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How to make object dissapear when hit

I was working on a brick breaker game in proccessing, and was trying to create the collision system for the game. I was able to identify when a collision happens between the ball and the brick, but I was not able to to make the brick dissapear when it gets hit by the ball. How do I do this? I would also appreciate a explanation, as I am a beginner.
Thanks.
color black = color(0,0,0);
color red = color(255,0,0);
color white = color(255,255,255);
float ballx = 412.5, bally = 600, balld = 20, ballr = balld/2, paddleX = 362.5, paddleY = 650;
float paddleW = 100, paddleH = 15;
float ballspdX, ballspdY;
boolean ball_drop = true;
float direction_choice;
float[] brickX = new float[10];
float[] brickY = new float[5];
float brickW = 50, brickH = 25;
void setup(){
size(825,800);
surface.setTitle("Brick breaker");
noCursor();
smooth();
brickX[0] = 50;
brickX[1] = 125;
brickX[2] = 200;
brickX[3] = 275;
brickX[4] = 350;
brickX[5] = 425;
brickX[6] = 500;
brickX[7] = 575;
brickX[8] = 650;
brickX[9] = 725;
brickY[0] = 50;
brickY[1] = 125;
brickY[2] = 200;
brickY[3] = 275;
brickY[4] = 350;
}
void paddle(){
noStroke();
fill(white);
rect(paddleX, paddleY, paddleW, paddleH);
}
void ball(){
noStroke();
fill(red);
circle(ballx, bally, balld);
}
void draw(){
background(black);
paddle();
ball();
if (bally + ballr == paddleY && ballx > paddleX && ballx < paddleX + (paddleW / 2)){
ball_drop = false;
ballspdY = -ballspdY;
ballspdX = -4;
}
/*
if (bally + ballr == paddleY && ballx > paddleX && ballx < paddleX + paddleW){
ball_drop = false;
ballspdY = -ballspdY;
direction_choice = int(random(1,3));
if (direction_choice == 1){
ballspdX = 4;
}
if (direction_choice == 2){
ballspdX = -4;
}
}
println(direction_choice);
*/
if (bally + ballr == paddleY && ballx > paddleX + (paddleW /2) && ballx < paddleX + paddleW){
ball_drop = false;
ballspdY = -ballspdY;
ballspdX = 4;
}
if (ballx + ballr > width || ballx - ballr < 0){
ballspdX = -ballspdX;
}
if (bally - ballr < 0){
ballspdY = -ballspdY;
}
if (ball_drop){
ballspdX = 0;
ballspdY = 1;
}
for (int i = 0; i < brickX.length; i ++){
for(int j = 0; j < brickY.length; j ++){
fill(red);
rect(brickX[i], brickY[j], brickW, brickH);
if (collideLineCircle(brickX[i], brickY[j] + brickH, brickX[i] + brickW, brickY[j] + brickH, ballx, bally, ballr)){
ballspdY = -ballspdY;
}
}
}
if (bally >= 800){
bally = 600;
ballx = 412.5;
ball_drop = true;
}
bally += ballspdY;
ballx += ballspdX;
}
boolean collideLineCircle(float x1, float y1, float x2, float y2, float cx, float cy, float cr){
float A = y2 - y1, B = x1 - x2, C = x2*y1 - x1+y2;
float denom = A+A + B*B;
if (denom == 0){
return dist(x1,y1, cx, cy) < cr;
}
float Ix = (B*B*cx-A*B*cy - A*C)/denom, Iy = (A*A*cy-A*B*cx - B*C)/denom;
if (Ix >= min(x1,x2) && Ix <= max(x1,x2) & Iy >= min(y1,y2) && Iy <= max(y1,y2)) {
return abs (A*cx + B*cy + C)/sqrt(denom) < cr;
}
float d1 = dist(x1,y1,cx,cy), d2 = dist(x2,y2,cx,cy);
return min(d1,d2) < cr;
}
void mouseMoved(MouseEvent evt){
paddleX = evt.getX();
}

There are a number of ways this can be done. Perhaps the simplest change, given the data structures you already have is to create another array, this time a boolean array, and call it something like brickIsVisible.
Then you can use a simple if statement, e.g., if (brickIsVisible[i]) in your loops to determine how to color the brick. The same variable can be used to tell whether or not to do a collision test between the ball and the brick.
As for the coloring itself, there are a couple options.
I'm not sure how you are drawing your board. If you redraw the entire board with each gameloop frame, then presumably you first draw the background (which covers over the bricks) and then you draw the bricks. If this what is happening, then if brickIsVisible[i] is false you can simply omit drawing that brick on top of the background.
Another technique that is sometimes used is to make use of a transparent color. This is done by adding an alpha channel value to the color definition. Thus there are four variables instead of three. They are referred to as RGBA instead of RGB. If the fourth variable is 0, the color will be transparent. If it is 255 it will be fully visible. Intermediate values in sequence can be used if you want to create a fade in or fade out.
I am guessing you are using java.awt.Color. Following is an example that uses the four argument constructor, with the fourth being the alpha channel.
Color invisiblePurple = new Color(255, 0, 255, 0);
If the color is invisible, the RGB values don't really matter.
These days I mostly use JavaFX for graphics, so I might not be up on all the tricks of the trade with AWT/Swing. With JavaFX, one can directly set an opacity property for a graphic being displayed, which is pretty convenient. I think part of the reason that this is available in JavaFX is that screen graphics are structured more like a DOM tree (like an HTML domain object model), and the redrawing is handled behind the scenes on the current state of the tree, rather than explicitly for each object, as it is with AWT/Swing.

Another possible technique shown below uses a brick class array. The class has a 'show' boolean associated with it and the bricks are only displayed when brick[id].show is true. In this demo when the brick is selected with a mouse brick[id].show is set to false and that brick is not displayed. For your project you would have to do this when a brick is hit by the ball.
/*
Creates a grid of rectangles from a Brick class array.
Syntax: brick[id] = new Brick( x, y, w, h, "title", bkgrndColor, txtColor);
ID is taken from position in array.
*/
final int _brickGridX = 40;
final int _brickGridY = 60;
final int _brickW = 120;
final int _brickH = 60;
color BLUE = color(64, 124, 188);
color LTGRAY = color(185, 180, 180);
color YELLOW = color(245, 250, 13);
color RED = color(255, 0, 0);
color BLACK = color(0, 0, 0);
color WHITE = color(255, 255, 255);
Brick[] brick;
class Brick {
float x, y, w, h;
String title;
color bkgrnd;
color txtColor;
boolean show;
// Constructor
Brick(int xpos, int ypos, float wt, float ht, String titleStr, color background, color foreground) {
x = xpos;
y = ypos;
w = wt;
h = ht;
title = titleStr;
bkgrnd = background;
txtColor = foreground;
}
void display(int id) {
if (brick[id].show) {
fill(bkgrnd); // background color
stroke(0);
rect(x, y, w, h);
fill(txtColor); // text color
textSize(42);
textAlign(CENTER, CENTER);
text(title, x, y, w, h);
}
}
void press(int id) {
println("brick id = ", id + ": show =", brick[id].show);
}
}
void brickGrid() {
int left = 0;
int top = 0;
int vg = 0; // Space between cols (vert.gutter)
int hg = 0; // Space between rows (horz.gutter)
int rows = 5;
int cols = 5;
int id = 0;
brick = new Brick[rows*cols]; // creates brick array
for (int k = 0; k < cols; k++) {
for (int j = 0; j < rows; j++) {
left = _brickGridX + j * (_brickW + vg);
top = _brickGridY + k * (_brickH + hg);
brick[id] = new Brick(left, top, _brickW, _brickH, str(id), LTGRAY, BLACK);
brick[id].show = true;
id++;
}
}
}
void setup() {
size(800, 600);
background(BLUE);
brickGrid();
}
void draw() {
background(BLUE);
for (int i = 0; i < brick.length; i++) {
brick[i].display(i);
}
}
void mousePressed() {
for (int i = 0; i < brick.length; i++) {
if ((mouseX >= brick[i].x) && (mouseX <= brick[i].x + _brickW) && (mouseY >= brick[i].y) && (mouseY <= brick[i].y + _brickH)) {
brick[i].show = false;
// brick[i].press(i);
}
}
}

