private void PrecisionPaddle() {
if (ball.getY()
> HEIGHT
- PADDLE_Y_OFFSET
- PADDLE_HEIGHT
- BALL_RADIUS * 2) { // check if the ball drops below the paddle
double diff = ball.getY() - (HEIGHT - PADDLE_Y_OFFSET - PADDLE_HEIGHT - BALL_RADIUS * 2);
ball.move(0, -2 * diff); // move ball an amount equal to the amount it drops below the paddle
}
}
private void checkForCollision() {
// check if ball has hit floor. If so, bounce it upwards.
if (ball.getY() > getHeight() - DIAM_BALL) {
bounceClip.play();
yVel = -yVel * BOUNCE_REDUCE; // bounces back almost to BOUNCE_REDUCE * starting height
// moves ball back above the floor the same distance it would have dropped below the floor in
// same time
double diff = ball.getY() - (getHeight() - DIAM_BALL);
ball.move(0, -2 * diff);
}
}
private void checkWall() {
boolean checkLeftWall = ball.getX() <= 0;
boolean checkRightWall = ball.getX() + BALL_RADIUS * 2 >= WIDTH;
boolean checkTop = ball.getY() <= 0;
if ((checkLeftWall) || (checkRightWall)) {
vx = -vx;
}
if (checkTop) {
vy = -vy;
}
}
/** Check for collision */
private void checkRebounce() {
// check for left/right/top wall
if (ball.getX() < 0) {
vx *= -1;
ball.move(vx, 0);
return;
} else if ((ball.getX() + 2 * BALL_RADIUS) > getWidth()) {
vx *= -1;
ball.move(vx, 0);
return;
} else if (ball.getY() < 0) {
ball.setLocation(ball.getX(), -ball.getY());
vy *= -1;
return;
}
// check for collision with bricks: from the four vertexs
lefttop = getElementAt(ball.getX(), ball.getY());
righttop = getElementAt(ball.getX() + 2 * BALL_RADIUS, ball.getY());
leftbottom = getElementAt(ball.getX(), ball.getY() + 2 * BALL_RADIUS);
rightbottom = getElementAt(ball.getX() + 2 * BALL_RADIUS, ball.getY() + 2 * BALL_RADIUS);
if ((lefttop != null) && (righttop != null) && (lefttop != board) && (lefttop != mylabel)) {
remove(lefttop);
num_brick_left--;
vy *= -1;
} else if ((righttop != null)
&& (rightbottom != null)
&& (righttop != board)
&& (righttop != mylabel)) {
remove(righttop);
num_brick_left--;
vx *= -1;
} else if ((rightbottom != null)
&& (leftbottom != null)
&& (rightbottom != board)
&& (rightbottom != mylabel)) {
remove(rightbottom);
num_brick_left--;
vy *= -1;
} else if ((leftbottom != null)
&& (lefttop != null)
&& (leftbottom != board)
&& (leftbottom != mylabel)) {
remove(leftbottom);
num_brick_left--;
vx *= -1;
}
// check for collision with board
if (getElementAt(ball.getX(), (ball.getY() + BALL_RADIUS / 2)) == board) {
vy *= -1;
ball.move(0, vy);
}
}
private void checkObject() {
// x and y parameters for the different corners
double leftX = ball.getX();
double rightX = ball.getX() + (2 * BALL_RADIUS);
double upperY = ball.getY();
double lowerY = ball.getY() + (2 * BALL_RADIUS);
// check the corners for object
GObject upperLeft = checkCorner(leftX, upperY); // check upper-left corner
if (upperLeft == null) {
GObject upperRight = checkCorner(rightX, upperY); // check upper-right corner
}
GObject lowerLeft = checkCorner(leftX, lowerY); // //check lower-left corner
if (lowerLeft == null) {
GObject lowerRight = checkCorner(rightX, lowerY); // check lower-right corner
if ((lowerLeft == paddle)
&& (lowerRight == paddle)) { // When both lower corners hit paddle, change direction.
vy = -vy;
}
}
}
private void gaming() {
boolean loseOneTurn;
boolean win = false;
boolean stillAlive = true;
for (int i = NTURNS; i > 0; i--) { // loops for the number of turns.
GLabel life = showLifeCount(i);
waitForClick();
add(life);
while (stillAlive) { // the ball moves and bounces until the user loses or wins the turn.
moveBall();
loseOneTurn =
(ball.getY() >= HEIGHT); // user loses one turn when the ball falls under the paddle.
win = (brickCount == 0); // user wins when there is no brick left.
stillAlive = !(loseOneTurn || win);
}
if (win) break; // breaks from the loop if the user wins in one turn.
remove(ball);
createBall(); // a new ball appears on the center of the screen after one turn
stillAlive = true;
remove(life);
}
}
/** Check whether the game is over */
private boolean gameover() {
return (ball.getY() > (getHeight() - 2 * BALL_RADIUS)) || (num_brick_left == 0);
}