Implemented wake visualisation for each boat

- Added and tested wake calculation for BoatInRace
- Draws boat in canvas between start and entering Finish leg
- Allow boat velocity to be set after initialisation for testing
#story [21]

src/main/java/seng302/Controllers/RaceController.java

@@ -66,6 +66,7 @@ public class RaceController extends Controller{
         BoatInRace[] boatInRaces = new BoatInRace[boats.size()];
         raceMap.setBoats(boats.toArray(boatInRaces));
         raceMap.drawRaceMap();
+        raceMap.updateBoats();
     }
 
     /**

src/main/java/seng302/Model/Boat.java

@@ -48,6 +48,10 @@ public class Boat {
         return velocity;
     }
 
+    public void setVelocity(double velocity) {
+        this.velocity = velocity;
+    }
+
     /**
      *
      * @return The Name of the boat.

src/main/java/seng302/Model/BoatInRace.java

@@ -6,6 +6,7 @@ import javafx.scene.paint.Color;
 import org.geotools.referencing.GeodeticCalculator;
 import seng302.GPSCoordinate;
 
+import java.awt.geom.Point2D;
 
 
 /**
@@ -147,7 +148,7 @@ public class BoatInRace extends Boat {
 
     /**
      * Converts an azimuth to a bearing
-     * @param azimuth azimuth valuye to be converted
+     * @param azimuth azimuth value to be converted
      * @return the bearings in degrees (0 to 360).
      */
     public static double calculateHeading(double azimuth) {
@@ -167,4 +168,17 @@ public class BoatInRace extends Boat {
         double azimuth = this.calculateAzimuth();
         return calculateHeading(azimuth);
     }
+
+    public GPSCoordinate getWake() {
+        double reverseHeading = calculateHeading() - 180;
+        double distance = getVelocity();
+
+        GeodeticCalculator calc = new GeodeticCalculator();
+        calc.setStartingGeographicPoint(
+                new Point2D.Double(getCurrentPosition().getLongitude(), getCurrentPosition().getLatitude())
+        );
+        calc.setDirection(reverseHeading, distance);
+        Point2D endpoint = calc.getDestinationGeographicPoint();
+        return new GPSCoordinate(endpoint.getY(), endpoint.getX());
+    }
 }

src/main/java/seng302/Model/ResizableRaceCanvas.java

@@ -66,8 +66,9 @@ public class ResizableRaceCanvas extends Canvas {
      * @see Paint
      */
     public void displayMark(GraphCoordinate graphCoordinate, Paint paint){
+        double d = 15;
         gc.setFill(paint);
-        gc.fillOval(graphCoordinate.getX(), graphCoordinate.getY(), 15, 15);
+        gc.fillOval(graphCoordinate.getX() - (d/2), graphCoordinate.getY() - (d/2), d, d);
     }
 
     /**
@@ -187,7 +188,6 @@ public class ResizableRaceCanvas extends Canvas {
         if (boats != null) {
             for (BoatInRace boat : boats) {
                 if (boat != null) {
-//                    System.out.print("Drawing Boat At: " + boat.getCurrentPosition());
                     displayMark(this.map.convertGPS(boat.getCurrentPosition()), boat.getColour());
                     displayText(boat.getAbbrev(), boat.getVelocity(), this.map.convertGPS(boat.getCurrentPosition()));
                 }
@@ -198,17 +198,16 @@ public class ResizableRaceCanvas extends Canvas {
         displayArrow(new GraphCoordinate(500, 20), 100);
     }
 
-    /**
-     * Draws a boat at a certain GPSCoordinate
-     * @param colour Colour to colour boat.
-     * @param gpsCoordinates GPScoordinate that the boat is to be drawn at.
-     * @see GPSCoordinate
-     * @see Color
-     */
-    public void drawBoat(Color colour, GPSCoordinate gpsCoordinates) {
-        GraphCoordinate graphCoordinate =  this.map.convertGPS(gpsCoordinates);
-        //System.out.println("DrawingBoat" + gpsCoordinates.getLongitude());
-        displayPoint(graphCoordinate, colour);
+    public void updateBoats() {
+        if (boats != null) {
+            for (BoatInRace boat : boats) {
+                if (boat != null && !boat.getCurrentLeg().getName().equals("Finish")) {
+                    GraphCoordinate wakeFrom = this.map.convertGPS(boat.getCurrentPosition());
+                    GraphCoordinate wakeTo = this.map.convertGPS(boat.getWake());
+                    displayLine(wakeFrom, wakeTo, boat.getColour());
+                }
+            }
+        }
     }
 
     /**

src/test/java/seng302/Model/BoatInRaceTest.java

@@ -1,6 +1,7 @@
 package seng302.Model;
 
 import javafx.scene.paint.Color;
+import org.junit.Assert;
 import org.junit.Ignore;
 import org.junit.Test;
 import seng302.GPSCoordinate;
@@ -111,4 +112,43 @@ public class BoatInRaceTest {
         assertEquals(testBoat.getVelocity(), 20.0);
     }
 
+
+    @Test
+    public void getWakeAtProperHeading() throws Exception {
+        BoatInRace boat = new BoatInRace("Test", 1, Color.ALICEBLUE, "tt");
+
+        // Construct leg of 0 degrees
+        GPSCoordinate startPoint = new GPSCoordinate(0, 0);
+        GPSCoordinate endPoint = new GPSCoordinate(50, 0);
+        Leg leg0deg = new Leg("Start", startPoint, endPoint, 0);
+        boat.setCurrentLeg(leg0deg);
+        boat.setCurrentPosition(new GPSCoordinate(0,0));
+
+        assertEquals(0, boat.calculateHeading(), 1e-8);
+
+        // Construct leg from wake - heading should be 180 degrees
+        Leg leg180deg = new Leg("Start", startPoint, boat.getWake(), 0);
+        boat.setCurrentLeg(leg180deg);
+
+        assertEquals(180, boat.calculateHeading(), 1e-8);
+    }
+
+    @Test
+    public void getWakeProportionalToVelocity() throws Exception {
+        BoatInRace boat = new BoatInRace("Test", 10, Color.ALICEBLUE, "tt");
+
+        // Construct leg of 0 degrees at 0 N
+        GPSCoordinate startPoint = new GPSCoordinate(0, 0);
+        GPSCoordinate endPoint = new GPSCoordinate(50, 0);
+        Leg leg0deg = new Leg("Start", startPoint, endPoint, 0);
+        boat.setCurrentLeg(leg0deg);
+        boat.setCurrentPosition(new GPSCoordinate(0,0));
+
+        // Get latitude of endpoint of wake at 10 kn (longitude is 0)
+        double endpointAt10Kn = boat.getWake().getLatitude();
+
+        // Latitude of endpoint at 20 kn should be twice endpoint at 10 kn
+        boat.setVelocity(20);
+        assertEquals(2*endpointAt10Kn, boat.getWake().getLatitude(), 1e-8);
+    }
 }