Boats now reverse smoothly when colliding

- Collision objects specify which boat is colliding
- RaceLogic sets up an observable CollisionCommand when collision bubbles up
- Boats now selectively identify observers of collision

#story[1196]

racevisionGame/src/main/java/mock/model/RaceLogic.java

@@ -2,6 +2,7 @@ package mock.model;
 
 import javafx.animation.AnimationTimer;
 import mock.model.collider.Collision;
+import mock.model.commandFactory.CollisionCommand;
 import mock.model.commandFactory.Command;
 import mock.model.commandFactory.CompositeCommand;
 import mock.model.commandFactory.CommandFactory;
@@ -222,11 +223,9 @@ public class RaceLogic implements RunnableWithFramePeriod, Observer {
 
     @Override
     public void update(Observable o, Object arg) {
-        Collision e = (Collision)arg;
-
-//        if(e.getBearing().degrees() == 0) System.out.println("Ahead");
-//        else if(e.getBearing().degrees() < 90) System.out.println("Starboard");
-//        else if(e.getBearing().degrees() > 270) System.out.println("Port");
-//        else System.out.println("Behind");
+        if(arg instanceof Collision) {
+            Collision collision = (Collision)arg;
+            commands.addCommand(new CollisionCommand(race, (MockBoat)collision.getBoat()));
+        }
     }
 }

racevisionGame/src/main/java/mock/model/collider/Collider.java

@@ -25,13 +25,9 @@ public abstract class Collider extends Observable implements Locatable {
         Bearing relative = Bearing.fromDegrees(absolute.degrees() - boat.getBearing().degrees());
 
         if(actualDistance <= distance) {
-            Collision collision = new Collision(relative, distance);
+            Collision collision = new Collision(boat, relative, distance);
             // Notify object of collision
-            onCollisionEnter(boat, collision);
-            // Notify observers of collision
-            notifyObservers(collision);
-            this.setChanged();
-
+            onCollisionEnter(collision);
             return true;
         } else return false;
     }
@@ -45,8 +41,7 @@ public abstract class Collider extends Observable implements Locatable {
 
     /**
      * Handle a collision event
-     * @param collider Boat that is colliding
      * @param e details of collision
      */
-    public abstract void onCollisionEnter(Boat collider, Collision e);
+    public abstract void onCollisionEnter(Collision e);
 }

racevisionGame/src/main/java/mock/model/collider/ColliderRegistry.java

@@ -1,5 +1,6 @@
 package mock.model.collider;
 
+import mock.model.MockBoat;
 import shared.model.Boat;
 import shared.model.GPSCoordinate;
 
@@ -39,7 +40,7 @@ public class ColliderRegistry extends Collider implements Observer {
     }
 
     @Override
-    public void onCollisionEnter(Boat collider, Collision e) {}
+    public void onCollisionEnter(Collision e) {}
 
     @Override
     public GPSCoordinate getPosition() {
@@ -60,7 +61,7 @@ public class ColliderRegistry extends Collider implements Observer {
     public void update(Observable o, Object arg) {
         Collision collision = (Collision)arg;
 
-        notifyObservers(collision);
         this.setChanged();
+        notifyObservers(collision);
     }
 }

racevisionGame/src/main/java/mock/model/collider/Collision.java

@@ -1,6 +1,7 @@
 package mock.model.collider;
 
 import shared.model.Bearing;
+import shared.model.Boat;
 
 /**
  * Data structure for holding collision details for ray casting and event handling.
@@ -14,13 +15,19 @@ public class Collision {
      * Distance from boat centre to target centre
      */
     private double distance;
+    /**
+     * Boat involved in the collision
+     */
+    private Boat boat;
 
     /**
      * Constructor for Collision structure
+     * @param boat involved in collision
      * @param bearing from boat heading to target
      * @param distance from boat centre to target centre
      */
-    public Collision(Bearing bearing, double distance) {
+    public Collision(Boat boat, Bearing bearing, double distance) {
+        this.boat = boat;
         this.bearing = bearing;
         this.distance = distance;
     }
@@ -32,4 +39,8 @@ public class Collision {
     public double getDistance() {
         return distance;
     }
+
+    public Boat getBoat() {
+        return boat;
+    }
 }

racevisionGame/src/main/java/mock/model/commandFactory/CollisionCommand.java

@@ -0,0 +1,39 @@
+package mock.model.commandFactory;
+
+import mock.model.MockBoat;
+import mock.model.MockRace;
+import shared.model.Azimuth;
+import shared.model.GPSCoordinate;
+
+import java.util.Observable;
+
+/**
+ * Created by cbt24 on 7/09/17.
+ */
+public class CollisionCommand extends ObserverCommand {
+    private GPSCoordinate startingPosition;
+    private Azimuth azimuth;
+    private double distance;
+
+    public CollisionCommand(MockRace race, MockBoat boat) {
+        super(race, boat);
+    }
+
+    @Override
+    public void execute() {
+        this.azimuth = Azimuth.fromDegrees(boat.getBearing().degrees() - 180d);
+        this.startingPosition = boat.getPosition();
+        this.distance = 30;
+        boat.setVelocityDefault(false);
+    }
+
+    @Override
+    public void update(Observable o, Object arg) {
+        if(GPSCoordinate.calculateDistanceMeters(boat.getPosition(), startingPosition) < distance) {
+            boat.setPosition(GPSCoordinate.calculateNewPosition(boat.getPosition(), 2, azimuth));
+        } else {
+            race.deleteObserver(this);
+            boat.setVelocityDefault(true);
+        }
+    }
+}