Develop Reference

Game of Life in Processing

I want to code my own version of "game of life", in processing 3, but I've come across an error I don't seem to understand. Whenever the code run, the screen keeps going black and white with a few pixels changing but it does not look like game of life.
Any help?
int windowW, windowH, percentAlive, gen;
//windowW is the width of the window, windowH is the height
//percentVlive is the initial percent of alive pixel
//gen is the counter for the generation
color alive, dead;//alive is white and dead is black to represent their respective colors
boolean[][] cells0, cells1;//two arrays for the state of the cells, either alive or dead
boolean zeroOrOne = true;//this is to check which array should be iterated over
void setup() {
size(700, 700);
int width = 700;
int height = 700;
windowW = width;
windowH = height;
percentAlive = 15;
alive = color(255, 255, 255);
dead = color(0, 0, 0);
cells0 = new boolean[width][height];
cells1 = new boolean[width][height];
frameRate(2);
background(alive);
for (int x=0; x<width; x++) {//set the percent of live pixels according to the precentAlive varriable
for (int y=0; y<height; y++) {
int state = (int)random (100);
if (state > percentAlive)
cells0[x][y] = true;
else
cells0[x][y] = false;
}
}
}
void draw() {
gen += 1;//increases the generation every time it draws
drawLoop(zeroOrOne);
WriteGeneration(gen);
if(zeroOrOne){//changes the zeroOrOne value to change the array being iterated over
zeroOrOne = false;
}
else {
zeroOrOne = true;
}
}
void WriteGeneration(int number) {//changes the label on top
fill(0);
rect(0, 0, windowW, 100);
fill(255);
textFont(loadFont("BerlinSansFB-Reg-100.vlw"));
text("Generation " + number, 10, 90);
}
void drawLoop(boolean check) {
loadPixels();
if (check) {//checks which array to iterate thrgough
for (int x = 0; x < windowW; x++) {//iterates through the array
for (int y = 0; y < windowH; y++) {
if (cells0[x][y]) {//checks wether the pixel is alive or dead
pixels[x * 700 + y] = alive;//gets the current pixel
int lives = lives(x, y, check);//checks how many cells are alive around the current cell
if (lives<2) {//these are supposed to put in place the game of life rules
cells1[x][y] = false;
} else if (lives>4) {
cells1[x][y] = false;
} else {
cells1[x][y] = true;
}
} else {
pixels[x * 700 + y] = dead;//gets the current pixel
int lives = lives(x, y, check);//checks how many cells are alive around the current cell
if (lives == 3) {//turns the pixel alive if the condition is met
cells1[x][y] = true;
}
}
}
}
} else {//the same as the top but instead the arrays being updated and read are switched
for (int x = 0; x < windowW; x++) {
for (int y = 0; y < windowH; y++) {
if (cells1[x][y]) {
pixels[x * 700 + y] = alive;
int lives = lives(x, y, check);
if (lives<2) {
cells0[x][y] = false;
} else if (lives>4) {
cells0[x][y] = false;
} else {
cells0[x][y] = true;
}
} else {
pixels[x * 700 + y] = dead;
int lives = lives(x, y, check);
if (lives == 3) {
cells0[x][y] = true;
}
}
}
}
}
updatePixels();
}
int lives(int x, int y, boolean check) {//this just checks how many live pixels are around a given pixel
int lives = 0;
if (x > 1 && y >1 && x < 699 && y < 699) {
if (check) {
if (cells0[x-1][y-1])
lives++;
if (cells0[x][y-1])
lives++;
if (cells0[x+1][y-1])
lives++;
if (cells0[x-1][y])
lives++;
if (cells0[x+1][y])
lives++;
if (cells0[x-1][y+1])
lives++;
if (cells0[x][y+1])
lives++;
if (cells0[x+1][y+1])
lives++;
} else {
if (cells1[x-1][y-1])
lives++;
if (cells1[x][y-1])
lives++;
if (cells1[x+1][y-1])
lives++;
if (cells1[x-1][y])
lives++;
if (cells1[x+1][y])
lives++;
if (cells1[x-1][y+1])
lives++;
if (cells1[x][y+1])
lives++;
if (cells1[x+1][y+1])
lives++;
}
}
return lives;
}

Please post your code as an MCVE. When I try to run your code, I get an error because I don't have the font file your'e trying to load on line 59. That font has nothing to do with your problem, so you should really get rid of it before posting a question.
You've got a lot going on in this code. I understand why you have two arrays, but having them both at the sketch level is only over-complicating your code. You shouldn't need to constantly switch between arrays like that. Instead, I would organize your code like this:
You should only have one array at the sketch level. You can also get rid of the zeroOrOne variable.
Initialize that array however you want.
Create a nextGeneration() that returns a new array based on the current array. This will probably call other functions for counting neighbors and whatnot. But the point is that you can just create a new array every time instead of switching between two global arrays.
This removes all of your duplicated logic.
General notes:
Having 8 if statements to check the neighbors is a bit of overkill. Why not just use a nested for loop?
You should get into the habit of following proper naming conventions. Functions should start with a lower-case letter, and variables should be descriptive- naming something check doesn't really tell the reader anything.
If you still can't get it working, then you're going to have to do some debugging. Add print() statements, or use the Processing editor's debugger to step through the code. Which line behaves differently from what you expect? Then you can post an MCVE of just that line (and whatever hard-coded variables it needs to show the behavior) and we'll go from there. Good luck.

The issues you are having are twofold:
The two cells arrays that you have interfere and make two separate games, when you only want one.
You are updating the cells in your arrays before you get to the end of checking which ones need to be modified.
The way to solve both problems at once is to repurpose the cells1 array. Instead of checking it every other time, make it an array set entirely to false. Then, whenever you want to modify a square in cells0, set that location in cells1 to true, and after you make a marker of each cell you want to change, change them all at once with a separate for loop at the end of the drawLoop() method. This solves both problems in one fell swoop.
Once you have done this, you can remove the check and zeroAndOne variables, as you won't need them anymore. This is what I got for the drawLoop() method after I made the modifications I recommend:
void drawLoop() {
loadPixels();
for (int x = 0; x < windowW; x++) {
for (int y = 0; y < windowH; y++) {
if (cells0[x][y]) {
pixels[x * 700 + y] = alive;
int lives = lives(x, y);
if (lives<2) {
cells1[x][y] = true;
} else if (lives>4) {
cells1[x][y] = true;
}
} else {
pixels[x * 700 + y] = dead;
int lives = lives(x, y);
if (lives == 3) {
cells1[x][y] = true;
}
}
}
}
for (int x = 0; x < windowW; x++) {
for (int y = 0; y < windowH; y++) {
if (cells1[x][y]) {
cells0[x][y] = !cells0[x][y];
cells1[x][y] = false;
}
}
}
updatePixels();
}
I'm sure you can figure out the rest. Good luck!

