Model alignment to world coordinate system

Thank you very much for your prompt response.

  1. I apologize for not being clear earlier. I cannot manually align my models as it isn’t accurate enough for my needs.

  2. I don’t mind whether it’s done with or without a GUI. I’m currently learning Python, so it would be great to use it for this task and enhance my skills.

You can see exactly what I want to achieve in the first image:

  1. First, set the red point as the origin of the world coordinates (0,0,0).
  2. Then, set the green line as the Z-axis of the world coordinates.

The second image shows exactly what I want, but it’s done using another software (Geomagic Wrap). I would prefer to use only open-source software for my study, but it should give you an idea.

You can see two circles; I want to achieve that in Slicer too. I think I can manage that on my own, but if I can’t, I’ll discuss it in another post… haha.

I hope I was clear enough. Thanks a lot in advance for your help!