//http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToAngle/
public MyQuaternion ConverFromAxisAngle(MyQuaternion _A)
{
MyQuaternion Result = _A;
if (Result.W > 1)
{
_A.Normalize(Result);
}
float angle = 2 * Mathf.Acos(Result.W);
float s = Mathf.Acos(1 - Result.W * Result.W);
if (s < 0.01f)
{
Result.X = _A.X;
Result.Y = _A.Y;
Result.Z = _A.Z;
}
else
{
Result.X = _A.X / s;
Result.Y = _A.Y / s;
Result.Z = _A.Z / s;
}
return(Result);
}
//http://www.euclideanspace.com/maths/geometry/rotations/conversions/angleToQuaternion/index.htm
public MyQuaternion ConvertToAxisAngle(MyQuaternion _A, float _ALFA)
{
MyQuaternion Result = _A;
Result.W = Mathf.Cos(_ALFA / 2);//definicion del angulo teta
Result.X = Result.X * Mathf.Sin(_ALFA / 2);
Result.Y = Result.Y * Mathf.Sin(_ALFA / 2);
Result.Z = Result.Z * Mathf.Sin(_ALFA / 2);
Result.Normalize(Result);
return(Result);
}