/// <summary>
///
/// </summary>
/// <returns></returns>
public virtual bool IsInteriorsConnected()
{
// node the edges, in case holes touch the shell
IList splitEdges = new ArrayList();
geomGraph.ComputeSplitEdges(splitEdges);
// form the edges into rings
PlanarGraph graph = new PlanarGraph(new OverlayNodeFactory());
graph.AddEdges(splitEdges);
SetInteriorEdgesInResult(graph);
graph.LinkResultDirectedEdges();
IList edgeRings = BuildEdgeRings(graph.EdgeEnds);
/*
* Mark all the edges for the edgeRings corresponding to the shells
* of the input polygons. Note only ONE ring gets marked for each shell.
*/
VisitShellInteriors(geomGraph.Geometry, graph);
/*
* If there are any unvisited shell edges
* (i.e. a ring which is not a hole and which has the interior
* of the parent area on the RHS)
* this means that one or more holes must have split the interior of the
* polygon into at least two pieces. The polygon is thus invalid.
*/
return(!HasUnvisitedShellEdge(edgeRings));
}
/**
* Use a GeometryGraph to node the created edges,
* and create split edges between the nodes
*/
private ArrayList NodeEdges(ArrayList edges)
{
// intersect edges again to ensure they are noded correctly
GeometryGraph graph = new GeometryGraph(0, _geomFact.PrecisionModel, 0);
//for (Iterator i = edges.iterator(); i.hasNext(); )
foreach (object obj in edges)
{
Edge e = (Edge)obj;
graph.AddEdge(e);
}
SegmentIntersector si = graph.ComputeSelfNodes(_li);
/*
* if (si.hasProperIntersection())
* Debug.println("proper intersection found");
* else
* Debug.println("no proper intersection found");
*/
ArrayList newEdges = new ArrayList();
graph.ComputeSplitEdges(newEdges);
return(newEdges);
}
