public void findEdge(List dirEdgeList) {
    /**
     * Check all forward DirectedEdges only. This is still general, because each edge has a forward
     * DirectedEdge.
     */
    for (Iterator i = dirEdgeList.iterator(); i.hasNext(); ) {
      DirectedEdge de = (DirectedEdge) i.next();
      if (!de.isForward()) continue;
      checkForRightmostCoordinate(de);
    }

    /**
     * If the rightmost point is a node, we need to identify which of the incident edges is
     * rightmost.
     */
    Assert.isTrue(
        minIndex != 0 || minCoord.equals(minDe.getCoordinate()),
        "inconsistency in rightmost processing");
    if (minIndex == 0) {
      findRightmostEdgeAtNode();
    } else {
      findRightmostEdgeAtVertex();
    }
    /** now check that the extreme side is the R side. If not, use the sym instead. */
    orientedDe = minDe;
    int rightmostSide = getRightmostSide(minDe, minIndex);
    if (rightmostSide == Position.LEFT) {
      orientedDe = minDe.getSym();
    }
  }
 private static Geometry convertSegStrings(Iterator it) {
   GeometryFactory fact = new GeometryFactory();
   List lines = new ArrayList();
   while (it.hasNext()) {
     SegmentString ss = (SegmentString) it.next();
     LineString line = fact.createLineString(ss.getCoordinates());
     lines.add(line);
   }
   return fact.buildGeometry(lines);
 }
  private void computeNodedEdges(List bufferSegStrList, PrecisionModel precisionModel) {
    Noder noder = getNoder(precisionModel);
    noder.computeNodes(bufferSegStrList);
    Collection nodedSegStrings = noder.getNodedSubstrings();
    // DEBUGGING ONLY
    // BufferDebug.saveEdges(nodedEdges, "run" + BufferDebug.runCount + "_nodedEdges");

    for (Iterator i = nodedSegStrings.iterator(); i.hasNext(); ) {
      SegmentString segStr = (SegmentString) i.next();
      Label oldLabel = (Label) segStr.getData();
      Edge edge = new Edge(segStr.getCoordinates(), new Label(oldLabel));
      insertUniqueEdge(edge);
    }
    // saveEdges(edgeList.getEdges(), "run" + runCount + "_collapsedEdges");
  }
 private List createSubgraphs(PlanarGraph graph) {
   List subgraphList = new ArrayList();
   for (Iterator i = graph.getNodes().iterator(); i.hasNext(); ) {
     Node node = (Node) i.next();
     if (!node.isVisited()) {
       BufferSubgraph subgraph = new BufferSubgraph();
       subgraph.create(node);
       subgraphList.add(subgraph);
     }
   }
   /**
    * Sort the subgraphs in descending order of their rightmost coordinate. This ensures that when
    * the Polygons for the subgraphs are built, subgraphs for shells will have been built before
    * the subgraphs for any holes they contain.
    */
   Collections.sort(subgraphList, Collections.reverseOrder());
   return subgraphList;
 }
 /**
  * Completes the building of the input subgraphs by depth-labelling them, and adds them to the
  * PolygonBuilder. The subgraph list must be sorted in rightmost-coordinate order.
  *
  * @param subgraphList the subgraphs to build
  * @param polyBuilder the PolygonBuilder which will build the final polygons
  */
 private void buildSubgraphs(List subgraphList, PolygonBuilder polyBuilder) {
   List processedGraphs = new ArrayList();
   for (Iterator i = subgraphList.iterator(); i.hasNext(); ) {
     BufferSubgraph subgraph = (BufferSubgraph) i.next();
     Coordinate p = subgraph.getRightmostCoordinate();
     //      int outsideDepth = 0;
     //      if (polyBuilder.containsPoint(p))
     //        outsideDepth = 1;
     SubgraphDepthLocater locater = new SubgraphDepthLocater(processedGraphs);
     int outsideDepth = locater.getDepth(p);
     //      try {
     subgraph.computeDepth(outsideDepth);
     //      }
     //      catch (RuntimeException ex) {
     //        // debugging only
     //        //subgraph.saveDirEdges();
     //        throw ex;
     //      }
     subgraph.findResultEdges();
     processedGraphs.add(subgraph);
     polyBuilder.add(subgraph.getDirectedEdges(), subgraph.getNodes());
   }
 }