Method not recognizing the call this in JavaFX application

I'm working on a program that displays circles colliding with the wall and with themselves.
I'm having trouble with the method that will compensate for collisions.
public class bouncyFX extends Application {
public ArrayList<Ball> arr = new ArrayList<Ball>();
public static void main(String[] args) {
launch(args);
}
static Pane pane;
#Override
public void start(final Stage primaryStage) {
pane = new Pane();
final Scene scene = new Scene(pane, 800, 600);
primaryStage.setScene(scene);
primaryStage.show();
pane.setOnMouseClicked(new EventHandler<MouseEvent>() {
public void handle(final MouseEvent event) {
final Ball ball = new Ball(event.getX(), event.getY(), 40, Color.AQUA);
ball.circle.relocate(event.getX(), event.getY());
pane.getChildren().addAll(ball.circle);
arr.add(ball);
final Bounds bounds = pane.getBoundsInLocal();
final Timeline loop = new Timeline(new KeyFrame(Duration.millis(10), new EventHandler<ActionEvent>() {
double deltaX = ball.ballDeltaX;
double deltaY = ball.ballDeltaY;
public void handle(final ActionEvent event) {
ball.circle.setLayoutX(ball.circle.getLayoutX() + deltaX);
ball.circle.setLayoutY(ball.circle.getLayoutY() + deltaY);
final boolean atRightBorder = ball.circle.getLayoutX() >= (bounds.getMaxX()-ball.circle.getRadius());
final boolean atLeftBorder = ball.circle.getLayoutX() <= (bounds.getMinX()+ball.circle.getRadius());
final boolean atBottomBorder = ball.circle.getLayoutY() >= (bounds.getMaxY()-ball.circle.getRadius());
final boolean atTopBorder = ball.circle.getLayoutY() <= (bounds.getMinY()+ball.circle.getRadius());
if(atRightBorder || atLeftBorder)
deltaX *= -1;
if(atBottomBorder || atTopBorder)
deltaY *= -1;
for(int i = 0; i<arr.size(); i++){
for(int j = i+1; j<arr.size()-1; j++){
arr.get(i).collisionMagnitued(arr.get(j));
}
}
}
}));
loop.setCycleCount(Timeline.INDEFINITE);
loop.play();
}
});
}
class Ball{
public Circle circle;
public double ballDeltaX = 3;
public double ballDeltaY = 3;
public void AddBall(Ball b){
arr.add(b);
}
public Ball(double X, double Y, double Rad, Color color) {
circle = new Circle(X, Y, Rad);
circle.setFill(color);
}
private boolean defineCollision(Ball b){
double xd = this.circle.getLayoutX() - b.circle.getLayoutX();
double yd = this.circle.getLayoutY() - b.circle.getLayoutY();
double sumRad = this.circle.getRadius() + b.circle.getRadius();
double squareRad = Math.pow(sumRad, 2);
double distSquare = Math.pow(xd, 2) + Math.pow(yd, 2);
if(distSquare <= squareRad){
return true;
}return false;
}
public void collisionMagnitued(Ball b){
if(this.defineCollision(b)){
double tempDeltaX = ballDeltaX;
double tempDeltaY = ballDeltaY;
if((this.ballDeltaX < 0 && b.ballDeltaX > 0) || (this.ballDeltaX >0 && b.ballDeltaX <0)){
this.ballDeltaX *= -this.ballDeltaX;
b.ballDeltaX *= -b.ballDeltaX;
System.out.println("tredje");
}
if((this.ballDeltaY < 0 && b.ballDeltaY > 0) || (this.ballDeltaY > 0 && b.ballDeltaY < 0)){
this.ballDeltaY *= -this.ballDeltaY;
b.ballDeltaY *= -b.ballDeltaY;
System.out.println("fjärde");
}
else{
System.out.println("Knull");
this.ballDeltaX *= -1;
b.ballDeltaX *= -1;
}
}
}
}
}
The Balls (or circles) are created and are bouncing against the Bounds as expected.
The Collision detection method works as I'm getting print statements inside the last method. However, it seems that there's something wrong with either my ArrayList not being filled with objects or the method trying to compare the parameter Ball and the Ball that calls the method.
Am I way off? Not sure how I'm suppossed to go forth from here.

I see a few issues with your logic:
The first problem is that when the balls "bounce" off the boundaries of the pane, you don't change their ballDeltaX or ballDeltaY values (you just change a local value in the animation loop and use the local value to update the position). So the first time two balls collide, both of their ballDeltaX and ballDeltaY values are equal to +3 (the initial value), which may not represent the actual direction the animation loop is moving them in. In fact, you never actually use any updated values of ballDeltaX or ballDeltaY to compute the new positions; you get the initial values of those variables, copy them into deltaX and deltaY, and then just compute the new positions using deltaX and deltaY. So if you change ballDeltaX and ballDeltaY, the animation loop never sees the change.
The for loops look wrong to me; I don't think they compare the last two elements of the list. (When i = arr.size()-2 in the penultimate iteration of the outer loop, your inner loop is for (int j = arr.size() - 1; j < arr.size() -1; j++) {...} which of course never iterates.) I think you want the bounding conditions to be i < arr.size() - 1 and j < arr.size(), i.e. the other way around.
And then your if/else structure in collisionMagnitued(...) is probably not exactly what you want. I'm not sure what you're trying to implement there, but the else clause only kicks in if the second if is false, and no matter what happens in the first if.
Finally, you are starting a new animation on each mouse click. So, for example, if you have three balls bouncing around, you have three animation loops running, each of which is updating values when the balls collide. You need to start just one loop; it shouldn't do any harm if it refers to an empty list.

Creating graphics objects that never overlap java

I'm making a small balloon game in java and trying to write my code, so that when I create new 'balloon' objects they don't overlap on the screen.
The code I have so far is:
public void newGame(){
UI.clearGraphics();
this.currentScore = 0;
this.totalPopped = 0;
for (int i = 0; i < this.balloons.length-1; i++) {
this.balloons[i] = new Balloon(50 + Math.random()*400, 50 + Math.random()*400);
for (int j = i + 1; j < this.balloons.length; j++) {
if (this.balloons[i] !=null && this.balloons[j] != null && this.balloons[i].isTouching(balloons[j])) {
this.balloons[j] = new Balloon(50 + Math.random()*400, 50+ Math.random()*400);
}
}
this.balloons[i].draw();
}
UI.printMessage("New game: click on a balloon. High score = "+this.highScore);
}
using the draw and isTouching methods:
public void draw(){
UI.setColor(color);
UI.fillOval(centerX-radius, centerY-radius, radius*2, radius*2);
if (!this.popped){
UI.setColor(Color.black);
UI.drawOval(centerX-radius, centerY-radius, radius*2, radius*2);
}
}
/** Returns true if this Balloon is touching the other balloon, and false otherwise
* Returns false if either balloon is popped. */
public boolean isTouching(Balloon other){
if (this.popped || other.popped) return false;
double dx = other.centerX - this.centerX;
double dy = other.centerY - this.centerY;
double dist = other.radius + this.radius;
return (Math.hypot(dx,dy) < dist);
}
how can I write this, so that when the balloons are created, none of them are touching each other?

Right now you have two loops. In the first loop the balloons are created. In the second loop, every balloon is tested against every other loop. Do this test in the first loop: after creating a new balloon, test it against all already existing balloons.

Java moving a image up and down, animated motion

I'm wondering how I can move an image after it has been drawn?
Heres my code for drawing the image:
public int probeX = 500;
public int Minerals = 400;
public int drawProbeA, drawProbe = 0;
public void init() {
// Images Call
probe = getImage(getDocumentBase(), "image/probe.png");
}
public void paint(Graphics g) {
if (drawProbe == 1) {
for (int k = 0; k < drawProbeA; k++) {
g.drawImage(probe, probeX, 474, 50, 50, this);
probeX += 50;
}
probeX = 500;
}
}
public boolean mouseDown(Event e, int x, int y) {
// Clicking on the probe icon
if (x > 1068 && x < 1119 && y > 785 && y < 832 && onNexus == 1
&& Minerals >= 50) {
drawProbeA += 1;
drawProbe = 1;
Minerals -= 50;
}
return true;
}
How can I make it so that after the images are drawn, that hitting an icon will cause the image to be auto moved down the y-axis (like 50 pixels)? Basically, like sliding the image down with an animation? And then stop and then move back up to the orginal spot.
I am using an Applet and would like the animation to loop repeatedly. Thanks.

You need to have a global variable, or another variable somewhere, that indicates that...
The image needs to move
How far in the Y direction it has moved already
Which direction it is going (up or down)
When you have this, you need to add code to your paint() method to draw the image in the correct spot.
You would also need a Timer or Thread that will tell the component to repaint() every few milliseconds, and change your global variables so that it will repaint it lower/higher.
So, as a bit of an example, you might have some global variables like this...
int yPosition = 0;
boolean goingDown = true;
When you need to start your animation, start a Timer that calls the following over and over...
if (goingDown == true){
// if we've gone down 50 pixels, start going up again
if (yPosition <= 0){
goingDown = false;
yPosition++;
}
else {
yPosition--; // move it down 1 pixel
}
}
else {
// if we're going up and we reach 0, go down again
if (yPosition >= 50){
goingDown = true;
yPosition--;
}
else {
yPosition++; // move it up1 pixel
}
}
component.repaint(); // this will call the paint() method
Not your paint method just need to draw your image at the different position. Just change the g.drawImage(probe,probeX,474,50,50,this); like to include the yPosition...
g.drawImage(probe,probeX,474+yPosition,50,50,this);
This should at least point you in the right direction.

