Tangent plane to a centerline

[bserrano (Belen Serrano Antón)]

@lassoan

The views are always orthogonal and longitudinal (tangential), the additional sliders are just for specifying the additional degrees of freedoms for rotations (orientation of the view up vector in slice view and rotation of the curve normal vector).

Hi,

I’ve been working with planes that are perpendicular and tangential (longitudinal) to a centerline in Slicer.

I understand that the views are always orthogonal and tangential to the centerline, and that additional sliders control degrees of freedom like the rotation of the curve’s normal vector.

My question is: How does Slicer determine the orientation of the tangential plane when the rotation angle is set to 0°?

Specifically, how does it know how to align the up vector or normal to separate, for example, a vessel into superior and inferior zones in a consistent way? (see figure)

Thanks in advance!