/// <summary>
/// 旋转轴和旋转角(单位四元数有效)
/// </summary>
/// <param name="angle"></param>
/// <param name="axisNormal"></param>
public void ToAngleAxis(out float angle, out Vector3 axisNormal)
{
Vector3 axis = new Vector3(
MathS.Abs(x) <= Threshold ? 0f : x,
MathS.Abs(y) <= Threshold ? 0f : y,
MathS.Abs(z) <= Threshold ? 0f : z
);
if (axis == Vector3.zero)
{
angle = 0;
axisNormal = Vector3.zero;
}
else
{
float length = axis.magnitude;
angle = MathS.Atan2(length, w) * 2 * MathS.RadToDeg;
axisNormal = axis / length;
}
}
/// <summary>
/// 欧拉角(单位四元数有效)
/// </summary>
/// <returns></returns>
public Vector3 ToEulers()
{
Vector3 euler = Vector3.zero;
Matrix m = ToMatrix();
if (MathS.Abs(m[1, 0]) <= Threshold &&
MathS.Abs(m[1, 1]) <= Threshold)
{
euler.x = m[1, 2] <= 0 ? 90 : -90;
euler.y = 0;
euler.z = MathS.Atan2(-m[0, 1], m[0, 0]) * MathS.RadToDeg;
}
else
{
euler.x = MathS.Asin(-m[1, 2]);
euler.y = MathS.Atan2(m[0, 2], m[2, 2]);
euler.z = MathS.Atan2(m[1, 0], m[1, 1]);
euler *= MathS.RadToDeg;
}
return(euler);
}