Scoring System Explanation Sprint 3 & Bug Fix Sprint 4

Overview

In sprint 3, team 9 continue doing scoring system. At the end of sprint 2, team 8 had suggested considering distance as another parameter for scores (https://github.com/UQdeco2800/2021-ext-studio-2/issues/99#issuecomment-916604525). Now we add it! The distance value is based on player.getPosition(). The distance related code is in DistanceService.java. We added the distance value to baseScore after the "seconds" in ScoreService.java. We also display this value in DistanceDisplay.java.

This part is related to this feature ticket (https://github.com/UQdeco2800/2021-ext-studio-2/issues/227). Overall, we successfully finished this feature.

However, during the code check after sprint 3, we found two minor errors about the distance values.

1. The initial distance value is not zero
2. The distance value reduces right after player transmit back from the new map (through the tunnel). This issue is related to this feature ticket (https://github.com/UQdeco2800/2021-ext-studio-2/issues/227). Same ticket in sprint 3 but with updates.

Code description

Sprint 4 bug fixed explanation

In sprint 3, we tested if the distance board has some initial values so we initialised distance to 5 but we forgot to change it. So first we set that value to 0.

In order to fix the distance reduction bug, we have to know why it happens. We ran several times and noticed it happens when the player returns from the new map. That is because when Team 8 implement the code for returning and entering the map, they hard coded the player's position in MainGameScreen.java. We collabrate with them and fix it by:

1. Store the player's current position when player enters the tunnel or get out the tunnel.
2. Get the that pre-distance value in the DistanceService.java. Add it to the base distance.

We created two new Java classes and changed several files.

UML - Class digram

*** Sorry about the confusion, the italic font doesn't mean the classes are abstract. I didn't know how to change them in draw.io.

Design Pattern

We used "Observer" pattern. Because once the distance value is changed, the distance display (GUI), the score value, the score display (GUI), team 7 achievments will all be changed together. This is a "one-to-many" dependency between objects.

Explanation of code

Although the DistanceService.java is very short, we still keep it which makes the code clearer. The distance is calculated from the player's x and y position.

public class DistanceService {
    private double distance=5;
    private Entity player;

    public DistanceService(Entity player){
        this.player=player;
    }

    private static Logger logger = LoggerFactory.getLogger(ScoreService.class);

    public double getDistance() {
        Vector2 pos=player.getPosition();
        distance=Math.sqrt(pos.x*pos.x+pos.y*pos.y);
        return distance;
    }

Here is the part of code from ScoreService.java that uses Distance. We added distance into the base score.

    /** give score in seconds
     * also count distance (sprint3)*/
    private int getBaseScore() {
        return (int) (gametime.getTime()/1000 + ServiceLocator.getDistanceService().getDistance());
    }

Here is the part of code from DistanceDisplay.java. This class is similar to ScoreDisplay.java, TimeDisplay.java. They are separate because they were done in different sprints. We used two tables, one for the board.png and one for label, the png table must be added first so the label is at the top of the board.

    /**
     * Creates actors and positions them on the stage using a table.
     *
     * @see Table for positioning options
     */
    private void addActors() {
        //Use two tables to fill the png with the score text
        tableForText = new Table();
        tableForText.bottom().left();
        tableForText.setFillParent(true);
        tableForText.padBottom(40).padLeft(90);

        tableForBoard = new Table();
        tableForBoard.bottom().left();
        tableForBoard.setFillParent(true);
        tableForBoard.padBottom(-35).padLeft(0);

        // Distance Board
        float boardSideLength = 250f;
        distanceBoard = new Image(ServiceLocator.getResourceService()
                .getAsset("images/distanceboard.png", Texture.class));

        // Distance text
        double distance = 0;
        CharSequence distanceText = "" + distance;
        distanceLabel = new Label(distanceText, new Label.LabelStyle(new BitmapFont(), Color.VIOLET));
        distanceLabel.setFontScale(2f);

        tableForBoard.add(distanceBoard).size(boardSideLength);
        tableForText.add(distanceLabel);
        stage.addActor(tableForBoard);
        stage.addActor(tableForText);
    }

    @Override
    public void update() {
        super.update();
        entity.getEvents().trigger("updateDistance",
                ServiceLocator.getDistanceService().getDistance());
    }