One beam of a lattice: its two end points and its thickness at each.
The unit vector pointing from the start vertex to the end vertex.
The vertex the beam ends at.
The number of beams sharing the end vertex.
The beam's radius at its end (half its thickness).
Straight-line distance from start to end.
The beam's center line as a Line.
This beam in a Beam List of one.
The vertex the beam starts at.
The number of beams sharing the start vertex.
The beam's radius at its start (half its thickness).
Items that are each a Beam. One Beam wired where a list is taken counts as a list of one.