--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gnv-artifacts/src/main/java/de/intevation/gnv/raster/PolygonDatasetProducer.java	Sat Dec 26 15:32:08 2009 +0000
@@ -0,0 +1,97 @@
+package de.intevation.gnv.raster;
+
+import java.util.List;
+import java.util.HashMap;
+
+import gnu.trove.TDoubleArrayList;
+
+import de.intevation.gnv.raster.Vectorizer.RingsHandler;
+import de.intevation.gnv.raster.Vectorizer.Edge;
+
+import de.intevation.gnv.jfreechart.PolygonSeries;
+import de.intevation.gnv.jfreechart.PolygonDataset;
+import de.intevation.gnv.jfreechart.CompactXYItems;
+
+public class PolygonDatasetProducer
+implements   RingsHandler
+{
+    protected double minX;
+    protected double minY;
+
+    protected double maxX;
+    protected double maxY;
+
+    protected HashMap<Integer, PolygonSeries> polygonSeries;
+
+    protected PolygonDatasetProducer() {
+    }
+
+    public PolygonDatasetProducer(
+        double minX, double minY,
+        double maxX, double maxY
+
+    ) {
+        this.minX = minX;
+        this.minY = minY;
+        this.maxX = maxX;
+        this.maxY = maxY;
+
+        polygonSeries = new HashMap<Integer, PolygonSeries>();
+    }
+
+    public void handleRings(
+        List<Edge> rings, 
+        int        value, 
+        int        width,
+        int        height
+    ) {
+        if (value == -1) {
+            return;
+        }
+
+        Integer v = Integer.valueOf(value);
+
+        PolygonSeries ps = (PolygonSeries)polygonSeries.get(v);
+
+        if (ps == null) {
+            polygonSeries.put(v, ps = new PolygonSeries());
+            ps.setAttribute("fill", v);
+        }
+
+        TDoubleArrayList vertices = new TDoubleArrayList();
+
+        /* minX = 0*m1 + b1 <=> b1 = minX
+         * maxX = (width-1)*m1 + b1
+         * m1 = (maxX - minX)/(width-1)
+         */
+
+         double b1 = minX;
+         double m1 = width != 1
+            ? (maxX - minX)/(width-1)
+            : 0d;
+
+         double b2 = minY;
+         double m2 = height != 1
+            ? (maxY - minY)/(height-1)
+            : 0d;
+
+        for (Edge head: rings) {
+            Edge current = head;
+            do {
+                double x = m1*(current.a % width) + b1;
+                double y = m2*(current.a / width) + b2;
+                vertices.add(x);
+                vertices.add(y);
+                current = current.next;
+            }
+            while (current != head);
+            ps.addRing(new CompactXYItems(vertices.toNativeArray()));
+            vertices.clear();
+        }
+    }
+
+    public PolygonDataset getPolygonDataset() {
+        return new PolygonDataset(polygonSeries.values());
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8: