Index: /applications/editors/josm/plugins/validator/src/org/openstreetmap/josm/plugins/validator/tests/CrossingSegments.java
===================================================================
--- /applications/editors/josm/plugins/validator/src/org/openstreetmap/josm/plugins/validator/tests/CrossingSegments.java	(revision 3259)
+++ /applications/editors/josm/plugins/validator/src/org/openstreetmap/josm/plugins/validator/tests/CrossingSegments.java	(revision 3260)
@@ -3,15 +3,11 @@
 import static org.openstreetmap.josm.tools.I18n.tr;
 
-import java.awt.Point;
 import java.awt.geom.Line2D;
 import java.awt.geom.Point2D;
 import java.util.*;
 
-import org.openstreetmap.josm.data.coor.EastNorth;
-import org.openstreetmap.josm.data.coor.LatLon;
 import org.openstreetmap.josm.data.osm.*;
-import org.openstreetmap.josm.plugins.validator.Severity;
-import org.openstreetmap.josm.plugins.validator.Test;
-import org.openstreetmap.josm.plugins.validator.TestError;
+import org.openstreetmap.josm.plugins.validator.*;
+import org.openstreetmap.josm.plugins.validator.util.Bag;
 
 /**
@@ -24,4 +20,6 @@
 	/** All segments, grouped by cells */
 	Map<Point2D,List<ExtendedSegment>> cellSegments;
+    /** The already detected errors */
+    Bag<Segment, Segment> errorSegments;
 	
 	/**
@@ -31,5 +29,5 @@
 	{
 		super(tr("Crossing roads."),
-			  tr("This test checks if two roads crosses in the same layer, but are not connected by a node."));
+			  tr("This test checks if two roads,railways or waterways crosses in the same layer, but are not connected by a node."));
 	}
 
@@ -39,4 +37,5 @@
 	{
 		cellSegments = new HashMap<Point2D,List<ExtendedSegment>>(1000);
+        errorSegments = new Bag<Segment, Segment>();
 	}
 
@@ -45,4 +44,5 @@
 	{
 		cellSegments = null;
+		errorSegments = null;
 	}
 
@@ -50,9 +50,12 @@
 	public void visit(Way w) 
 	{
-
-        if( w.deleted || w.get("highway") == null)
+        if( w.deleted )
             return;
         
+        if( w.get("highway") == null && w.get("waterway") == null && w.get("railway") == null )
+        	return;
+        
         String layer1 = w.get("layer");
+        String railway1 = w.get("railway");
         for(Segment s : w.segments)
         {
@@ -60,5 +63,5 @@
         		continue;
         	
-            ExtendedSegment es1 = new ExtendedSegment(s, layer1);
+            ExtendedSegment es1 = new ExtendedSegment(s, layer1, railway1);
             List<List<ExtendedSegment>> cellSegments = getSegments(s);
             for( List<ExtendedSegment> segments : cellSegments)
@@ -66,6 +69,11 @@
 	            for( ExtendedSegment es2 : segments)
 	            {
+	            	if( errorSegments.contains(s, es2.s) || errorSegments.contains(es2.s, s))
+	            		continue;
+	            	
 	                String layer2 = es2.layer;
+	                String railway2 = es2.railway;
 	                if( (layer1 == null && layer2 == null || layer1 != null && layer1.equals(layer2)) &&
+	                	!("subway".equals(railway1) && "subway".equals(railway2)) &&	
 	                	es1.intersects(es2))
 	                {
@@ -82,34 +90,59 @@
 	
 	/**
-	 * Returns all the cells this segment crosses . Each cell contains the list
-	 * of segments already processed
-	 * 
-	 * @param s
-	 *            The segment
-	 * @return A list with all the cells the segment crosses.
-	 */
+     * Returns all the cells this segment crosses . Each cell contains the list
+     * of segments already processed
+     * <p>
+     * This method uses the Bresenham algorithm to follow all cells this segment
+     * crosses, so, in very few cases (when the segment is very long, and
+     * crosses a cell very close to the corner), it can miss a cell.
+     * 
+     * @param s The segment
+     * @return A list with all the cells the segment crosses.
+     */
 	public List<List<ExtendedSegment>> getSegments(Segment s)
 	{
 		List<List<ExtendedSegment>> cells = new ArrayList<List<ExtendedSegment>>();
-		long x0 = Math.round(s.from.eastNorth.east()*100);
-		long x1 = Math.round(s.to.eastNorth.east()*100);
-		for( ; x0<=x1; x0++)
-		{
-			long y0 = Math.round(s.from.eastNorth.north()*100);
-			long y1 = Math.round(s.to.eastNorth.north()*100);
-			for( ; y0<=y1; y0++)
-			{
-				Point2D p = new Point2D.Double(x0, y0);
-				List<ExtendedSegment> segments = cellSegments.get( p );
-				if( segments == null )
-				{
-					segments = new ArrayList<ExtendedSegment>();
-					cellSegments.put(p, segments);
-				}
-				
-				cells.add(segments);
-			}
-		}
-		
+		long x0 = Math.round(s.from.eastNorth.east() * 1000);
+		long x1 = Math.round(s.to.eastNorth.east()   * 1000);
+        long y0 = Math.round(s.from.eastNorth.north()* 1000);
+        long y1 = Math.round(s.to.eastNorth.north()  * 1000);
+        
+        boolean steep = Math.abs(y1 - y0) > Math.abs(x1 - x0);
+        long aux;
+        if( steep )
+        {
+            aux = x0; x0 = x1; x1 = aux;
+            aux = y0; y0 = y1; y1 = aux;
+        }
+        if( x0 > x1 )
+        {
+            aux = x0; x0 = x1; x1 = aux;
+            aux = y0; y0 = y1; y1 = aux;
+        }
+        long dx  = x1 - x0,
+             dy  = Math.abs(y1 - y0),
+             y   = y0,
+             error = -dx/2,
+             ystep = y0 < y1 ? 1 : -1;
+      
+        for( long x = x0; x <= x1; x++ )  
+        {
+            Point2D p = steep ? new Point2D.Double(y, x) : new Point2D.Double(x, y);
+            List<ExtendedSegment> segments = cellSegments.get( p );
+            if( segments == null )
+            {
+                segments = new ArrayList<ExtendedSegment>();
+                cellSegments.put(p, segments);
+            }
+            cells.add(segments);
+            
+            error += dy;
+            if( error > 0 )
+            {
+                error -= dx;
+                y += ystep;
+            }
+        }
+        
 		return cells;
 	}
@@ -127,13 +160,18 @@
         String layer;
         
+        /** The railway type */
+		private String railway;
+        
         /**
          * Constructor
          * @param s The segment
          * @param layer The layer of the way this segment is in
+         * @param railway The railway type of the way this segment is in
          */
-        public ExtendedSegment(Segment s, String layer)
+        public ExtendedSegment(Segment s, String layer, String railway)
         {
             this.s = s;
             this.layer = layer;
+            this.railway = railway;
         }