A function to run before an edge of the given type is relocated from its current source or target to a new source or target. Returning false from this method will abort the move.
Candidate source. May be the edge's current source, or may be a new source.
Candidate target. May be the edge's current target, or may be a new target.
The edge that is being moved.
A function to run before an edge of the given type is relocated from its current source or target to a new source or target. Returning false from this method will abort the move.