Calculate angle between oriented bounding boxes

Development
1

Operating system : Win10 x64:
Slicer version : 4.11.20200930

I’m a medical doctor and fairly new to the slicer 3d application, I am trying to calculate the angles between oriented bounding boxes created with the python code here Documentation/Nightly/ScriptRepository - Slicer Wiki

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I tried to use the segment statistics module for this task but cannot fully understand how to use the data provided. What i need is a simple solution like the angle planes module since i’ll be dealing with huge amount of calculations. Thanks for your patience…

2

obb_direction_ras_x, obb_direction_ras_y, and obb_direction_ras_z are vectors specifying direction of coordinate system axes. You can get angles between vectors using standard vector math, but you can also use convenience functions in VTK, for example:

v1 = box1_obb_direction_ras_x
v2 = box2_obb_direction_ras_x
box1_box2_x_angle = vtk.vtkMath.DegreesFromRadians(vtk.vtkMath.AngleBetweenVectors(v1, v2))
1 Like
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Thank you for quick reply. I have managed to measure the vector angles as you described but was unable to produce accurate reproducible results. I need to measure a specific angle for each OBB like this one

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Actually it’s the angle between the central planes of each OBB
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would you please point me to the right direction?. Thanks in advance…