Question

Okay, I’ve got this game loop which never terminates —

public void run() {
    setup();
    addMouseListeners();
    int Turns = NTURNS;
    int TotalBricks = NBRICKS_PER_ROW * NBRICK_ROWS;
    while ((Turns>0) && (TotalBricks>0)) {
        moveBall();
        checkForCollision();
        pause(DELAY);
    }
    System.exit(0);
}   

— even though I have this method decrementing the Turns value every time the ball is missed:

private void checkForCollision() {
    GObject collider = getCollidingObject();
    if (collider !=null) {
        if (collider == Paddle) {
            vy= -vy;
        }
        else {
            vy= -vy;
            remove(collider);
            TotalBricks = TotalBricks - 1;
        }
    }
    if((ball.getX()>=(WIDTH-BALL_RADIUS)) || (ball.getX()<=0)) {
        vx = -vx;
    }
    if(ball.getY()<=0) {
        vy = -vy;
    }
    if(ball.getY()>=HEIGHT) {
    Turns = Turns -1;
    remove(ball);
    newBall();
    }

}

plus this

private int Turns;

at the bottom to ensure that the variable is shared among both methods.
No matter how many times the ball is missed, the game never stops.
What am I missing?
Thx

Answer 1

You’re declaring your Turns variable twice, once for the entire class and once for the the run() method. Since you are also checking the value of the Turns variable that you’ve declared in the run() method, it never decreases because the one being used in checkForCollision() isn’t the one that’s being checked in the while loop.

In run(), this:

int Turns = NTURNS;

needs to be:

Turns = NTURNS;