sascha@465: package de.intevation.gnv.raster;
sascha@465: 
sascha@465: import com.vividsolutions.jts.algorithm.CGAlgorithms;
sascha@465: 
sascha@499: import com.vividsolutions.jts.geom.Coordinate;
sascha@499: import com.vividsolutions.jts.geom.Geometry;
sascha@499: import com.vividsolutions.jts.geom.GeometryFactory;
sascha@499: import com.vividsolutions.jts.geom.LinearRing;
sascha@499: import com.vividsolutions.jts.geom.MultiPolygon;
sascha@499: import com.vividsolutions.jts.geom.Polygon;
sascha@499: import com.vividsolutions.jts.geom.PrecisionModel;
sascha@499: import com.vividsolutions.jts.geom.TopologyException;
sascha@499: 
sascha@465: import com.vividsolutions.jts.geom.impl.PackedCoordinateSequenceFactory;
sascha@465: 
sascha@499: import de.intevation.gnv.raster.Vectorizer.Edge;
sascha@499: 
sascha@499: import java.util.ArrayList;
sascha@499: import java.util.HashMap;
sascha@499: import java.util.List;
sascha@499: import java.util.Map;
sascha@499: import java.util.TreeMap;
sascha@499: 
sascha@465: import org.apache.log4j.Logger;
sascha@465: 
sascha@465: /**
sascha@465:  * @author Sascha L. Teichmann (sascha.teichmann@intevation.de)
sascha@465:  */
sascha@465: public class JTSMultiPolygonProducer
sascha@465: extends      AbstractProducer
sascha@465: {
sascha@465:     private static Logger log = Logger.getLogger(
sascha@465:         JTSMultiPolygonProducer.class);
sascha@465: 
sascha@465:     public static final int SRID_WGS84 = 4326;
sascha@465: 
sascha@465:     public interface ValueConverter {
sascha@465: 
sascha@465:         Integer convert(Integer value);
sascha@465: 
sascha@465:     } // interface ValueConverter
sascha@465: 
sascha@465:     protected GeometryFactory geometryFactory;
sascha@465: 
sascha@499:     protected Polygon clip;
sascha@499: 
sascha@465:     protected HashMap<Integer, ArrayList<Polygon>> valueToPolygons;
sascha@465: 
sascha@465:     public JTSMultiPolygonProducer() {
sascha@465:     }
sascha@465: 
sascha@465:     public JTSMultiPolygonProducer(
sascha@499:         Polygon clip,
sascha@465:         double minX, double minY,
sascha@465:         double maxX, double maxY
sascha@465:     ) {
sascha@465:         this(
sascha@499:             clip,
sascha@465:             createDefaultGeometryFactory(),
sascha@465:             minX, minY,
sascha@465:             maxX, maxY);
sascha@465:     }
sascha@465: 
sascha@465:     public JTSMultiPolygonProducer(
sascha@499:         Polygon clip,
sascha@465:         GeometryFactory geometryFactory,
sascha@465:         double minX, double minY,
sascha@465:         double maxX, double maxY
sascha@465:     ) {
sascha@465:         super(minX, minY, maxX, maxY);
sascha@499:         this.clip = clip;
sascha@465:         this.geometryFactory = geometryFactory;
sascha@465:         valueToPolygons = new HashMap<Integer, ArrayList<Polygon>>();
sascha@465:     }
sascha@465: 
sascha@465:     public static GeometryFactory createDefaultGeometryFactory() {
sascha@499:         return createDefaultGeometryFactory(3);
sascha@498:     }
sascha@498: 
sascha@498:     public static GeometryFactory createDefaultGeometryFactory(int dim) {
sascha@465:         return new GeometryFactory(
sascha@465:             new PrecisionModel(
sascha@465:                 PrecisionModel.FLOATING),
sascha@465:             SRID_WGS84,
sascha@465:             new PackedCoordinateSequenceFactory(
sascha@465:                 PackedCoordinateSequenceFactory.DOUBLE,
sascha@498:                 dim));
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: 
sascha@465:         double b1 = minX;
sascha@465:         double m1 = width != 1
sascha@465:            ? (maxX - minX)/(width-1)
sascha@465:            : 0d;
sascha@465: 
sascha@465:         double b2 = minY;
sascha@465:         double m2 = height != 1
sascha@465:            ? (maxY - minY)/(height-1)
sascha@465:            : 0d;
sascha@465: 
sascha@465:         ArrayList<Coordinate> vertices = new ArrayList<Coordinate>();
sascha@465: 
sascha@465:         LinearRing shell = null;
sascha@465:         ArrayList<LinearRing> holes = new ArrayList<LinearRing>();
sascha@465: 
sascha@465:         for (Edge head: rings) {
sascha@465:             Edge current = head;
sascha@465:             do {
sascha@465:                 vertices.add(new Coordinate(
sascha@465:                     m1*(current.a % width) + b1,
