public static void RotFromTo2Quat(Matrix x, Matrix y, Matrix q)
{
Matrix axis = new Matrix(3, 1);
axis.Cross(y, x);
axis.Normalize();
double angle = Math.Acos(x.Dot(y));
double s = Math.Sin(angle / 2.0);
q[0] = axis[0] * s;
q[1] = axis[1] * s;
q[2] = axis[2] * s;
q[3] = Math.Cos(angle / 2.0);
}
public static void RotFromTo2Quat(Matrix x, Matrix y, Matrix q)
{
Matrix axis = new Matrix(3,1);
axis.Cross(y, x);
axis.Normalize();
double angle = Math.Acos(x.Dot(y));
double s = Math.Sin(angle/2.0);
q[0] = axis[0]*s;
q[1] = axis[1]*s;
q[2] = axis[2]*s;
q[3] = Math.Cos(angle/2.0);
}