A EdgeEndStar is an ordered list of EdgeEnds around a node. They are maintained in CCW order (starting with the positive x-axis) around the node for efficient lookup and topology building.
A list of all outgoing edges in the result, in CCW order
A map which maintains the edges in sorted order around the node NOTE: In In JSTS a JS object replaces TreeMap. Sorting is done when needed.
the coordinate for the node this star is based at.
Insert a EdgeEnd into this EdgeEndStar
Insert an EdgeEnd into the map, and clear the edgeList cache, since the list of edges has now changed
Iterator access to the ordered list of edges is optimized by copying the map collection to a list. (This assumes that once an iterator is requested, it is likely that insertion into the map is complete).