sascha@465: package de.intevation.gnv.raster;
sascha@465: 
sascha@465: import de.intevation.gnv.math.IJKey;
sascha@465: 
sascha@465: import de.intevation.gnv.raster.Vectorizer.Edge;
sascha@465: 
sascha@779: import gnu.trove.TIntHashSet;
sascha@779: import gnu.trove.TIntObjectHashMap;
sascha@779: import gnu.trove.TObjectProcedure;
sascha@779: 
sascha@779: import java.util.ArrayList;
sascha@779: import java.util.HashMap;
sascha@779: import java.util.HashSet;
sascha@779: import java.util.List;
sascha@779: 
sascha@465: /**
sascha@802:  * Vectorizer backend to generate iso lines as line strings
sascha@801:  * and custom labels on the chart.
sascha@801:  *
sascha@780:  * @author <a href="mailto:sascha.teichmann@intevation.de">Sascha L. Teichmann</a>
sascha@465:  */
sascha@465: public class IsoProducer
sascha@465: extends      AbstractProducer
sascha@465: {
sascha@801:     /**
sascha@801:      * Iso lines separate two neighbors. This interface decouples
sascha@801:      * the generation of a suitable label for these to neighbors.
sascha@801:      */
sascha@465:     public interface AttributeGenerator {
sascha@465: 
sascha@801:         /**
sascha@801:          * Generate attribute show as label for two given neighbors.
sascha@801:          * @param neighbor1 The first neighbor.
sascha@801:          * @param neighbor2 The second neighbor.
sascha@801:          * @return The label attribute.
sascha@801:          */
sascha@465:         Object generateAttribute(int neighbor1, int neighbor2);
sascha@465: 
sascha@465:     } // interface AttributeGenerator
sascha@465: 
sascha@801:     /**
sascha@801:      * Internal map of open edge to neighbor attributes.
sascha@801:      */
sascha@465:     protected HashMap<Edge, Integer>            open;
sascha@801:     /**
sascha@801:      * Internal map to associate neighbors with open edges.
sascha@801:      */
sascha@465:     protected HashMap<IJKey, TIntObjectHashMap> commonOpen;
sascha@801:     /**
sascha@801:      * Internal map to associate neighbors with complete rings.
sascha@801:      */
sascha@465:     protected HashMap<IJKey, ArrayList<Edge>>   complete;
sascha@465: 
sascha@801:     /**
sascha@801:      * Width of the index space.
sascha@801:      */
sascha@465:     protected int    width;
sascha@801:     /**
sascha@801:      * Height of the index space.
sascha@801:      */
sascha@465:     protected int    height;
sascha@465: 
sascha@801:     /**
sascha@801:      * Constructor with a given world bounding box.
sascha@801:      * @param minX Min x coord of the world.
sascha@801:      * @param minY Min y coord of the world.
sascha@801:      * @param maxX Max x coord of the world.
sascha@801:      * @param maxY Max y coord of the world.
