Rewrote the traffic history visualization with blue arrows that fade

away based on their age. Age is calculated from the simulation time
so the fade depends on the simulation speed.

tools/cooja/java/se/sics/cooja/plugins/skins/TrafficVisualizerSkin.java

@@ -34,6 +34,7 @@ package se.sics.cooja.plugins.skins;
 import java.awt.Color;
 import java.awt.Graphics;
 import java.awt.Point;
+import java.awt.Polygon;
 import java.util.ArrayDeque;
 import java.util.Observable;
 import java.util.Observer;
@@ -72,25 +73,23 @@ import se.sics.cooja.radiomediums.AbstractRadioMedium;
 @ClassDescription("Radio traffic")
 public class TrafficVisualizerSkin implements VisualizerSkin {
   private static Logger logger = Logger.getLogger(TrafficVisualizerSkin.class);
-
+  
-  private static final boolean DRAW_ARROWS = true;
-  private static final Color COLOR_HISTORY = new Color(100, 100, 100, 100);
-
   private Simulation simulation = null;
   private Visualizer visualizer = null;
 
   private Box counters;
 
-  private final static int HISTORY_SIZE = 16;
+  private final int MAX_HISTORY_SIZE = 200;
-  private boolean showHistory = false;
+  private boolean showHistory = true;
-  private ArrayDeque<RadioConnection> history = new ArrayDeque<RadioConnection>();
+  private ArrayDeque<RadioConnectionArrow> history = new ArrayDeque<RadioConnectionArrow>();
 
   private AbstractRadioMedium radioMedium;
   private Observer radioObserver, radioMediumObserver;
 
-  public void setActive(Simulation simulation, Visualizer vis) {
+  public void setActive(final Simulation simulation, Visualizer vis) {
     if (!(simulation.getRadioMedium() instanceof AbstractRadioMedium)) {
-      logger.fatal("Radio medium type not supported: " + simulation.getRadioMedium());
+      logger.fatal("Radio medium type not supported: "
+          + simulation.getRadioMedium());
       return;
     }
     this.radioMedium = (AbstractRadioMedium) simulation.getRadioMedium();
@@ -99,7 +98,8 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
 
     final JLabel txCounter = new JLabel("TX: " + radioMedium.COUNTER_TX);
     final JLabel rxCounter = new JLabel("RX: " + radioMedium.COUNTER_RX);
-    final JLabel interferedCounter = new JLabel("INT: " + radioMedium.COUNTER_INTERFERED);
+    final JLabel interferedCounter = new JLabel("INT: "
+        + radioMedium.COUNTER_INTERFERED);
 
     counters = Box.createHorizontalBox();
     counters.add(txCounter);
@@ -108,22 +108,19 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
     counters.add(Box.createHorizontalStrut(10));
     counters.add(interferedCounter);
 
- /*   visualizer.getCurrentCanvas().add(counters);*/
+    /* visualizer.getCurrentCanvas().add(counters); */
 
     /* Start observing radio medium and radios */
     radioMedium.addRadioMediumObserver(radioMediumObserver = new Observer() {
       public void update(Observable obs, Object obj) {
         txCounter.setText("TX: " + radioMedium.COUNTER_TX);
         rxCounter.setText("RX: " + radioMedium.COUNTER_RX);
-        interferedCounter.setText("INT: " +  + radioMedium.COUNTER_INTERFERED);
+        interferedCounter.setText("INT: " + +radioMedium.COUNTER_INTERFERED);
 
         if (showHistory) {
           RadioConnection last = radioMedium.getLastConnection();
-          if (last != null) {
+          if (last != null && history.size() < MAX_HISTORY_SIZE) {
-            history.add(last);
+            history.add(new RadioConnectionArrow(last));
-            while (history.size() > HISTORY_SIZE) {
-              history.removeFirst();
-            }
           }
         }
         visualizer.repaint();
@@ -141,6 +138,7 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
           r.addObserver(radioObserver);
         }
       }
+
       public void moteWasRemoved(Mote mote) {
         Radio r = mote.getInterfaces().getRadio();
         if (r != null) {
@@ -149,13 +147,33 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
         history.clear();
       }
     });
-    for (Mote mote: simulation.getMotes()) {
+    for (Mote mote : simulation.getMotes()) {
       Radio r = mote.getInterfaces().getRadio();
       if (r != null) {
         r.addObserver(radioObserver);
       }
     }
 
