--- a/flys-backend/ChangeLog	Mon Sep 26 15:26:44 2011 +0000
+++ b/flys-backend/ChangeLog	Tue Sep 27 13:37:34 2011 +0000
@@ -1,3 +1,8 @@
+2011-09-27	Sascha L. Teichmann	<sascha.teichmann@intevation.de>
+
+	* src/main/java/de/intevation/flys/model/CrossSectionLine.java:
+	  Moved some logic from cross section demo app to this model.
+	
 2011-09-26  Ingo Weinzierl <ingo@intevation.de>
 
 	* src/main/java/de/intevation/flys/model/CrossSectionTrack.java:

--- a/flys-backend/src/main/java/de/intevation/flys/model/CrossSectionLine.java	Mon Sep 26 15:26:44 2011 +0000
+++ b/flys-backend/src/main/java/de/intevation/flys/model/CrossSectionLine.java	Tue Sep 27 13:37:34 2011 +0000
@@ -4,7 +4,12 @@
 
 import java.math.BigDecimal;
 
+import java.util.ArrayList;
 import java.util.List;
+import java.util.Collections;
+import java.util.Comparator;
+
+import java.awt.geom.Point2D;
 
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -17,17 +22,47 @@
 import javax.persistence.OneToMany;
 import javax.persistence.JoinColumn;
 
+import org.apache.log4j.Logger;
+
 @Entity
 @Table(name = "cross_section_lines")
 public class CrossSectionLine
 implements   Serializable
 {
+    private static Logger logger = Logger.getLogger(CrossSectionLine.class);
+
+    public static final double EPSILON   = 1e-4;
+
+    public static final double TOO_SMALL = 0.2;
+    public static final double TOO_BIG   = 500;
+
     private Integer                 id;
     private BigDecimal              km;
     private CrossSection            crossSection;
 
     private List<CrossSectionPoint> points;
 
+    public static final Comparator<CrossSectionPoint> COL_POS_CMP =
+        new Comparator<CrossSectionPoint>() {
+            @Override
+            public int compare(CrossSectionPoint a, CrossSectionPoint b) {
+                double xa = a.getX().doubleValue();
+                double xb = b.getX().doubleValue();
+                double d = xa - xb;
+                if (d < -EPSILON) return -1;
+                if (d > +EPSILON) return +1;
+                int diff = a.getColPos() - b.getColPos();
+                return diff < 0 ? -1 : diff > 0 ? +1 : 0;
+            }
+        };
+
+
+    public static final boolean isValid(double x) {
+        x = Math.abs(x);
+        return x > TOO_SMALL && x < TOO_BIG;
+    }    
+
+
     public CrossSectionLine() {
     }
 
@@ -81,5 +116,62 @@
     public void setPoints(List<CrossSectionPoint> points) {
         this.points = points;
     }
+
+
+    public List<Point2D> fetchCrossSectionLinesPoints() {
+        List<Point2D> points = new ArrayList<Point2D>();
+
+        List<CrossSectionPoint> linePoints = getPoints();
+
+        if (linePoints.isEmpty()) {
+            logger.info("No points in selected CrossSectionLine.");
+            return points;
+        }
+
+        linePoints = new ArrayList(linePoints);
+        Collections.sort(linePoints, COL_POS_CMP);
+
+        for (CrossSectionPoint p: linePoints) {
+            double x = p.getX().doubleValue();
+            double y = p.getY().doubleValue();
+            if (isValid(x) && isValid(y)) {
+                points.add(new Point2D.Double(x, y));
+            }
+        }
+
+        return points;
+    }
+
+    public double [][] fetchCrossSectionProfile() {
+        return fetchCrossSectionProfile(fetchCrossSectionLinesPoints());
+    }
+
+    public static double [][] fetchCrossSectionProfile(List<Point2D> points) {
+
+        int P = points.size();
+
+        double [] xs = new double[P];
+        double [] ys = new double[P];
+
+        if (P > 0) {
+            xs[0] = points.get(0).getX();
+            ys[0] = points.get(0).getY();
+
+            for (int i = 1; i < P; i++) {
+                Point2D p = points.get(i);
+                double x = p.getX();
+                double y = p.getY();
+
+                if (x <= xs[i-1]) {
+                    x = xs[i-1] + EPSILON;
+                }
+
+                xs[i] = x;
+                ys[i] = y; 
+            }
+        }
+
+        return new double [][] { xs, ys };
+    }
 }
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