Documented methods added for track handling.

#story[758]

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

@@ -258,6 +258,12 @@ public class BoatInRace extends Boat {
         this.position.set(Integer.toString(position + 1));
     }
 
+    /**
+     * Adds a new point to boat's track.
+     * @param coordinate of point on track
+     * @return whether add is successful
+     * @see seng302.Model.TrackPoint
+     */
     public boolean addTrackPoint(GPSCoordinate coordinate) {
         Boolean added = System.currentTimeMillis() >= nextValidTime;
         long currentTime = System.currentTimeMillis();
@@ -268,14 +274,27 @@ public class BoatInRace extends Boat {
         return added;
     }
 
+    /**
+     * Returns the boat's sampled track between start of race and current time.
+     * @return queue of track points
+     * @see seng302.Model.TrackPoint
+     */
     public Queue<TrackPoint> getTrack() {
         return track;
     }
 
+    /**
+     * Returns whether track is visible
+     * @return true if visible
+     */
     public boolean isTrackVisible() {
         return trackVisible;
     }
 
+    /**
+     * Sets track visibility.
+     * @param trackVisible visible if true.
+     */
     public void setTrackVisible(boolean trackVisible) {
         this.trackVisible = trackVisible;
     }

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

@@ -285,12 +285,17 @@ public class ResizableRaceCanvas extends Canvas {
                 if (raceAnno)
                     displayText(boat.getAbbrev(), boat.getVelocity(), this.map.convertGPS(boat.getCurrentPosition()));
 
-                if(boat.isTrackVisible()) drawTrackPoint(boat);
+                if(boat.isTrackVisible()) drawTrack(boat);
             }
         }
     }
 
-    private void drawTrackPoint(BoatInRace boat) {
+    /**
+     * Draws all track points for a given boat. Colour is set by boat, opacity by track point.
+     * @param boat whose track is displayed
+     * @see seng302.Model.TrackPoint
+     */
+    private void drawTrack(BoatInRace boat) {
         for (TrackPoint point : boat.getTrack()) {
             GraphCoordinate scaledCoordinate = this.map.convertGPS(point.getCoordinate());
             Color boatColour = boat.getColour();

src/main/java/seng302/Model/TrackPoint.java

@@ -11,6 +11,12 @@ public class TrackPoint {
     private long expiry;
     private double minAlpha;
 
+    /**
+     * Creates a new track point with fixed GPS coordinates and time, to reach minimum opacity on expiry.
+     * @param coordinate position of point on physical race map
+     * @param timeAdded system clock at time of addition
+     * @param expiry time to minimum opacity after added
+     */
     public TrackPoint(GPSCoordinate coordinate, long timeAdded, long expiry) {
         this.coordinate = coordinate;
         this.timeAdded = timeAdded;
@@ -18,14 +24,26 @@ public class TrackPoint {
         this.minAlpha = 0.1;
     }
 
+    /**
+     * Gets the position of the point on physical race map.
+     * @return GPS coordinate of point
+     */
     public GPSCoordinate getCoordinate() {
         return coordinate;
     }
 
+    /**
+     * Gets opacity of point scaled by age in proportion to expiry, between 1 and minimum opacity inclusive.
+     * @return greater of minimum opacity and scaled opacity
+     */
     public double getAlpha() {
         return Double.max(minAlpha,1.0 - (double)(System.currentTimeMillis() - timeAdded) / expiry);
     }
 
+    /**
+     * Gets time point was added to track.
+     * @return system clock at time of addition
+     */
     public long getTimeAdded() {
         return timeAdded;
     }