sascha@801:      */
sascha@465:     public IsoProducer(
sascha@465:         double minX, double minY,
sascha@465:         double maxX, double maxY
sascha@465:     ) {
sascha@465:         super(minX, minY, maxX, maxY);
sascha@465: 
sascha@465:         open       = new HashMap<Edge, Integer>();
sascha@465:         commonOpen = new HashMap<IJKey, TIntObjectHashMap>();
sascha@465:         complete   = new HashMap<IJKey, ArrayList<Edge>>();
sascha@465:     }
sascha@465: 
sascha@465:     public void handleRings(
sascha@778:         List<Edge> rings,
sascha@778:         int        value,
sascha@465:         int        width,
sascha@465:         int        height
sascha@465:     ) {
sascha@465:         if (value == -1) {
sascha@465:             return;
sascha@465:         }
sascha@465:         this.width  = width;
sascha@465:         this.height = height;
sascha@465: 
sascha@465:         Integer v = Integer.valueOf(value);
sascha@465: 
sascha@465:         for (Edge head: rings) {
sascha@465:             Edge current = head;
sascha@465:             do {
sascha@465:                 Integer neighbor = open.remove(current);
sascha@465: 
sascha@465:                 if (neighbor != null) {
sascha@465:                     IJKey pair = new IJKey(value, neighbor.intValue());
sascha@465:                     pair.sort();
sascha@465: 
sascha@465:                     TIntObjectHashMap co = commonOpen.get(pair);
sascha@465: 
sascha@465:                     if (co == null) {
sascha@465:                         commonOpen.put(pair, co = new TIntObjectHashMap());
sascha@465:                     }
sascha@465: 
sascha@465:                     Edge edge = new Edge(current);
sascha@465: 
sascha@465:                     Edge otherA = (Edge)co.remove(edge.a);
sascha@465:                     if (otherA != null) {
sascha@465:                         otherA.chain(edge, edge.a);
sascha@465:                     }
sascha@465: 
sascha@465:                     Edge otherB = (Edge)co.remove(edge.b);
sascha@465:                     if (otherB != null) {
sascha@465:                         otherB.chain(edge, edge.b);
sascha@465:                     }
sascha@465: 
sascha@465:                     if (edge.isComplete()) {
sascha@465:                         ArrayList list = complete.get(pair);
sascha@465:                         if (list == null) {
sascha@465:                             complete.put(pair, list = new ArrayList());
sascha@465:                         }
sascha@465:                         list.add(Vectorizer.simplify(edge, width));
sascha@465:                     }
sascha@465:                     else {
sascha@465:                         if (otherA == null) {
sascha@465:                             co.put(edge.a, edge);
sascha@465:                         }
sascha@465:                         if (otherB == null) {
sascha@465:                             co.put(edge.b, edge);
sascha@465:                         }
sascha@465:                     }
sascha@465:                 }
sascha@465:                 else {
sascha@465:                     Edge edge = new Edge(current.b, current.a);
sascha@465:                     open.put(edge, v);
sascha@465:                 }
sascha@465: 
sascha@465:                 current = current.next;
sascha@465:             }
sascha@465:             while (current != head);
sascha@465:         } // for all rings
sascha@465: 
sascha@465:     } // handleRings
sascha@465: 
sascha@801:     /**
sascha@801:      * Join the pairs of neighbors i,j to have a distinct set.
sascha@801:      * @return The distinct pairs of neighbors.
sascha@801:      */
sascha@465:     protected HashSet<IJKey> joinPairs() {
sascha@465:         HashSet<IJKey> pairs = new HashSet<IJKey>();
sascha@465:         pairs.addAll(complete  .keySet());
sascha@465:         pairs.addAll(commonOpen.keySet());
sascha@465:         return pairs;
sascha@465:     }
sascha@465: 
sascha@801:     /**
sascha@801:      * Filter out the head list from the open edge lists.
sascha@801:      * @param map Map of end and head lists.
sascha@801:      * @return list of only head lists.
sascha@801:      */
sascha@465:     protected static ArrayList<Edge> headList(TIntObjectHashMap map) {
sascha@465:         final ArrayList<Edge> headList = new ArrayList<Edge>();
sascha@465:         map.forEachValue(new TObjectProcedure() {
sascha@465:             TIntHashSet headSet = new TIntHashSet();
sascha@465:             public boolean execute(Object value) {
sascha@465:                 Edge head = ((Edge)value).head();
sascha@465:                 if (headSet.add(head.a)) {
sascha@465:                     headList.add(head);
sascha@465:                 }
sascha@465:                 return true;
sascha@465:             }
sascha@465:         });
sascha@465:         return headList;
sascha@465:     }
sascha@465: 
sascha@801:     /**
sascha@801:      * Reset internal data structures to save some memory.
sascha@801:      */
sascha@465:     public void clear() {
sascha@465:         open.clear();
sascha@465:         complete.clear();
sascha@465:         commonOpen.clear();
sascha@465:     }
sascha@465: }
sascha@465: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :