move a ball one after another - java

I am writing a code of game bean machine(Galton box), its mechanism that one ball fall and move randomly until it get to one of the slots (randomly) and then another ball comes doing the same thing and so on, the problem is that all balls fall at the same time which something I do not want, I want each ball to fall when the current one finishes its travel..can anyone helps me ! Thanks..
here is the code:
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Random;
import java.util.Scanner;
import java.lang.Iterable;
import javax.swing.*;
public class BallPanel extends JPanel {
int x=1, y=1;
Collection <Ball> ball;
public static void main(String [] args){
// create the list
SwingUtilities.invokeLater(new Runnable() {
public void run() {
JFrame frame= new JFrame("Bean game");
frame.add(new BallPanel());
frame.setSize(300,500);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
});
}
public BallPanel() {
JPanel panel = new JPanel();
ball=new ArrayList<>();
for(int i=1;i<=4;i++){
ball.add(new Ball(x,y));
x++;
y++;
}
Timer timer = new Timer(400, new ActionListener()
{
public void actionPerformed(ActionEvent e) {
for (Ball b: ball) {
b.move();repaint();
}
}
});
timer.start();
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
int raduis=10;
int i=0;
int width=(getWidth()/8);
int space=(getWidth()-8*30)/2;
g.setColor(Color.BLACK);
for(i=0;i<=8;i++){
g.drawLine(space+(30*i),getHeight()-5*(raduis) ,space+(30*i) ,getHeight() );
if(i!=0 && i!=8)
g.fillOval(space+(30*i)-5, getHeight()-5*(raduis)-5, 10, 10);
if(i==0){
g.drawLine(space,getHeight()-5*(raduis) , space+((8)*15)-(raduis/2)-15 , getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2);
g.drawLine(space+((8)*15)-(raduis/2)-15 , getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 , space+((8)*15)-(raduis/2)-15 , getHeight()/2-8*8);//vertical line
}
if(i==8){
g.drawLine(space+(30*i), getHeight()-5*(raduis), space+((8)*15)+(raduis/2)+15, getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2);
g.drawLine(space+((8)*15)+(raduis/2)+15 , getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 , space+((8)*15)+(raduis/2)+15 , getHeight()/2-8*8);//vertical line
}
}
int o=1;
for(i=1;i<=8-2;i++){
int k=2;
for(int j=i;j<=8-2;j++){
g.fillOval(space+((i+k)*15)-raduis/2, getHeight()-(5*raduis)-(30*o)-raduis/2, raduis, raduis);
k=k+2;
}o++;
}
for (Ball b : ball) {
b.draw(g);
}
}
public class Ball {
Random rand=new Random();
private int n;
private int raduis = 10;
private int moveRaduis=12;
private int L = 0;
private int R = 0;
private int D = 0;
int x, y;
public Ball(int x, int y){
this.x=x;
this.y=y;
}
public void draw(Graphics g) {
g.setColor(Color.RED);
g.fillOval(getWidth()/2 -raduis/2 + R + L, 0 + D , moveRaduis, moveRaduis);
}
public void move() {
n=1+rand.nextInt(100);
if(n<=51){
D+=15;
if(D<=(getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2))
L=0;
else if(D>getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 && D<getHeight()-5*(raduis))
{
D+=15;
L-=15;
}
else if(D>=getHeight()-5*(raduis))
{
if(D==31*15)D-=15;
D=D;
}
}
else if (n>=51 && n<=100){
D+=15;
if(D<=getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2)
R=0;
else if(D>getHeight()-15-(5*raduis)-(30*(8-2))-raduis/2 && D<getHeight()-5*(raduis))
{
D+=15;
R+=15;
}
else if(D>=getHeight()-5*(raduis)){
if(D==31*15)D-=15;
D=D;
}
}
}
}
}

So, your movement code moves all the balls on each iteration, what you need to do is have an "active" ball, for example...