+    simulation.addMillisecondObserver(new Observer() {
+      public void update(Observable obs, Object obj) {
+        if((simulation.getSimulationTimeMillis() % 100) == 0) {
+          RadioConnectionArrow[] historyArr = history.toArray(new RadioConnectionArrow[0]);
+          if(historyArr.length > 0) {
+            visualizer.repaint();
+          }
+          for (RadioConnectionArrow connArrow : historyArr) {
+            if (connArrow == null) {
+              continue;
+            }
+            connArrow.increaseAge();
+            if(connArrow.getAge() >= connArrow.getMaxAge()) {
+              history.remove(connArrow);            
+            }
+          }
+        }
+        
+      }
+    });
     /* Register menu actions */
     visualizer.registerSimulationMenuAction(ToggleHistoryAction.class);
   }
@@ -170,7 +188,7 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
 
     /* Stop observing radio medium and radios */
     radioMedium.deleteRadioMediumObserver(radioMediumObserver);
-    for (Mote mote: simulation.getMotes()) {
+    for (Mote mote : simulation.getMotes()) {
       Radio r = mote.getInterfaces().getRadio();
       if (r != null) {
         r.addObserver(radioObserver);
@@ -182,35 +200,38 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
   }
 
   public Color[] getColorOf(Mote mote) {
-    if (simulation == null) {
-      /* Skin was never activated */
-      return null;
-    }
-
-    Radio moteRadio = mote.getInterfaces().getRadio();
-    if (moteRadio == null) {
-      return null;
-    }
-
-    if (!moteRadio.isRadioOn()) {
-      return new Color[] { Color.GRAY };
-    }
-
-    if (moteRadio.isTransmitting()) {
-      return new Color[] { Color.BLUE };
-    }
-
-    if (moteRadio.isInterfered()) {
-      return new Color[] { Color.RED };
-    }
-
-    if (moteRadio.isReceiving()) {
-      return new Color[] { Color.GREEN };
-    }
-
     return null;
   }
 
+  private Polygon arrowPoly = new Polygon();
+  private void drawArrow(Graphics g, int xSource, int ySource, int xDest, int yDest, int delta) {
+    double dx = xSource - xDest;
+    double dy = ySource - yDest;
+    double dir = Math.atan2(dx, dy);
+    double len = Math.sqrt(dx * dx + dy * dy);
+    dx /= len;
+    dy /= len;
+    len -= delta;
+    xDest = xSource - (int) (dx * len);
+    yDest = ySource - (int) (dy * len);
+    g.drawLine(xDest, yDest, xSource, ySource);
+
+    final int size = 8;
+    arrowPoly.reset();
+    arrowPoly.addPoint(xDest, yDest);
+    arrowPoly.addPoint(xDest + xCor(size, dir + 0.5), yDest + yCor(size, dir + 0.5));
+    arrowPoly.addPoint(xDest + xCor(size, dir - 0.5), yDest + yCor(size, dir - 0.5));
+    arrowPoly.addPoint(xDest, yDest);
+    g.fillPolygon(arrowPoly);
+  }
+
+  private int yCor(int len, double dir) {
+    return (int)(0.5 + len * Math.cos(dir));
+  }
+
+  private int xCor(int len, double dir) {
+    return (int)(0.5 + len * Math.sin(dir));
+  }
   public void paintBeforeMotes(Graphics g) {
     if (simulation == null) {
       /* Skin was never activated */
@@ -219,18 +240,20 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
 
     if (showHistory) {
       /* Paint history in gray */
-      RadioConnection[] historyArr = history.toArray(new RadioConnection[0]);
+      RadioConnectionArrow[] historyArr = history.toArray(new RadioConnectionArrow[0]);
-      for (RadioConnection conn : historyArr) {
+      for (RadioConnectionArrow connArrow : historyArr) {
-        if (conn == null) {
+        if (connArrow == null) {
           continue;
         }
-        g.setColor(COLOR_HISTORY);
+        float colorHistoryIndex = (float)connArrow.getAge() / (float)connArrow.getMaxAge();
-        Radio source = conn.getSource();
+        g.setColor(new Color(colorHistoryIndex, colorHistoryIndex, 1.0f));
-        Point sourcePoint = visualizer.transformPositionToPixel(source.getPosition());
+        Radio source = connArrow.getConnection().getSource();
-        for (Radio destRadio : conn.getDestinations()) {
+        Point sourcePoint = visualizer.transformPositionToPixel(source
+            .getPosition());
+        for (Radio destRadio : connArrow.getConnection().getDestinations()) {
           Position destPos = destRadio.getPosition();
-          Point destPoint = visualizer.transformPositionToPixel(destPos);
+          Point destPoint = visualizer.transformPositionToPixel(destPos);          
-          g.drawLine(sourcePoint.x, sourcePoint.y, destPoint.x, destPoint.y);
+          drawArrow(g, sourcePoint.x, sourcePoint.y, destPoint.x, destPoint.y, 8);
         }
       }
     }
@@ -244,24 +267,15 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
           continue;
         }
         Radio source = conn.getSource();
-        Point sourcePoint = visualizer.transformPositionToPixel(source.getPosition());
+        Point sourcePoint = visualizer.transformPositionToPixel(source
+            .getPosition());
         for (Radio destRadio : conn.getDestinations()) {
           if (destRadio == null) {
             continue;
           }
           Position destPos = destRadio.getPosition();
           Point destPoint = visualizer.transformPositionToPixel(destPos);
-          g.drawLine(sourcePoint.x, sourcePoint.y, destPoint.x, destPoint.y);
+          drawArrow(g, sourcePoint.x, sourcePoint.y, destPoint.x, destPoint.y, 8);          
-
-          /* Draw arrows */
-          if (DRAW_ARROWS) {
-            Point centerPoint = new Point(
-                destPoint.x/2 + sourcePoint.x/2,
-                destPoint.y/2 + sourcePoint.y/2
-            );
-            int startAngle = (int) (-180 * Math.atan2(destPoint.y - sourcePoint.y, destPoint.x - sourcePoint.x)/Math.PI - 90);
-            g.drawArc(centerPoint.x-5, centerPoint.y-5, 10, 10, startAngle, 180);
-          }
         }
       }
     }
@@ -269,7 +283,7 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
 
   public void paintAfterMotes(Graphics g) {
   }
-  
+
   public static class ToggleHistoryAction implements SimulationMenuAction {
     public boolean isEnabled(Visualizer visualizer, Simulation simulation) {
       return true;
@@ -278,9 +292,9 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
     public String getDescription(Visualizer visualizer, Simulation simulation) {
       VisualizerSkin[] skins = visualizer.getCurrentSkins();
       boolean showing = false;
-      for (VisualizerSkin skin: skins) {
+      for (VisualizerSkin skin : skins) {
         if (skin instanceof TrafficVisualizerSkin) {
-          showing = ((TrafficVisualizerSkin)skin).showHistory;
+          showing = ((TrafficVisualizerSkin) skin).showHistory;
         }
       }
       if (showing) {
@@ -291,9 +305,9 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
 
     public void doAction(Visualizer visualizer, Simulation simulation) {
       VisualizerSkin[] skins = visualizer.getCurrentSkins();
-      for (VisualizerSkin skin: skins) {
+      for (VisualizerSkin skin : skins) {
         if (skin instanceof TrafficVisualizerSkin) {
-          ((TrafficVisualizerSkin)skin).showHistory = !((TrafficVisualizerSkin)skin).showHistory;
+          ((TrafficVisualizerSkin) skin).showHistory = !((TrafficVisualizerSkin) skin).showHistory;
           visualizer.repaint();
         }
       }
@@ -303,4 +317,26 @@ public class TrafficVisualizerSkin implements VisualizerSkin {
   public Visualizer getVisualizer() {
     return visualizer;
   }
+  
+  private class RadioConnectionArrow {
+    private RadioConnection conn;
+    private int age;
+    private final int MAX_AGE = 10;
+    RadioConnectionArrow(RadioConnection conn) {
+      this.conn = conn;
+      this.age = 0;
+    }
+    public void increaseAge() {
+      age++;
+    }
+    public int getAge() {
+      return age;
+    }
+    public RadioConnection getConnection() {
+      return conn;
+    }
+    public int getMaxAge() {
+      return MAX_AGE;
+    }
+  }
 }