| gvSIG desktop 1

/*

 * Created on 12-sep-2006 by azabala

 *

 */

package com.vividsolutions.jts.geomgraph;

import java.util.ArrayList;

import java.util.Collection;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import com.iver.cit.gvsig.fmap.topology.geomgraph.SnappingEdge;

import com.iver.cit.gvsig.fmap.topology.geomgraph.SnappingNodeMap;

import com.vividsolutions.jts.algorithm.CGAlgorithms;

import com.vividsolutions.jts.algorithm.LineIntersector;

import com.vividsolutions.jts.geom.*;

import com.vividsolutions.jts.geomgraph.index.SegmentIntersector;

import com.vividsolutions.jts.geomgraph.index.SimpleMCSweepLineIntersector;

import com.vividsolutions.jts.geomgraph.index.SnapSimpleMCSweepLineIntersector;

import com.vividsolutions.jts.util.Assert;

/**

 */

public class SnappingGeometryGraph extends GeometryGraph {

        // Properties of PlanarGraph that we want to overwrite to

        // use snapping

        public static final CGAlgorithms cga = new CGAlgorithms();

        protected SnappingNodeMap nodes;

        // overwrite to catch them when returned by Snapping map

        protected Collection boundaryNodes;

        protected int argIndex;

        private boolean useBoundaryDeterminationRule = false;

        private boolean hasTooFewPoints = false;

        private Coordinate invalidPoint;

        private Map lineEdgeMap = new HashMap(); 

        private Geometry parentGeometry;

        double snapTolerance;

        public SnappingGeometryGraph(NodeFactory nodeFact, double tolerance,

                        int argIndex, Geometry parentGeometry) {

                super(argIndex, new GeometryCollection(new Geometry[0], parentGeometry.getFactory()));

                nodes = new SnappingNodeMap(nodeFact, tolerance);

                this.argIndex = argIndex;

                this.parentGeometry = parentGeometry;

                this.snapTolerance = tolerance;

                add(parentGeometry);

        }

        public void dumpNodes(){

                this.nodes.dump();

        }

        public SnappingGeometryGraph(double tolerance, int argIndex, Geometry parent) {

                super(argIndex, new GeometryCollection(new Geometry[0], parent.getFactory()));

                nodes = new SnappingNodeMap(new NodeFactory(), tolerance);

                this.argIndex = argIndex;

                this.snapTolerance = tolerance;

                add(parent);

        }

        public Collection getBoundaryNodes() {

                if (boundaryNodes == null)

                        boundaryNodes = nodes.getBoundaryNodes(argIndex);

                return boundaryNodes;

        }

        public Coordinate[] getBoundaryPoints() {

                Collection coll = getBoundaryNodes();

                Coordinate[] pts = new Coordinate[coll.size()];

                int i = 0;

                for (Iterator it = coll.iterator(); it.hasNext();) {

                        Node node = (Node) it.next();

                        pts[i++] = (Coordinate) node.getCoordinate().clone();

                }

                return pts;

        }

        public Iterator getNodeIterator() {

                return nodes.iterator();

        }

        public Collection getNodes() {

                return nodes.values();

        }

        public Node addNode(Node node) {

                return nodes.addNode(node);

        }

        public Node addNode(Coordinate coord) {

                return nodes.addNode(coord);

        }

        /**

         * @return the node if found; null otherwise

         */

        public Node find(Coordinate coord) {

                return nodes.find(coord);

        }

        public boolean isBoundaryNode(int geomIndex, Coordinate coord) {

                Node node = nodes.find(coord);

                if (node == null)

                        return false;

                Label label = node.getLabel();

                if (label != null && label.getLocation(geomIndex) == Location.BOUNDARY)

                        return true;

                return false;

        }

        public void add(EdgeEnd e) {

                nodes.add(e);

                edgeEndList.add(e);

        }

        /**

         * Link the DirectedEdges at the nodes of the graph. This allows clients to

         * link only a subset of nodes in the graph, for efficiency (because they

         * know that only a subset is of interest).