private Ball activeBall;
Timer timer = new Timer(400, new ActionListener() {
public void actionPerformed(ActionEvent e) {
if (activeBall != null && activeBall.hasCompleted()) {
activeBall = null;
}
if (activeBall == null && ball.size() > 0) {
activeBall = ball.remove(0);
}
if (activeBall != null) {
activeBall.move();
repaint();
}
}
});
You'll need to add in some kind of check to determine the ball has completed it's run though

Related

Eclipse is not running Java method: public void paint (Graphics g)

I'm new to Eclipse, recently swapped from Bluej which ran my codes reliably. In Eclipse, it sometimes runs and sometimes just doesn't run the paint method and I'm not sure why. The same code was running this morning and now it decides to not run and I'm not sure what to do.
Main method:
import java.awt.Container;
import java.awt.Dimension;
import javax.swing.JFrame;
import javax.swing.JPanel;
import Asset.Paddle;
import Asset.Puck;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.event.MouseEvent;
import java.awt.BorderLayout;
public class setup implements KeyListener, MouseListener, MouseMotionListener, Runnable {
int width = 100;
int height = 100;
int scale = 8;
public static setup setup;
JFrame frame;
JPanel main;
Graphic graphic;
Puck puck;
Paddle paddle1,paddle2;
boolean running, up = true, up2 = true;
boolean menu = false, b1, b2, b3;
int winSize;
public setup() {
puck = new Puck((width*scale)/2,(width*scale)/2,20,20);
paddle1 = new Paddle(width*scale/8-20,height*scale/2,20,100);
paddle2 = new Paddle(width*scale/8*7,height*scale/2,20,100);
frame();
}
public void frame() { //Frame setup
frame = new JFrame("Pong");
frame.setSize(width * scale,height * scale);
frame.setLayout(new BorderLayout());
frame.setResizable(false);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container c1 = frame.getContentPane();
Dimension winSize = frame.getSize();
System.out.println(winSize);
graphic = new Graphic(puck,paddle1,paddle2);
graphic.addKeyListener(this);
graphic.addMouseListener(this);
graphic.addMouseMotionListener(this);
main = new JPanel();
main.setLayout(new BorderLayout());
main.setSize(width * scale,height * scale);
main.add(graphic,BorderLayout.CENTER);
start();
c1.add(main);
graphic.requestFocus();
}
public void start() { //running = true
new Thread(this).start();
running = true;
menu = true;
RENDER();
}
public void stop() {
running = false;
}
public void run() { //Game
while(running == true) {
try {
Thread.sleep(10);
} catch (InterruptedException ex) {
ex.printStackTrace();
}
if(puck.getY() < 0 || puck.getY() > height * scale) {
puck.reverseY();
}
paddle1.run();
paddle2.run();
puck.run();
RENDER();
}
}
public void RENDER() {
graphic.UPDATEPADDLE(paddle1,paddle2);
graphic.UPDATEPUCK(puck);
graphic.repaint();
}
public void keyPressed(KeyEvent evt) {
if(evt.getKeyCode() == 81) { // Q
paddle1.setYVel(-2);
up = true;
}
if(evt.getKeyCode() == 65) { // A
paddle1.setYVel(2);
up = false;
}
if(evt.getKeyCode() == 80) { // P
paddle2.setYVel(-2);
up2 = true;
}
if(evt.getKeyCode() == 76) {
paddle2.setYVel(2);
up2 = false;
}
}
public void keyReleased(KeyEvent evt) {
if(evt.getKeyCode() == 81 && up ) { // Q
paddle1.setYVel(0);
}
if(evt.getKeyCode() == 65 && !up) { // A
paddle1.setYVel(0);
}
if(evt.getKeyCode() == 80 && up2) { // P
paddle2.setYVel(0);
}
if(evt.getKeyCode() == 76 && !up2) { // L
paddle2.setYVel(0);
}
}
public void keyTyped(KeyEvent evt) {}
public void mouseClicked(MouseEvent e) {
// if(e.getX() > 375 && e.getX() < 375 + 200 && e.getY() > 400 && e.getY() < 400 + 50) {
// menu = false;
// System.out.println("clicked");
// graphic.UPDATEBUTTON(b1,b2,b3);
// graphic.UPDATEMENU(menu);
// start();
// graphic.repaint();
// }
}
public void mouseEntered(MouseEvent e) {
}
public void mouseExited(MouseEvent e) {
}
public void mousePressed(MouseEvent e) {
}
public void mouseReleased(MouseEvent e) {
}
public static void main(String[] args) {
setup = new setup();
}
public void mouseDragged(MouseEvent e) {
}
public void mouseMoved(MouseEvent e) {
if(e.getX() > 375 && e.getX() < 375 + 200 && e.getY() > 400 && e.getY() < 400 + 50) {
b1 = true;
graphic.UPDATEBUTTON(b1,b2,b3);
graphic.repaint();
}
else {
b1 = false;
graphic.UPDATEBUTTON(b1,b2,b3);
graphic.repaint();
}
}
}
Paddle:
package Asset;
public class Paddle {
double x, y, yVel, h, w;
public Paddle(double xx, double yy, int width, int height) {
x = xx;
y = yy;
h = height;
w = width;
}
public int getX() {
return (int)x;
}
public int getY() {
return (int)y;
}
public int getH() {
return (int)h;
}
public int getW() {
return (int)w;
}
public void setYVel(int yVelocity) {
yVel = yVelocity;
}
public void run() {
y += yVel;
if(y < 0) {
yVel = 0;
y = 0;
}
}
}
Puck:
package Asset;
public class Puck {
double x,y,w,h;
double xVel = 0;
double yVel = 3;
public Puck(double xx, double yy,int width,int height) {
x = xx;
y = yy;
w = width;
h = height;
x++;
}
public void reverseY() {
yVel *= -1;
}
public void reverseX() {
xVel *= -1;
}
public int getX() {
return (int)x;
}
public int getY() {
return (int)y;
}
public int getW() {
return (int)w;
}
public int getH() {
return (int)h;
}
public void run() {
x += xVel;
y += yVel;
}
}
Setup:
import java.awt.*;
import javax.swing.*;
import Asset.Paddle;
import Asset.Puck;
public class Graphic extends JPanel {
private static final long serialVersionUID = 2273791975624707192L;
Puck ppuck;
Paddle ppaddle1,ppaddle2;
boolean mmenu = true;
boolean bb1,bb2,bb3;
public Graphic(Puck puck,Paddle paddle1,Paddle paddle2) {
ppuck = puck;
ppaddle1 = paddle1;
ppaddle2 = paddle2;
}
public void UPDATEMENU(boolean menu) {
mmenu = menu;
}
public void UPDATEPADDLE(Paddle paddle1, Paddle paddle2) {
ppaddle1 = paddle1;
ppaddle2 = paddle2;
}
public void UPDATEPUCK(Puck puck) {
ppuck = puck;
}
public void UPDATEBUTTON(boolean b1,boolean b2, boolean b3) {
bb1 = b1;
bb2 = b2;
bb3 = b3;
}
public void paint (Graphics g) {
super.paint(g);
g.setColor(Color.black);
g.fillRect(0, 0, 1000, 1000);
if (mmenu) { //menu
if(bb1) {
g.setColor(Color.blue);
g.setFont(new Font("TimesRoman", Font.PLAIN, 50));
g.drawString("START", 390, 440);
}
else {
g.setColor(Color.white);
g.setFont(new Font("TimesRoman", Font.PLAIN, 50));
g.drawString("START", 390, 440);
}
}
else {
g.setColor(Color.white);
g.fillOval(ppuck.getX(), ppuck.getY(), ppuck.getW(), ppuck.getH());
g.fillRect(ppaddle1.getX(), ppaddle1.getY(), ppaddle1.getW(), ppaddle1.getH());
g.fillRect(ppaddle2.getX(), ppaddle2.getY(), ppaddle2.getW(), ppaddle2.getH());
}
}
}
So, two "basic" problems...
One, if you modify the UI after the frame is visible, you must call revalidate and repaint too trigger a layout and paint pass. A simpler solution, in your case, would be to call setVisible AFTER you've established the UI
public void frame() { //Frame setup
frame = new JFrame("Pong");
frame.setSize(width * scale, height * scale);
frame.setLayout(new BorderLayout());
frame.setLocationRelativeTo(null);
//frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container c1 = frame.getContentPane();
//...
start();
c1.add(main);
graphic.requestFocus();
frame.setVisible(true);
}
Second...
This one's a little more complicated, but, you start your Thread and then update the state which it relies on to keep running
public void start() { //running = true
new Thread(this).start();
running = true;
menu = true;
RENDER();
}
While very, very unlikely, it's possible that the thread will inspect the state before you change it ... or because of the way the memory model works, won't see the change.
Better to set it before hand...
public void start() { //running = true
running = true;
new Thread(this).start();
menu = true;
RENDER();
}
You should also consider making it volatile
Having said that...
You're going around it all the wrong way.
To start with, don't try and do all the rendering for all the states in the single view, instead, use seperate views to different states (such as the start screen and the game screen).
You could then make use of CardLayout or simply overlay the containers onto of each other when you want to switch between them.
Next, you should avoid using KeyListener, it's troublesome at the best of times. Instead, make us of the key bindings API, then you won't need to post another question about why KeyListener has stopped working.
Next, Swing is single threaded and not thread safe. This means you should not be performing blocking or long running operations within the context of the Event Dispatching Thread or updating the UI or a state the UI depends on from outside of it.
Take a look at Concurrency in Swing for more details.
The simple solution in this case is probably to use a Swing Timer, see How to use Swing Timers for more details.
I would, personally, make the "game" panel responsible for setting up the input and rendering management, but that's me.

Java error for beginner

I just start learning Java. I write a program like this:
Bacteria.class
import java.awt.*;
public class Bacteria extends Creature{
public static final int COLOR_STEP = 256/MAX_AGE;
Bacteria(Board board, int _x, int _y){
super.board = board;
//initialize age, x, y
super.age = 1;
super.x = _x;
super.y = _y;
}
//Draw a circle representing the creature at its position
//This function is done.
public void draw(Graphics g) {
g.setColor(new Color(0, COLOR_STEP * age, 0));
g.fillOval(x * board.CELL_SIZE, y * board.CELL_SIZE, board.CELL_SIZE, board.CELL_SIZE);
}
public void tick() {
//your code
// this is how the creature lives in one tick
// make the creature get older if it is not dead.
// if it's got older than MAX_AGE then it should die
// ...call board.addDead() to register the dead creature
// if it can have baby then try reproduce()
age++;
if (this.canHaveBaby()) {
this.reproduce();
}
//this.reproduce();
if (age > MAX_AGE) {
board.addDead(this);
}
}
}
Creature.class
import java.awt.*;
public class Creature {
public static final int MAX_AGE = 5;
public Board board;
public int age; // age of the creature measures in ticks
public int x; // (x,y) is the position of the creature
public int y;
Creature(Board board, int _x, int _y) {
this.board = board;
//initialize age, x, y
age = 1;
x = _x;
y = _y;
}
public Creature() {
}
//Draw a circle representing the creature at its position
//This function is done.
public void draw(Graphics g){}
public void tick(){}
public void reproduce() {
//your code
// if it can have a baby then produce a baby
// ...in an empty cell next to its cell.
