Section by Plane
Creates a section by defining the sectioning plane. The plane is defined by three points.
1. Select Section by Plane (3 Points) from the local menu or Inspector Bar.
2. Select the object to section. You can use Shift to select more than one object, or use a selection window (first click outside the objects, then drag the window).
3. Select three points to define the sectioning plane.
4. The section is created.