         */

        public void linkResultDirectedEdges() {

                for (Iterator nodeit = nodes.iterator(); nodeit.hasNext();) {

                        Node node = (Node) nodeit.next();

                        ((DirectedEdgeStar) node.getEdges()).linkResultDirectedEdges();

                }

        }

        /**

         * Link the DirectedEdges at the nodes of the graph. This allows clients to

         * link only a subset of nodes in the graph, for efficiency (because they

         * know that only a subset is of interest).

         */

        public void linkAllDirectedEdges() {

                for (Iterator nodeit = nodes.iterator(); nodeit.hasNext();) {

                        Node node = (Node) nodeit.next();

                        ((DirectedEdgeStar) node.getEdges()).linkAllDirectedEdges();

                }

        }

        /**

         * Returns the EdgeEnd which has edge e as its base edge (MD 18 Feb 2002 -

         * this should return a pair of edges)

         * 

         * @return the edge, if found <code>null</code> if the edge was not found

         */

        public EdgeEnd findEdgeEnd(Edge e) {

                for (Iterator i = getEdgeEnds().iterator(); i.hasNext();) {

                        EdgeEnd ee = (EdgeEnd) i.next();

                        if (ee.getEdge() == e)

                                return ee;

                }

                return null;

        }

        /**

         * Returns the edge whose first two coordinates are p0 and p1

         * 

         * @return the edge, if found <code>null</code> if the edge was not found

         */

        public Edge findEdge(Coordinate p0, Coordinate p1) {

                for (int i = 0; i < edges.size(); i++) {

                        Edge e = (Edge) edges.get(i);

                        Coordinate[] eCoord = e.getCoordinates();

                        if (p0.equals(eCoord[0]) && p1.equals(eCoord[1]))

                                return e;

                }

                return null;

        }

        /**

         * Returns the edge which starts at p0 and whose first segment is parallel

         * to p1

         * 

         * @return the edge, if found <code>null</code> if the edge was not found

         */

        public Edge findEdgeInSameDirection(Coordinate p0, Coordinate p1) {

                for (int i = 0; i < edges.size(); i++) {

                        Edge e = (Edge) edges.get(i);

                        Coordinate[] eCoord = e.getCoordinates();

                        if (matchInSameDirection(p0, p1, eCoord[0], eCoord[1]))

                                return e;

                        if (matchInSameDirection(p0, p1, eCoord[eCoord.length - 1],

                                        eCoord[eCoord.length - 2]))

                                return e;

                }

                return null;

        }

        /**

         * The coordinate pairs match if they define line segments lying in the same

         * direction. E.g. the segments are parallel and in the same quadrant (as

         * opposed to parallel and opposite!).

         */

        private boolean matchInSameDirection(Coordinate p0, Coordinate p1,

                        Coordinate ep0, Coordinate ep1) {

                if (!p0.equals(ep0))

                        return false;

                if (CGAlgorithms.computeOrientation(p0, p1, ep1) == CGAlgorithms.COLLINEAR

                                && Quadrant.quadrant(p0, p1) == Quadrant.quadrant(ep0, ep1))

                        return true;

                return false;

        }

        private void add(Geometry g)

          {

            if (g.isEmpty()) return;

            // check if this Geometry should obey the Boundary Determination Rule

            // all collections except MultiPolygons obey the rule

            if (g instanceof GeometryCollection

                && ! (g instanceof MultiPolygon))

                    useBoundaryDeterminationRule = true;

            if (g instanceof Polygon)                 addPolygon((Polygon) g);

                                // LineString also handles LinearRings

            else if (g instanceof LineString)         addLineString((LineString) g);

            else if (g instanceof Point)              addPoint((Point) g);

            else if (g instanceof MultiPoint)         addCollection((MultiPoint) g);

            else if (g instanceof MultiLineString)    addCollection((MultiLineString) g);

            else if (g instanceof MultiPolygon)       addCollection((MultiPolygon) g);

            else if (g instanceof GeometryCollection) addCollection((GeometryCollection) g);

            else  throw new UnsupportedOperationException(g.getClass().getName());

          }

          private void addCollection(GeometryCollection gc)

          {

            for (int i = 0; i < gc.getNumGeometries(); i++) {

              Geometry g = gc.getGeometryN(i);

              add(g);

            }

          }

          /**

           * Add a Point to the graph.

