A list of the SegmentNodes present along a noded SegmentString.
Adds an intersection into the list, if it isn't already there. The input segmentIndex and dist are expected to be normalized.
the SegmentIntersection found or added.
Creates new edges for all the edges that the intersections in this list split the parent edge into. Adds the edges to the provided argument list (this is so a single list can be used to accumulate all split edges for a set of SegmentStrings).
returns an iterator of SegmentNodes