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c++vectorquaternionscoordinate-systems

Quaternion from 6 vectors (rotating one coordinate system into another)

I have 6 unit vectors (representing the X/Y/Z axis) of 2 arbitrary coordinate systems. The vector values of the second coordinate system are based on the first system. I need to rotate one system into the other and return the matching quaternion. What would be the most reasonable way to do this in c++?

There are a number of posts on SO talking about converting y-up/z-up/left-/right-handed systems into each other, unfortunately I need this to be a generic solution for any 6 unit vectors. Thanks for any insights.

Solution

  • 3 orthogonal vectors it is probably rotation matrix 3x3. You can build 2 matrices and find relative rotation as r_relative = r1.transpose() * r2;

    Than convert matrix to quaternion using any tested lib.

    Or convert both rotations to quaternion and

    q_relative = q1.inverted() * q2;