           */

          private void addPoint(Point p)

          {

            Coordinate coord = p.getCoordinate();

            insertPoint(argIndex, coord, Location.INTERIOR);

          }

          /**

           * The left and right topological location arguments assume that the ring is oriented CW.

           * If the ring is in the opposite orientation,

           * the left and right locations must be interchanged.

           */

          private void addPolygonRing(LinearRing lr, int cwLeft, int cwRight)

          {

            Coordinate[] coord = CoordinateArrays.removeRepeatedPoints(lr.getCoordinates());

            if (coord.length < 4) {

              hasTooFewPoints = true;

              invalidPoint = coord[0];

              return;

            }

            int left  = cwLeft;

            int right = cwRight;

            if (cga.isCCW(coord)) {

              left = cwRight;

              right = cwLeft;

            }

            SnappingEdge e = new SnappingEdge(coord,

                                new Label(argIndex, Location.BOUNDARY, left, right), this.snapTolerance);

            lineEdgeMap.put(lr, e);

            insertEdge(e);

            // insert the endpoint as a node, to mark that it is on the boundary

            insertPoint(argIndex, coord[0], Location.BOUNDARY);

          }

          private void addPolygon(Polygon p)

          {

            addPolygonRing(

                    (LinearRing) p.getExteriorRing(),

                    Location.EXTERIOR,

                    Location.INTERIOR);

            for (int i = 0; i < p.getNumInteriorRing(); i++) {

              // Holes are topologically labelled opposite to the shell, since

              // the interior of the polygon lies on their opposite side

              // (on the left, if the hole is oriented CW)

              addPolygonRing(

                    (LinearRing) p.getInteriorRingN(i),

                    Location.INTERIOR,

                    Location.EXTERIOR);

            }

          }

          private void addLineString(LineString line)

          {

            Coordinate[] coord = CoordinateArrays.removeRepeatedPoints(line.getCoordinates());

            if (coord.length < 2) {

              hasTooFewPoints = true;

              invalidPoint = coord[0];

              return;

            }

            // add the edge for the LineString

            // line edges do not have locations for their left and right sides

            SnappingEdge e = new SnappingEdge(coord, new Label(argIndex, Location.INTERIOR) , this.snapTolerance);

            lineEdgeMap.put(line, e);

            insertEdge(e);

            /**

             * Add the boundary points of the LineString, if any.

             * Even if the LineString is closed, add both points as if they were endpoints.

             * This allows for the case that the node already exists and is a boundary point.

             */

            Assert.isTrue(coord.length >= 2, "found LineString with single point");

            insertBoundaryPoint(argIndex, coord[0]);

            insertBoundaryPoint(argIndex, coord[coord.length - 1]);

          }

          /**

           * Add an Edge computed externally.  The label on the Edge is assumed

           * to be correct.

           */

          public void addEdge(Edge e)

          {

            insertEdge(e);

            Coordinate[] coord = e.getCoordinates();

            // insert the endpoint as a node, to mark that it is on the boundary

            insertPoint(argIndex, coord[0], Location.BOUNDARY);

            insertPoint(argIndex, coord[coord.length - 1], Location.BOUNDARY);

          }

          /**

           * Add a point computed externally.  The point is assumed to be a

           * Point Geometry part, which has a location of INTERIOR.

           */

          public void addPoint(Coordinate pt)

          {

            insertPoint(argIndex, pt, Location.INTERIOR);

          }

          /**

           * Compute self-nodes, taking advantage of the Geometry type to

           * minimize the number of intersection tests.  (E.g. rings are

           * not tested for self-intersection, since they are assumed to be valid).