// board.emptyCell() should be used
// ....to check whether a cell in the board is empty
// and call board.addBaby() to place the baby to the board
//int x_current = x, y_current = y;
if(board.emptyCell(x, y+1)){
Creature baby = new Creature(board,x, y+1);
//System.out.println("1");
board.addBaby( baby);
}
else if(board.emptyCell(x+1,y)){
Creature baby = new Creature(board,x+1, y);
board.addBaby(baby);
}
else if(board.emptyCell(x+1,y+1)){
Creature baby = new Creature(board,x+1, y+1);
board.addBaby(baby);
}
else if(board.emptyCell(x-1,y)){
Creature baby = new Creature(board,x-1, y);
board.addBaby(baby);
}
else if(board.emptyCell(x,y-1)){
Creature baby = new Creature(board,x, y-1);
board.addBaby(baby);
}
else if(board.emptyCell(x-1,y-1)){
Creature baby = new Creature(board,x-1, y-1);
board.addBaby(baby);
}
else if(board.emptyCell(x-1,y+1)){
Creature baby = new Creature(board,x-1, y+1);
board.addBaby(baby);
}
else if(board.emptyCell(x+1,y-1)){
Creature baby = new Creature(board,x+1, y-1);
board.addBaby(baby);
}
}
public boolean canHaveBaby() {
//your code
// if the creature is dead or it is too young
// then it cannot have a baby
if(age == 0 || age > MAX_AGE){
return false;
}
return true;
}
public boolean atPosition(int _x, int _y) {
//your code
// return true if the creature is at the position (_x,_y)
// you need this function for board.empty to function correctly
if(_x == x && _y == y){
return true;
}
return false;
}
}
Board.class
import javax.swing.*;
import java.awt.*;
import java.util.ArrayList;
public class Board extends JPanel {
public static final int CELL_SIZE = 10;
private final int rows = 10;
private final int cols = 20;
ArrayList<Creature> creatureList;
ArrayList<Creature> babies, dead;
// ArrayList<Bacteria> bacteriaList;
// ArrayList<Bacteria> babies_bac, dead_bac;
Board() {
super();
setBackground(Color.white);
creatureList = new ArrayList<Creature>();
//creatureList.size();
babies = new ArrayList<Creature>();
dead = new ArrayList<Creature>();
setPreferredSize(new Dimension(cols * CELL_SIZE, rows * CELL_SIZE));
creatureList.add(new Bacteria(this, 1, 1));
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
for (Creature creature: creatureList) {
creature.draw(g);
}
}
public void tick() {
dead = new ArrayList<Creature>();
babies = new ArrayList<Creature>();
for (Creature creature: creatureList) {
creature.tick();
}
creatureList.addAll(babies);
creatureList.removeAll(dead);
}
public void addBaby(Creature baby) {
if (baby != null) babies.add(baby);
}
public void addDead(Creature deadCreature) {
if (deadCreature != null) dead.add(deadCreature);
}
public boolean emptyCell(int x, int y) {
if (x < 0 || y < 0 || x >= cols || y >= rows) return false;
for (Creature creature : creatureList) {
if (creature.atPosition(x, y)) {
return false;
}
}
for (Creature creature : creatureList) {
if (creature.atPosition(x, y)) {
return false;
}
}
return true;
}
public String getPopulation() {
return String.format("%d", creatureList.size());
}
}
and BacteriaSimulator.java
import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class BacteriaSimulator extends JFrame {
private Board board;
private JLabel label;
public BacteriaSimulator() {
initUI();
setTitle("Bacteria Simulator");
setSize(350, 200);
setLocationRelativeTo(null);
setDefaultCloseOperation(EXIT_ON_CLOSE);
}
private void initUI() {
JPanel panel = new JPanel();
board = new Board();
panel.add(board);
label = new JLabel(board.getPopulation());
panel.add(label);
JButton button = new JButton("Tick");
button.addActionListener(new ButtonNextListener());
panel.add(button);
add(panel);
pack();
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
BacteriaSimulator ex = new BacteriaSimulator();
ex.setVisible(true);
}
});
}
private class ButtonNextListener implements ActionListener {
#Override
public void actionPerformed(ActionEvent e) {
board.tick();
label.setText(board.getPopulation());
repaint();
}
}
}
I want Board.class work with creatureList. However, Board is still initialized with a bacteria (creatureList.add(new Bacteria(this, 1, 1));). I got a problem that is Board.class can not run draw() and tick() method which I want. How to draw objects bacteria and make the right method of tick ()? Can you help me! Thank you!
Your draw() and tick() functions are part of Bacteria.java. They cannot be used from Board.java unless you create an instance of Bacteria and then invoke the methods using that.

Is it possible in javax.swing to user two painters in one frame?

I'm recreating the classic snake game. I've already finished coding the snake. What I have to do now is code the walls (that are supposed to be located at the edges of the frame).
As the painter of the snake "repaints" every 30 miliseconds, I thought it would not be really efficient to let this painter draw the walls as well, as the walls stay on the same place during the whole game so it isn't really necessary to redraw the walls every 30 miliseconds.
Thus, I was wondering whether it was possible to have two painters in my game, one that repaints the snake every 30 miliseconds, and one that paints only once (it paints the walls at the beginning of the game)? How should I do that?
These are the most important parts of the code related to the question (full code can be found below this):
//this is in the main class
public Snake(){
painter = new Painter(this);
this.add(painter, BorderLayout.CENTER);
this.setSize(500, 500);
this.setResizable(false);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
this.addKeyListener(this);
this.requestFocusInWindow();
timer = new Timer(30, this);
startGame();
}
public void startGame(){
snakeList = new LinkedList<Point>();
snakeList.addFirst(new Point(10, 10));
snakeSegments(3);
setFood(30, 30);
movementX = 0;
movementY = 0;
timer.start(); //timer triggers gameUpdate();
}
public void gameUpdate(){
snakeMove(movementX, movementY);
snakeInstructor();
snakeEat();
snakeCollision();
painter.repaint();
}
-
// this is in the painter class
#Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.BLACK);
g.fillRect(0, 0, 500, 500);
paintSnake(g);
paintFood(g);
}
This is the full code:
import java.awt.*;
import java.util.*;
import java.awt.event.*;
import javax.swing.JFrame;
import javax.swing.Timer;
public class Snake extends JFrame implements KeyListener, ActionListener{
Painter painter;
LinkedList<Point> snakeList;
Timer timer;
Point foodLocation;
int direction;
int snakeSize;
int movementX, movementY;
public static void main(String[] arg){
new Snake();
}
public Snake(){
painter = new Painter(this);
this.add(painter, BorderLayout.CENTER);
this.setSize(500, 500);
this.setResizable(false);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setVisible(true);
this.addKeyListener(this);
this.requestFocusInWindow();
timer = new Timer(30, this);
startGame();
}
public void startGame(){
snakeList = new LinkedList<Point>();
snakeList.addFirst(new Point(10, 10));
snakeSegments(3);
setFood(30, 30);
movementX = 0;
movementY = 0;
timer.start();
}
public void gameUpdate(){
snakeMove(movementX, movementY);
snakeInstructor();
snakeEat();
snakeCollision();
painter.repaint();
}
public void snakeCollision(){
for(int i = 4; i < getSnakeSize(); i++){
if(getFirst().equals(snakeList.get(i))){
gameOver();
}
}
}
public void gameOver(){
timer.stop();
}
public void snakeEat(){
if(getFirst().equals(getFood())){
newFood();
setSnakeSize();
snakeSegments(4);
}
}
public void snakeSegments(int i){
snakeSize = i;
while(snakeSize > 0){
