--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gnv-artifacts/src/main/java/de/intevation/gnv/raster/JTSMultiLineStringProducer.java	Fri Sep 28 12:13:56 2012 +0200
@@ -0,0 +1,239 @@
+package de.intevation.gnv.raster;
+
+import com.vividsolutions.jts.geom.Coordinate;
+import com.vividsolutions.jts.geom.Geometry;
+import com.vividsolutions.jts.geom.GeometryFactory;
+import com.vividsolutions.jts.geom.LineString;
+import com.vividsolutions.jts.geom.MultiLineString;
+import com.vividsolutions.jts.geom.Polygon;
+import com.vividsolutions.jts.geom.TopologyException;
+
+import de.intevation.gnv.math.IJKey;
+
+import de.intevation.gnv.raster.Vectorizer.Edge;
+
+import de.intevation.gnv.utils.Pair;
+
+import gnu.trove.TIntObjectHashMap;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.log4j.Logger;
+
+/**
+ * Vectorizer backend to generated iso lines in form of
+ * JTS multi linestrings.
+ *
+ * @author <a href="mailto:sascha.teichmann@intevation.de">Sascha L. Teichmann</a>
+ */
+public class JTSMultiLineStringProducer
+extends      IsoProducer
+{
+    private static Logger log = Logger.getLogger(
+        JTSMultiLineStringProducer.class);
+
+    /**
+     * The JTS geometry factory of this producer.
+     */
+    protected GeometryFactory geometryFactory;
+
+    /**
+     * The polygon used to clip the produced multe line strings.
+     */
+    protected Polygon clip;
+
+    /**
+     * Constructor to create a JTSMultiLineStringProducer with
+     * a given clipping polygon and a world bounding box.
+     * @param clip The clipping polygon.
+     * @param minX Min x coord of the world.
+     * @param minY Min y coord of the world.
+     * @param maxX Max x coord of the world.
+     * @param maxY Max y coord of the world.
+     */
+    public JTSMultiLineStringProducer(
+        Polygon clip,
+        double minX, double minY,
+        double maxX, double maxY
+    ) {
+        this(
+            clip,
+            // XXX: Geotools crashes if only using a 2d packed data format!
+            JTSMultiPolygonProducer.createDefaultGeometryFactory(3),
+            minX, minY,
+            maxX, maxY);
+    }
+
+    /**
+     * Constructor to create a JTSMultiLineStringProducer with
+     * a given clipping polygon, a geometry factory
+     * and a world bounding box.
+     * @param clip The clipping polygon.
+     * @param geometryFactory The geometry factory.
+     * @param minX Min x coord of the world.
+     * @param minY Min y coord of the world.
+     * @param maxX Max x coord of the world.
+     * @param maxY Max y coord of the world.
+     */
+    public JTSMultiLineStringProducer(
+        Polygon clip,
+        GeometryFactory geometryFactory,
+        double minX, double minY,
+        double maxX, double maxY
+    ) {
+        super(minX, minY, maxX, maxY);
+        this.clip = clip;
+        this.geometryFactory = geometryFactory;
+    }
+
+    /**
+     * Clips a given line string against the clippin polygon. The
+     * result is stored in the given list of line strings.
+     * @param lineString The line string to be clipped.
+     * @param lineStrings The result line string list.
