/** 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);
}
}
public void run() {
GOval o = new GOval(40, 40);
o.setColor(Color.RED);
o.setFilled(true);
add(o, 100, 100);
while (true) {
pause(WAIT);
o.move(xMove, yMove);
}
}
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);
}
}
/**
* The method which controls the movement the ball, check all the objects with which the ball is
* faced and performs the appropriate actions to them
*/
private boolean runBall() {
double vx;
double vy = SPEED_Y;
boolean res = false;
vx = rgen.nextDouble(1.0, 3.0); // randomly sets horizontal speed
if (rgen.nextBoolean(
0.5)) // with a 50 percent chance change the direction of movement of the ball
vx = -vx;
while (allDelBricks
< NBRICK_ROWS * NBRICKS_PER_ROW) { // The game will not end until all the bricks
GObject collider = getCollidingObject(); // The variable gets test result object
vx = checkTheLeftAndRightWall(vx); // Check the collision of the ball on the side walls
vy =
checkTheTopWallAndPaddle(vy); // Check the collision of the ball on the ceiling and paddle
vx =
checkLeftAndRightWallOfPaddle(
vx); // Check the collision of the ball with the side part of the paddle
if (collider != null) { // If checkpoints are returned brick, it is then removed
if (collider != paddle) {
remove(collider);
vy = -vy;
allDelBricks++;
}
}
ball.move(vx, vy);
pause(TIME_PAUSE);
if (ball.getY()
> HEIGHT
- (PADDLE_Y_OFFSET / 3)
- BALL_RADIUS * 2) { // The game stops when the ball falls below the window
res = false;
return res;
}
res = true;
}
return res;
}
// Update/move ball down and sideways. yVel increases each cycle, due to gravity.
private void moveBall() {
yVel += GRAVITY;
ball.move(xVel, yVel);
}
private void startFall() {
ball.move(vx, vy);
pause(DELAY);
ball.sendToBack();
}
/** Move the ball */
private void moveBall() {
ball.move(vx, vy);
}