snakeList.addLast(new Point(getLast()));
snakeSize--;
}
}
public void snakeInstructor(){
int currentDirection = getDirection();
if (currentDirection == 1){
snakeMove(-1, 0);
} else if (currentDirection == 2){
snakeMove(1, 0);
} else if (currentDirection == 3){
snakeMove(0, -1);
} else if (currentDirection == 4){
snakeMove(0, 1);
}
}
public void snakeMove(int directionX, int directionY){
snakeList.getFirst().x = snakeList.getFirst().x + directionX;
snakeList.getFirst().y = snakeList.getFirst().y + directionY;
for(int i = getSnakeSize()-1; i >=1; i--) {
snakeList.get(i).setLocation(snakeList.get(i-1));
}
}
public void newFood(){
Random generator = new Random();
int x = generator.nextInt(49);
int y = generator.nextInt(47);
setFood(x, y);
}
public void setFood(int x, int y){
foodLocation = new Point(x, y);
}
public Point getFood(){
return foodLocation;
}
public void setDirection(int newDirection){
direction = newDirection;
}
public int getDirection (){
return direction;
}
Point getFirst(){
return snakeList.getFirst();
}
Point getLast(){
return snakeList.getLast();
}
Point get(int i){
return snakeList.get(i);
}
public void addFirst(Point p){
snakeList.addFirst(p);
}
public void addLast(Point p){
snakeList.addLast(p);
}
public int getSnakeSize(){
return snakeList.size();
}
public void setSnakeSize(){
snakeSize = getSnakeSize() + 1;
}
#Override
public void actionPerformed(ActionEvent event) {
gameUpdate();
}
#Override public void keyReleased(KeyEvent e){ }
#Override public void keyTyped(KeyEvent e){ }
#Override public void keyPressed(KeyEvent e){
int key = e.getKeyCode();
if((key == KeyEvent.VK_LEFT) && direction != 2){
setDirection(1);
} else if ((key == KeyEvent.VK_RIGHT) && direction != 1){
setDirection(2);
} else if ((key == KeyEvent.VK_UP) && direction != 4){
setDirection(3);
} else if ((key == KeyEvent.VK_DOWN) && direction != 3){
setDirection(4);
} else if (key == KeyEvent.VK_SPACE){
startGame();
}
}
}
-
import java.awt.*;
import java.util.*;
import java.awt.event.*;
import javax.swing.*;
public class Painter extends JPanel{
Snake snake;
public Painter(Snake snake){
this.snake = snake;
}
#Override
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.setColor(Color.BLACK);
g.fillRect(0, 0, 500, 500);
paintSnake(g);
paintFood(g);
}
public void paintSnake(Graphics g){
for(int i = 0; i < snake.getSnakeSize(); i++){
g.setColor(Color.WHITE);
Point p = snake.snakeList.get(i);
g.fillRect(p.x*10, p.y*10, 10, 10);
}
}
public void paintFood(Graphics g){
Point p = snake.getFood();
g.setColor(Color.RED);
g.fillRect(p.x*10, p.y*10, 10, 10);
}
}
Yes and no...
You could make the Painter transparent and overlay the snake on top of the walls, but the call to g.fillRect(0, 0, 500, 500); would make that redundant, as it fills the entire component with the current color...
Seen as the paintComponent method for both painters would be called every time you want to update the UI, it's also kind of pointless.
A better solution would be to render the map to BufferedImage and paint it inside the painter before painting the snake.

Smooth out Java paint animations

I would like to make my app draw moving image a little smoother than how it is currently drawing them. I am not sure what to do to do that.