sascha@465:                     m2*(current.a / width) + b2));
sascha@465:             }
sascha@495:             while ((current = current.prev) != head);
sascha@465:             vertices.add(new Coordinate(
sascha@465:                 m1*(head.a % width) + b1,
sascha@465:                 m2*(head.a / width) + b2));
sascha@465: 
sascha@465:             Coordinate [] coordinates =
sascha@465:                 vertices.toArray(new Coordinate[vertices.size()]);
sascha@465: 
sascha@465:             vertices.clear();
sascha@465: 
sascha@465:             LinearRing ring = geometryFactory.createLinearRing(
sascha@465:                 coordinates);
sascha@465: 
sascha@465:             if (CGAlgorithms.isCCW(coordinates)) {
sascha@465:                 shell = ring;
sascha@465:             }
sascha@465:             else {
sascha@465:                 holes.add(ring);
sascha@465:             }
sascha@465:         }
sascha@465: 
sascha@465:         if (shell == null) {
sascha@465:             log.error("polygon has no shell");
sascha@465:             return;
sascha@465:         }
sascha@465: 
sascha@465:         Polygon polygon = geometryFactory.createPolygon(
sascha@465:             shell,
sascha@465:             holes.toArray(new LinearRing[holes.size()]));
sascha@465: 
sascha@499:         if (clip == null || clip.intersects(polygon)) {
sascha@499:             Integer v = Integer.valueOf(value);
sascha@499: 
sascha@499:             ArrayList<Polygon> polygons = valueToPolygons.get(v);
sascha@499: 
sascha@499:             if (polygons == null) {
sascha@499:                 valueToPolygons.put(v, polygons = new ArrayList<Polygon>());
sascha@499:             }
sascha@499: 
sascha@499:             polygons.add(polygon);
sascha@499:         }
sascha@465:     }
sascha@465: 
sascha@465:     public Map<Integer, MultiPolygon> getMultiPolygons() {
sascha@465:         return getMultiPolygons(null);
sascha@465:     }
sascha@465: 
sascha@499:     protected MultiPolygon flattenCollection(Geometry result) {
sascha@499: 
sascha@499:         if (result instanceof MultiPolygon) {
sascha@499:             return (MultiPolygon)result;
sascha@499:         }
sascha@499: 
sascha@499:         if (result instanceof Polygon) {
sascha@499:             return geometryFactory.createMultiPolygon(
sascha@499:                 new Polygon[] { (Polygon)result });
sascha@499:         }
sascha@499: 
sascha@499:         log.warn("cannot handle " + result.getClass());
sascha@499: 
sascha@499:         return null;
sascha@499:     }
sascha@499: 
sascha@465:     public Map<Integer, MultiPolygon> getMultiPolygons(
sascha@465:         ValueConverter valueConverter
sascha@465:     ) {
sascha@465:         TreeMap<Integer, MultiPolygon> multiPolygons =
sascha@465:             new TreeMap<Integer, MultiPolygon>();
sascha@465: 
sascha@465:         for (Map.Entry<Integer, ArrayList<Polygon>> entry:
sascha@465:             valueToPolygons.entrySet()
sascha@465:         ) {
sascha@465:             ArrayList<Polygon> polygons = entry.getValue();
sascha@465: 
sascha@465:             Integer value = valueConverter != null
sascha@465:                 ? valueConverter.convert(entry.getKey())
sascha@465:                 : entry.getKey();
sascha@465: 
sascha@499:             MultiPolygon mp = geometryFactory.createMultiPolygon(
sascha@499:                 polygons.toArray(new Polygon[polygons.size()]));
sascha@499: 
sascha@499:             if (clip != null) {
sascha@499:                 try {
sascha@499:                     Geometry result = mp.intersection(clip);
sascha@499: 
sascha@499:                     MultiPolygon mp2 = flattenCollection(result);
sascha@499: 
sascha@499:                     if (mp2 != null) { mp = mp2; }
sascha@499:                 }
sascha@499:                 catch (TopologyException te) {
sascha@499:                     log.error(te.getLocalizedMessage(), te);
sascha@499:                 }
sascha@499:             }
sascha@499:             multiPolygons.put(value, mp);
sascha@465:         }
sascha@465: 
sascha@465:         return multiPolygons;
sascha@465:     }
sascha@465: 
sascha@465:     public void clear() {
sascha@465:         valueToPolygons.clear();
sascha@465:     }
sascha@465: }
sascha@465: // vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :