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**Basic question on quaternions**

*(by mantielero)*

I am not that familiar with quaternions (I understand the basics). I know that they are used typically with rotations.

I have some questions:

1. It is not clear to me how they are used to defined normals. Could you explain a little bit about this topic?

2. If I use `Slvs_MakeQuaternion` with (1,0,0), (0,1,0). I understand that I get a non rotated basis coordinate system. The quaternion will be (1,0,0,0). Is this correct?

3. Secondly, if use `Slvs_QuaternionU`, `Slvs_QuaternionV`, `Slvs_QuaternionN`, I get the new basis coordinate system. The basis for quaternion (1,0,0,0), will be: u=(1,0,0), v=(0,1,0), n=(0,0,1). So the normal will be (0,0,1). Is this correct?

Thanks a lot,

José María

I have some questions:

1. It is not clear to me how they are used to defined normals. Could you explain a little bit about this topic?

2. If I use `Slvs_MakeQuaternion` with (1,0,0), (0,1,0). I understand that I get a non rotated basis coordinate system. The quaternion will be (1,0,0,0). Is this correct?

3. Secondly, if use `Slvs_QuaternionU`, `Slvs_QuaternionV`, `Slvs_QuaternionN`, I get the new basis coordinate system. The basis for quaternion (1,0,0,0), will be: u=(1,0,0), v=(0,1,0), n=(0,0,1). So the normal will be (0,0,1). Is this correct?

Thanks a lot,

José María

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