           * @param li the LineIntersector to use

           * @param computeRingSelfNodes if <false>, intersection checks are optimized to not test rings for self-intersection

           * @return the SegmentIntersector used, containing information about the intersections found

           */

          public SegmentIntersector computeSelfNodes(LineIntersector li, boolean computeRingSelfNodes)

          {

            SegmentIntersector si = new SegmentIntersector(li, true, false);

            SnapSimpleMCSweepLineIntersector esi = new SnapSimpleMCSweepLineIntersector();

            // optimized test for Polygons and Rings

            if (! computeRingSelfNodes

                && (parentGeometry instanceof LinearRing

                || parentGeometry instanceof Polygon

                || parentGeometry instanceof MultiPolygon)) {

              esi.computeIntersections(edges, si, false);

            }

            else {

              esi.computeIntersections(edges, si, true);

            }

            addSelfIntersectionNodes(argIndex);

            return si;

          }

          public SegmentIntersector computeEdgeIntersections(

            GeometryGraph g,

            LineIntersector li,

            boolean includeProper)

          {

            SegmentIntersector si = new SegmentIntersector(li, includeProper, true);

            si.setBoundaryNodes(this.getBoundaryNodes(), g.getBoundaryNodes());

            SnapSimpleMCSweepLineIntersector esi = new SnapSimpleMCSweepLineIntersector();

            esi.computeIntersections(edges, g.edges, si);

            return si;

          }

          private void addSelfIntersectionNodes(int argIndex)

          {

            for (Iterator i = edges.iterator(); i.hasNext(); ) {

              Edge e = (Edge) i.next();

              int eLoc = e.getLabel().getLocation(argIndex);

              for (Iterator eiIt = e.eiList.iterator(); eiIt.hasNext(); ) {

                EdgeIntersection ei = (EdgeIntersection) eiIt.next();

                addSelfIntersectionNode(argIndex, ei.coord, eLoc);

              }

            }

          }

          /**

           * Add a node for a self-intersection.

           * If the node is a potential boundary node (e.g. came from an edge which

           * is a boundary) then insert it as a potential boundary node.

           * Otherwise, just add it as a regular node.

           */

          private void addSelfIntersectionNode(int argIndex, Coordinate coord, int loc)

          {

            // if this node is already a boundary node, don't change it

            if (isBoundaryNode(argIndex, coord)) return;

            if (loc == Location.BOUNDARY && useBoundaryDeterminationRule)

                insertBoundaryPoint(argIndex, coord);

            else

              insertPoint(argIndex, coord, loc);

          }

          private void insertPoint(int argIndex, Coordinate coord, int onLocation)

          {

            Node n = nodes.addNode(coord);

            Label lbl = n.getLabel();

            if (lbl == null) {

              n.label = new Label(argIndex, onLocation);

            }

            else

              lbl.setLocation(argIndex, onLocation);

          }

          /**

           * Adds points using the mod-2 rule of SFS.  This is used to add the boundary

           * points of dim-1 geometries (Curves/MultiCurves).  According to the SFS,

           * an endpoint of a Curve is on the boundary

           * iff if it is in the boundaries of an odd number of Geometries

           */

          private void insertBoundaryPoint(int argIndex, Coordinate coord)

          {

            Node n = nodes.addNode(coord);

            Label lbl = n.getLabel();

            // the new point to insert is on a boundary

            int boundaryCount = 1;

            // determine the current location for the point (if any)

            int loc = Location.NONE;

            if (lbl != null) loc = lbl.getLocation(argIndex, Position.ON);

            if (loc == Location.BOUNDARY) boundaryCount++;

            // determine the boundary status of the point according to the Boundary Determination Rule

            int newLoc = determineBoundary(boundaryCount);

            lbl.setLocation(argIndex, newLoc);

          }

          public void computeSplitEdges(List edgelist)

          {

            for (Iterator i = edges.iterator(); i.hasNext(); ) {

              SnappingEdge e = (SnappingEdge) i.next();

              e.getEdgeIntersectionList().addSplitEdges(edgelist);

            }

          }

}