How to display text inside a moving object in java/processing

I'm using the Processing IDE and I found out how to display static text but not one that displays inside and moves with the moving disk. Any help?
int xdirection = 1; // Left or Right
int ydirection = 1; // Top to Bottom
int value = 0;
Disk disk1;
Disk disk2;
Disk disk3;
Disk disk4;
void setup() {
size(400, 400);
cursor(CROSS);
noStroke();
disk1 = new Disk(color(255, 0, 0), 10, 100, 2, 6);
disk2 = new Disk(color(0, 0, 255), 10, 100, 1, 5);
disk3 = new Disk(color(0, 255, 0), 10, 100, 3, 4);
disk4 = new Disk(color(0, 255, 255), 10, 100, 4, 7);
frameRate(60);
}
void mousePressed() {
if (disk1.isOver() == true) {
value += 25;
}
if (disk2.isOver() == true) {
value += 50;
}
if (disk3.isOver() == true) {
value += 75;
}
if (disk4.isOver() == true) {
value += 100;
}
}
void draw() {
background(130, 140, 255);
stroke(175);
fill(0);
textAlign(CENTER);
text("Score: " + value, width/2, 60);
disk1.bounce();
disk1.display();
disk2.bounce();
disk2.display();
disk3.bounce();
disk3.display();
disk4.bounce();
disk4.display();
}
class Disk {
color c;
float xpos;
float ypos;
float xspeed;
float yspeed;
Disk(color tempC, float tempXpos, float tempYpos, float tempXspeed, float tempYspeed) {
c = tempC;
xspeed = tempXspeed;
yspeed = tempYspeed;
if (xpos > width-200 || xpos < 0) {
xdirection *= -1;
}
if (ypos > height-200 || ypos < 0) {
ydirection *= -1;
}
}
void display() {
stroke(0);
fill(c);
ellipseMode(CENTER);
ellipse(xpos, ypos, 20, 20);
}
boolean isOver() {
// Is mouse position over the circle i.e. dist < radius
if (dist(xpos, ypos, mouseX, mouseY) < 10)
return true;
else
return false;
}
void bounce() {
xpos = xpos + xspeed;
xpos = xpos + ( xspeed * xdirection );
ypos = ypos + ( yspeed * ydirection );
if (xpos > width - 20) {
xspeed = xspeed * -1;
}
if (xpos < 0) {
xspeed = xspeed * -1;
}
if (ypos > height - 20) {
yspeed = yspeed * -1;
}
if (ypos < 0) {
yspeed = yspeed * -1;
}
}
}
Edit: Updated post to show code. I'm also trying to figure out how to make the disks larger using scale() but haven't been able to find out how to do so. This is also my first time posting on stack overflow so if there is anything I can do better, please let me know. Thanks

The Disk class encapsulates the state of a single Disk instance. It contains code for checking mouse clicks and for bouncing. It also contains code for drawing a disk.
That code happens in the display() function. Read through that function to understand what it's doing, and try changing it to see what happens.
Specifically, this line of code draws a circle at the disk's location:
ellipse(xpos, ypos, 20, 20);
Try changing that do draw a rectangle at the disk's location. Then try changing it to draw some text at the disk's location.
Good luck!

Pixels not drawing in java applet

I wrote this program that is supposed to draw a Sierpinski triangle, however whenever I open it with appletviewer on a lower-end computer it will usually draw anywhere from 4 to 60 dots. If I re-open it without re-compiling it the number of dots will occasionally go up from the usual 4. Running it on my higher-end computer at home it works best at around 5 000 000 iterations. However, although it draws the shape fairly full, it starts to draw dots where it should not be possible for there to be dots. This only occurs when the numbers start to get higher. Why is my applet not working on lower end computers, and why does it draw pixels in the incorrect positions at greater values? Here is the code:
import java.applet.Applet;
import java.awt.*;
import java.util.Random;
public class Triangle extends Applet implements Runnable {
Thread runner;
Random rand = new Random();
int xCord, yCord;
double lastX, lastY, currentX, currentY;
final double topX = 500, topY = 100, leftX = 200, leftY = 700,
rightX = 800, rightY = 700;
public void start() {
if (runner == null)
{
runner = new Thread(this);
runner.start();
}
}
public void init() {
lastX = 500; //Top dot
lastY = 100;
}
public void run() {
for(int counter = 1; counter <= 5000000; counter++) {
int n = rand.nextInt(3) + 1;
if (n == 1) { //Top dot
currentX = topX + (lastX - topX) / 2;
currentY = topY + (lastY - topY) / 2;
lastX = currentX;
lastY = currentY;
xCord = (int)Math.round(currentX);
yCord = (int)Math.round(currentY);
repaint();
} else if (n == 2) { //Left dot
currentX = leftX + (lastX - leftX) / 2;
currentY = leftY + (lastY - leftY) / 2;
lastX = currentX;
lastY = currentY;
xCord = (int)Math.round(currentX);
yCord = (int)Math.round(currentY);
repaint();
} else { //Right dot
currentX = rightX + (lastX - rightX) / 2;
currentY = rightY + (lastY - rightY) / 2;
lastX = currentX;
lastY = currentY;
xCord = (int)Math.round(currentX);
yCord = (int)Math.round(currentY);
repaint();
}
}
}
public void update(Graphics g) {
paint(g);
}
public void paint(Graphics g) {
g.fillRect(500, 100, 2, 2); //Top dot, dot 1
g.fillRect(200, 700, 2, 2); //Bottom left dot, dot 2
g.fillRect(800, 700, 2, 2); //Bottom right dot, dot 3
g.fillRect(xCord, yCord, 2, 2);
}
}
Here is my HTML file:
<html>
<body>
<applet code = "Triangle.class" width=999 height=799>
</applet>
</body>
</html>

Need help adding a class and animations to a simple pet drawing?

float x = 100;
float y = 100;
float p = 150;
float l = 10;
float a = 100;
float b = 100;
float n =20;
int value = 255;
int r = 150;
int t = 100;
int s = 100;
int w = 60;
int h = 60;
int z = 11;
int eyeSize = 10;
int pigNose = 30;
int pigBody = 30;
int pigEars = 35;
int pigTail = 20;
int otherpigTail = 200;
int speed = 1;
void setup () {
size (600, 600);
a = width/2.5;
b = height/2;
}
void draw() {
background(184, 233, 249);
//Draw legs
stroke(0);
fill(249, 137, 244);
rect(x+(2*w), y+h/3.5, z, 2*z);
rect(x+(w), y+h/3, z, 2*z);
rect(x+(1.5*w), y+h/3, z, 2*z);
rect(x+(2.5*w), y+h/3.5, z, 2*z);
////draw body
stroke(0);
fill(249, 137, 244);
ellipse(110+x,y-pigBody, p, p-20);
//draw tail
fill(0);
line(185+x, y-pigTail, x+otherpigTail, y-(2*pigTail));
// Draw payer's head
fill(249, 137, 244);
ellipse(x,y-pigNose,t,t);
// Draw player's eyes
fill(0);
ellipse(x-w/3+1,y-h/2,eyeSize,eyeSize);
ellipse(x+w/3-1,y-h/2,eyeSize,eyeSize);
//Draw nose
stroke(0);
fill(198, 105, 194);
ellipse(x, y, pigNose, pigNose);
//draw ears
stroke(0);
fill(198, 105, 194);
ellipse(x-(w/2),y-h, pigEars, pigEars);
ellipse(x+(w/2),y-h, pigEars, pigEars);
//draw obstacles
fill(value);
ellipse(a, b, s, s);
ellipse(300+a, 200+b, s, s);
ellipse(300-a, 400+b, s, s);
ellipse(300-a, 600+b, s, s);
ellipse(300-a, b, s, s);
ellipse(300+a, 800+b, s, s);
}
I need help turning this code into something similar to this:
/*
This is a very rudimentary virtual pet. It can sit,
lie down, and wag it's tail.
*/
class Pet {
int x, y;
int pose;
int WAG = 1, SLEEP = 2, SIT = 3;
float tailWag, wagSpeed;
Pet(int x, int y) {
this.x = x;
this.y = y;
pose = SIT;
}
// adjust pose and stop tail wagging
void sit() {
pose = SIT;
wagSpeed = 0;
tailWag = 0;
}
// adjust pose and start tail wagging
void wag() {
pose = WAG;
wagSpeed = .1;
}
// adjust pose and stop tail wagging
void sleep() {
pose = SLEEP;
wagSpeed = 0;
tailWag = 0;
}
// draw in selected pose
void draw() {
pushMatrix();
translate(x, y);
if (pose == SIT) {
drawSitting();
}
else if (pose == WAG) {
wagTail();
drawSitting();
}
else {
drawLaying();
}
popMatrix();
}
void drawLaying() {
// needs work :-)
ellipse(0, 0, 150, 60);
}
void wagTail() {
float maxTailWag = .5; // controls how much the tail wags back and forth
tailWag = tailWag + wagSpeed;
// reverse wag direction if the wag limit is reached
if (tailWag > maxTailWag || tailWag < -maxTailWag) {
wagSpeed = -wagSpeed;
}
}
// not pretty but gets the idea across
// origin is the center of the torso
void drawSitting() {
// torso
pushMatrix();
rotate(radians(-30));
ellipse(0, 0, 80, 120);
popMatrix();
ellipse(-20, -70, 60, 60); // head
// nose
pushMatrix();
translate(-55, -55);
rotate(radians(-15));
arc(0, 0, 40, 30, radians(20), radians(310), OPEN);
popMatrix();
// eyes
ellipse(-40, -85, 15, 15); // left eye
ellipse(-25, -80, 15, 15); // right eye
//ear
pushMatrix();
translate(15, -50);
rotate(radians(-20));
ellipse(0, 0, 20, 40);
popMatrix();
//tail
pushMatrix();
translate(40, 30);
rotate(radians(45)+tailWag);
arc(0, -35, 30, 60, radians(-220)-tailWag, radians(80), OPEN);
popMatrix();
// back leg
ellipse(0, 60, 50, 20);
// front leg
pushMatrix();
translate(-50, 30);
rotate(radians(15));
ellipse(0, 0, 30, 60);
popMatrix();
}
}
with classes and whatnot so that I can start working on adding in my own animations for the pet. I'm just not sure where to put everything/how to organize it like that using my drawing.

If I were you, I would start with something simpler. For example, here's a program that uses 4 variables to show a ball bouncing around:
float circleX = 50;
float circleY = 50;
float xSpeed = 1;
float ySpeed = 2;
void draw() {
background(200);
circleX += xSpeed;
if (circleX < 0 || circleX > width) {
xSpeed *= -1;
}
circleY += ySpeed;
if (circleY < 0 || circleY > height) {
ySpeed *= -1;
}
ellipse(circleX, circleY, 20, 20);
}
(source: happycoding.io)
From here, we can encapsulate those 4 variables into a class:
class Circle{
float x;
float y;
float xSpeed;
float ySpeed;
Circle(float x, float y, float xSpeed, float ySpeed){
this.x = x;
this.y = y;
this.xSpeed = xSpeed;
this.ySpeed = ySpeed;
}
}
Now that we have a class, we can use an instance of that class to control our ball.
Circle circle = new Circle(50, 50, 1, 2);
void draw() {
background(200);
circle.x += circle.xSpeed;
if (circle.x < 0 || circle.x > width) {
circle.xSpeed *= -1;
}
circle.y += circle.ySpeed;
if (circle.y < 0 || circle.y > height) {
circle.ySpeed *= -1;
}
ellipse(circle.x, circle.y, 20, 20);
}
class Circle{
float x;
float y;
float xSpeed;
float ySpeed;
Circle(float x, float y, float xSpeed, float ySpeed){
this.x = x;
this.y = y;
this.xSpeed = xSpeed;
this.ySpeed = ySpeed;
}
}
Your code would follow a similar pattern: create a class, encapsulate your data by moving your variables inside the class, and then create an instance of that class and call its methods to draw your figure. Start with something simpler, and just create a class that draws a single circle. Get that working first, and then add variables to that class to draw two circles (a head and a body), and keep working in small steps like that until you're drawing your whole figure.
I really suggest trying something out and posting an MCVE if you get stuck. Good luck.
Shameless self-promotion: I've written a tutorial on creating classes in Processing available here.

