[vtkusers] vnl quaternion question

[Richard Frank]

Hi,

 

I can rotation a point as below, but how to simply get back the original
point?

 

 

 

vnl_vector_fixed<float,3> pt = {0,1,0};

 

vnl_vector_fixed<float,3> axis = {0,0,1};

 

vnl_quaternion<float> q = vnl_quaternion<float>(axis,45 * M_PI / 180.0);

 

auto rotPt = q * pt * q.conjugate();

 

 

// how to invert?

 

Auto unRotPt = q.inverse() * rotPt; // doesn't seem to work

 

 

 

Thanks

 

 

Rick

 

 

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