Breaking bricks with chain reaction

I am developing a game in java just for fun. It is a ball brick breaking game of some sort.
Here is a level, when the ball hits one of the Orange bricks I would like to create a chain reaction to explode all other bricks that are NOT gray(unbreakable) and are within reach of the brick being exploded.
So it would clear out everything in this level without the gray bricks.
I am thinking I should ask the brick that is being exploded for other bricks to the LEFT, RIGHT, UP, and DOWN of that brick then start the same process with those cells.
//NOTE TO SELF: read up on Enums and List
When a explosive cell is hit with the ball it calls the explodeMyAdjecentCells();
//This is in the Cell class
public void explodeMyAdjecentCells() {
exploded = true;
ballGame.breakCell(x, y, imageURL[thickness - 1][0]);
cellBlocks.explodeCell(getX() - getWidth(),getY());
cellBlocks.explodeCell(getX() + getWidth(),getY());
cellBlocks.explodeCell(getX(),getY() - getHeight());
cellBlocks.explodeCell(getX(),getY() + getHeight());
remove();
ballGame.playSound("src\\ballgame\\Sound\\cellBrakes.wav", 100.0f, 0.0f, false, 0.0d);
}
//This is the CellHandler->(CellBlocks)
public void explodeCell(int _X, int _Y) {
for(int c = 0; c < cells.length; c++){
if(cells[c] != null && !cells[c].hasExploded()) {
if(cells[c].getX() == _X && cells[c].getY() == _Y) {
int type = cells[c].getThickness();
if(type != 7 && type != 6 && type != 2) {
cells[c].explodeMyAdjecentCells();
}
}
}
}
}
It successfully removes my all adjacent cells,
But in the explodeMyAdjecentCells() method, I have this line of code
ballGame.breakCell(x, y, imageURL[thickness - 1][0]);
//
This line tells the ParticleHandler to create 25 small images(particles) of the exploded cell.
Tough all my cells are removed the particleHandler do not create particles for all the removed cells.
The problem was solved youst now, its really stupid.
I had set particleHandler to create max 1500 particles. My god how did i not see that!
private int particleCellsMax = 1500;
private int particleCellsMax = 2500;
thx for all the help people, I will upload the source for creating the particles youst for fun if anyone needs it.
The source code for splitting image into parts was taken from:
Kalani's Tech Blog
//Particle Handler
public void breakCell(int _X, int _Y, String URL) {
File file = new File(URL);
try {
FileInputStream fis = new FileInputStream(file);
BufferedImage image = ImageIO.read(fis);
int rows = 5;
int colums = 5;
int parts = rows * colums;
int partWidth = image.getWidth() / colums;
int partHeight = image.getHeight() / rows;
int count = 0;
BufferedImage imgs[] = new BufferedImage[parts];
for(int x = 0; x < colums; x++) {
for(int y = 0; y < rows; y++) {
imgs[count] = new BufferedImage(partWidth, partHeight, image.getType());
Graphics2D g = imgs[count++].createGraphics();
g.drawImage(image, 0, 0, partWidth, partHeight, partWidth * y, partHeight * x, partWidth * y + partWidth, partHeight * x + partHeight, null);
g.dispose();
}
}
int numParts = imgs.length;
int c = 0;
for(int iy = 0; iy < rows; iy ++) {
for(int ix = 0; ix < colums; ix++) {
if(c < numParts) {
Image imagePart = Toolkit.getDefaultToolkit().createImage(imgs[c].getSource());
createCellPart(_X + ((image.getWidth() / colums) * ix), _Y + ((image.getHeight() / rows) * iy), c, imagePart);
c++;
} else {
break;
}
}
}
} catch(IOException io) {}
}

You could consider looking at this in a more OO way, and using 'tell don't ask'. So you would look at having a Brick class, which would know what its colour was, and its adjacent blocks. Then you would tell the first Block to explode, it would then know that if it was Orange (and maybe consider using Enums for this - not just numbers), then it would tell its adjacent Blocks to 'chain react' (or something like that), these blocks would then decide what to do (either explode in the case of an orange block - and call their adjacent blocks, or not in the case of a grey Block.
I know its quite different from what your doing currently, but will give you a better structured program hopefully.

I would imagine a method that would recursively get all touching cells of a similar color.
Then you can operate on that list (of all touching blocks) pretty easily and break all the ones are haven't been broken.
Also note that your getAdjentCell() method has side effects (it does the breaking) which isn't very intuitive based on the name.
// I agree with Matt that color (or type) should probably be an enum,
// or at least a class. int isn't very descriptive
public enum CellType { GRAY, RED, ORANGE }
public class Cell{
....
public final CellType type;
/**
* Recursively find all adjacent cells that have the same type as this one.
*/
public List<Cell> getTouchingSimilarCells() {
List<Cell> result = new ArrayList<Cell>();
result.add(this);
for (Cell c : getAdjecentCells()) {
if (c != null && c.type == this.type) {
result.addAll(c.getTouchingSimilarCells());
}
}
return result;
}
/**
* Get the 4 adjacent cells (above, below, left and right).<br/>
* NOTE: a cell may be null in the list if it does not exist.
*/
public List<Cell> getAdjecentCells() {
List<Cell> result = new ArrayList<Cell>();
result.add(cellBlock(this.getX() + 1, this.getY()));
result.add(cellBlock(this.getX() - 1, this.getY()));
result.add(cellBlock(this.getX(), this.getY() + 1));
result.add(cellBlock(this.getX(), this.getY() - 1));
return result;
}
}