How to make sprite bounce of the sides of the screen

I'm using libgdx in java android studio. i have just started. i'm working on android phone. i not using any cameras. all i want is a sprite bounce of all four sides of the screen without tapping. i tried many codes i thought would work but nope. i hope u guys can help me. I'm expecting an answer soon as possible. Thanks
this is what i have:
SpriteBatch batch;
Texture background;
Sprite backgroundsprite;
Sprite ballsprite;
Texture line;
Texture ballimg;
BitmapFont credits;
BitmapFont input;
BitmapFont play;
float dt;
String string = "";
float ballx;
float bally;
float speedx;
float speedy;
Rectangle screenrect;
Rectangle ballrect;
float screenLeft ;
float screenBottom ;
float screenTop ;
float screenRight ;
#Override
public void create() {
batch = new SpriteBatch();
speedx = 5f * dt;
speedy = 5f * dt;
createsprite();
createbackground();
createtext();
ballx = ballsprite.getX();
bally = ballsprite.getY();
}
#Override
public void render() {
Gdx.gl.glClearColor(1, 1, 1, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
dt = Gdx.graphics.getDeltaTime();
ballsprite.setPosition(ballx + speedx,ballsprite.getY());
ballsprite.translateX(speedx);
float left = ballrect.getX();
float bottom = ballrect.getY();
float top = bottom + ballrect.getHeight();
float right = left + ballrect.getWidth();
if(left < screenLeft) {
string = "left";
speedx = 5f*dt;
}
if(right > screenRight)
{
string = "right";
speedx = -5f*dt;
}
if(bottom < screenBottom)
{
string = "bottom";
}
if(top > screenTop)
{
string = "top";
}
batch.begin();
backgroundsprite.draw(batch);
ballsprite.draw(batch);
rendertext();
batch.end();
}
public void createbackground() {
background = new Texture("images/BackgroundGodwin.jpg");
backgroundsprite = new Sprite(background);
backgroundsprite.setSize(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
screenrect = new Rectangle(0,0,Gdx.graphics.getWidth(),Gdx.graphics.getHeight());
screenLeft = screenrect.getX();
screenBottom = screenrect.getY();
screenTop = screenBottom + screenrect.getHeight();
screenRight = screenLeft + screenrect.getWidth();
}
public void createsprite() {
ballimg = new Texture("images/SpriteGodwin.png");
ballsprite = new Sprite(ballimg);
ballsprite.setScale(0.65f);
ballsprite.setPosition(Gdx.graphics.getWidth()/3,Gdx.graphics.getHeight()/2);
ballrect = new Rectangle(ballsprite.getBoundingRectangle());
}
#Override
public void dispose() {
batch.dispose();
ballimg.dispose();
background.dispose();
credits.dispose();
play.dispose();
input.dispose();
line.dispose();
}
public void createtext(){
play = new BitmapFont(Gdx.files.internal("fonts/realfont.fnt"));
play.setColor(com.badlogic.gdx.graphics.Color.GOLD);
credits = new BitmapFont(Gdx.files.internal("fonts/realfont.fnt"));
credits.setColor(com.badlogic.gdx.graphics.Color.GOLD);
input = new BitmapFont(Gdx.files.internal("fonts/realfont.fnt"));
input.setColor(com.badlogic.gdx.graphics.Color.OLIVE);
}
public void rendertext() {
credits.draw(batch, "Maded", Gdx.graphics.getWidth() / 7 - 50, Gdx.graphics.getHeight() / 9);
play.draw(batch, "Touch the Screen to play!!", Gdx.graphics.getWidth() / 2 - 175, Gdx.graphics.getHeight() - 80);
input.draw(batch, string, Gdx.graphics.getWidth() / 2 - 160, Gdx.graphics.getHeight() - 120);
}
}

I made a very simple version of what you want:
public class BouncyGame extends ApplicationAdapter {
SpriteBatch batch;
Texture ball;
float speedX = 3f;
float speedY = 3f;
int x;
int y;
#Override
public void create () {
batch = new SpriteBatch();
ball = new Texture("ball.png");
x = Gdx.graphics.getWidth()/2;
y = Gdx.graphics.getHeight()/2;
}
#Override
public void render () {
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
//When the ball's x position is on either side of the screen.
//The width of the sprite is taken into account.
if (x > Gdx.graphics.getWidth() - ball.getWidth()/2 || x < 0 + ball.getWidth()/2) {
//Here we flip the speed, so it bonces the other way.
speedX = -speedX;
}
//Same as above, but with on the y-axis.
if (y > Gdx.graphics.getHeight() - ball.getHeight()/2 || y < 0 + ball.getHeight()/2) {
speedY = -speedY;
}
//Move the ball according to the speed.
x += speedX;
y += speedY;
batch.begin();
//Draw the ball so the center is at x and y. Normally it would be drawn from the lower left corner.
batch.draw(ball, x - ball.getWidth()/2, y - ball.getHeight()/2);
batch.end();
}
}
It will result in the following:
http://gfycat.com/TatteredCarefreeHapuku
There are numerous ways to improve this code, you could for example use vectors, and I wouldn't recommend using it in your final product, but it might help you figure out how to do something like this for your own project.