+     */
+    protected void clipLineString(
+        LineString            lineString,
+        ArrayList<LineString> lineStrings
+    ) {
+        if (clip == null) {
+            lineStrings.add(lineString);
+            return;
+        }
+
+        if (!lineString.intersects(clip)) {
+            return;
+        }
+
+        try {
+            Geometry result = lineString.intersection(clip);
+
+            if (result instanceof LineString) {
+                lineStrings.add((LineString)result);
+            }
+            else if (result instanceof MultiLineString) {
+                MultiLineString mls = (MultiLineString)result;
+                for (int i = 0, N = mls.getNumGeometries(); i < N; ++i) {
+                    Geometry g = mls.getGeometryN(i);
+                    if (g instanceof LineString) {
+                        lineStrings.add((LineString)g);
+                    }
+                    else {
+                        log.warn("cannot handle geometry " + g.getClass());
+                    }
+                }
+            }
+            else {
+                log.warn("cannot handle " + result.getClass());
+            }
+        }
+        catch (TopologyException te) {
+            log.error(te.getLocalizedMessage(), te);
+            lineStrings.add(lineString);
+        }
+    }
+
+    /**
+     * Returns a list of pairs attribute -&gt; multi line string.
+     * All line strings produced are grouped by there attribute
+     * which is generated with the given attribute generator.
+     * @param attributeGenerator The attribute generator.
+     * @return The list of attribute/multi line strings.
+     */
+    public List<Pair<Object, MultiLineString>> getMultiLineStrings(
+        AttributeGenerator attributeGenerator
+    ) {
+        ArrayList<Pair<Object, MultiLineString>> multiLineStrings =
+            new ArrayList<Pair<Object, MultiLineString>>();
+
+        double b1 = minX;
+        double m1 = width != 1
+            ? (maxX - minX)/(width-1)
+            : 0d;
+
+         double b2 = minY;
+         double m2 = height != 1
+            ? (maxY - minY)/(height-1)
+            : 0d;
+
+        ArrayList<Coordinate> coordinates = new ArrayList<Coordinate>();
+
+        for (IJKey key: joinPairs()) {
+            ArrayList<LineString> lineStrings = new ArrayList<LineString>();
+
+            // process complete
+            ArrayList<Edge> completeList = complete.get(key);
+            if (completeList != null) {
+                for (Edge head: completeList) {
+                    Edge current = head;
+                    do {
+                        coordinates.add(new Coordinate(
+                            m1*(current.a % width) + b1,
+                            m2*(current.a / width) + b2));
+                    }
+                    while ((current = current.next) != head);
+                    // add head again to close shape
+                    coordinates.add(new Coordinate(
+                        m1*(head.a % width) + b1,
+                        m2*(head.a / width) + b2));
+
+                    clipLineString(
+                        geometryFactory.createLineString(
+                            coordinates.toArray(
+                                new Coordinate[coordinates.size()])),
+                        lineStrings);
+
+                    coordinates.clear();
+                }
+            }
+
+            // process open
+            TIntObjectHashMap map = commonOpen.get(key);
+
+            if (map != null) {
+                for (Edge head: headList(map)) {
+
+                    head = Vectorizer.simplify(head, width);
+                    Edge current = head, last = head;
+                    do {
+                        coordinates.add(new Coordinate(
+                            m1*(current.a % width) + b1,
+                            m2*(current.a / width) + b2));
+                        last = current;
+                    }
+                    while ((current = current.next) != null);
+                    // add b from tail
+                    coordinates.add(new Coordinate(
+                        m1*(last.b % width) + b1,
+                        m2*(last.b / width) + b2));
+
+                    clipLineString(
+                        geometryFactory.createLineString(
+                            coordinates.toArray(
+                                new Coordinate[coordinates.size()])),
+                        lineStrings);
+
+                    coordinates.clear();
+                } // for all in common open
+            } // if map defined for key
+
+			if (!lineStrings.isEmpty()) {
+                MultiLineString multiLineString =
+                    geometryFactory.createMultiLineString(
+                        lineStrings.toArray(
+                            new LineString[lineStrings.size()]));
+                lineStrings.clear();
+                Object attribute = attributeGenerator != null
+                    ? attributeGenerator.generateAttribute(key.i, key.j)
+                    : key;
+                multiLineStrings.add(new Pair<Object, MultiLineString>(
+                    attribute,
+                    multiLineString));
+			}
+        } // for all pairs
+
+        return multiLineStrings;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :