinadiv = 1 / LMath.Sin(angle);
                sinat   = LMath.Sin(angle * t);
                sinaomt = LMath.Sin(angle * (1 - t));
                tmpQuat.Set((q1.x * sinaomt + tmpQuat.x * sinat) * sinadiv,
                            (q1.y * sinaomt + tmpQuat.y * sinat) * sinadiv,
                            (q1.z * sinaomt + tmpQuat.z * sinat) * sinadiv,
                            (q1.w * sinaomt + tmpQuat.w * sinat) * sinadiv);
                return(tmpQuat);
            }
            else
            {
                return(Lerp(q1, tmpQuat, t));
            }
        }
        /// <summary>
        /// 转换为角轴
        /// </summary>
        /// <param name="angle"></param>
        /// <param name="axis"></param>
        public void ToAngleAxis(out LFloat angle, out LVector3 axis)
        {
            angle = 2 * LMath.Acos(w);
            if (angle == 0)
            {
                axis = LVector3.right;
                return;
            }

            LFloat div = 1 / LMath.Sqrt(1 - w * w);

            axis  = new LVector3(x * div, y * div, z * div);
            angle = angle * 180 / LMath.PI;
        }
 public static LFloat AngleInt(LVector3 lhs, LVector3 rhs)
 {
     return(LMath.Acos(Dot(ref lhs, ref rhs)));
 }
 static void TestLutACos()
 {
     TestLut((i) => i * 0.001f, (p) => Mathf.Acos(p), (p) => LMath.Acos(p.ToLFloat()));
 }
        /// <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));
        }