This is what my main game Thread looks like:
#Override
public void run(){
int delay = 500; //milliseconds
ActionListener taskPerformer = new ActionListener(){
#Override
public void actionPerformed(ActionEvent evt){
Car car = new Car();
int speed = (int)(3 + Math.floor(Math.random() * (6 - 3)));
car.setSpeed(speed);
MainLoop.this.gameObjects.vehicles.add(car.create("/Media/Graphics/blueCar.png", width - 20, 78));
car.driveTo(0, 78);
}
};
new Timer(delay, taskPerformer).start();
try{
while(true){
this.repaint();
for(GameObject go : this.gameObjects.vehicles){
// loops through objects to move them
Vehicle vh = (Vehicle) go;
this.moveVehicle(vh);
if(vh.getX() <= vh.getDestX()){
vh.markForDeletion(true);
}
}
this.gameObjects.destroyVehicles();
Thread.sleep(1);
}
}catch(Exception e){
e.printStackTrace();
}
}
This is a method that calculates the items next x/y position
protected void moveVehicle(Vehicle vh){
int cx = vh.getX();
int dx = vh.getDestX();
int cy = vh.getY();
int dy = vh.getDestY();
// move along x axis
// getMaxSpeed() = Number between 3 and 6
if(cx > dx && vh.movingX() == -1){
vh.setX(cx - vh.getMaxSpeed());
}else if(cx < dx && vh.movingX() == 1){
vh.setX(cx + vh.getMaxSpeed());
}else{
vh.setX(dx);
}
// move along y axis
// getMaxSpeed() = Number between 3 and 6
if(cy > dy && vh.movingY() == -1){
vh.setY(cy - vh.getMaxSpeed());
}else if(cy < dy && vh.movingY() == 1){
vh.setY(cy + vh.getMaxSpeed());
}else{
vh.setY(dy);
}
}
This is my paint method:
#Override
public void paintComponent(Graphics graphics){
super.paintComponent(graphics);
Graphics2D g = (Graphics2D) graphics;
for(GameObject go : gameObjects.vehicles){
g.drawImage(go.getSprite(), go.getX(), go.getY(), this);
}
}
This is possibly more info than needed, but I would like to know, what should I do to make items move from left -> right top -> bottom as smoothly as possible, without much of a performance loss?
Edit: Requested sscce:
package sscce;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.ArrayList;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class Sscce extends JPanel implements Runnable{
ArrayList<Square> squares = new ArrayList<>();
public Sscce(){
JFrame frame = new JFrame();
frame.setSize(500, 500);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.add(this);
Thread t = new Thread(this);
t.start();
}
public static void main(String[] args){
new Sscce();
}
#Override
public void run(){
int delay = 500; //milliseconds
ActionListener taskPerformer = new ActionListener(){
#Override
public void actionPerformed(ActionEvent evt){
Square squ = new Square();
Sscce.this.squares.add(squ);
squ.moveTo(0);
}
};
new Timer(delay, taskPerformer).start();
while(true){
try{
for(Square s : this.squares){
int objX = s.getX();
int desX = s.getDestX();
if(objX <= desX){
System.out.println("removing");
this.squares.remove(s);
}else{
s.setX(s.getX() - 10);
}
}
this.repaint();
Thread.sleep(30);
}catch(Exception e){
}
}
}
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
for(Square s : squares){
g.setColor(Color.blue);
g.fillRect(s.getX(), s.getY(), 50, 50);
}
}
}
class Square{
public int x = 0, y = 0, destX = 0;
public Square(){
this.x = 400;
this.y = 100;
}
public void moveTo(int destX){
this.destX = destX;
}
public int getX(){
return this.x;
}
public int getDestX(){
return this.destX;
}
public void setX(int x){
this.x = x;
}
public int getY(){
return this.y;
}
}
First note, for some reason, I had issues with the JPanel implementing Runnable when running it under MacOS - I have no idea why, but that's why I moved it out.
It is possible for your squares to be update while it is been used to paint which will cause an exception (also, removing elements from a list while you're iterating it isn't a good idea either ;))
Instead, I have two lists. I have a model, which the list can modify and then the paint list which the paint method can use. This allows the thread to modifiy the model, while a paint process is underway.
To prevent any clash, I've added in a lock, which prevents one thread from modifying/accessing the paint list, while another thread has it locked.
Now. Down to the real problem. The main issue you're having isn't the amount of time between the updates, but the distance you are moving. Reduce the distance (to make it slower) and standarise the updates.
Most people won't notice anything much over 25fps, so trying to do much more then that is just wasting CPU cycles and starving the repaint manager, preventing it from actually updating the screen.
It's a balancing act to be sure...
import java.awt.Color;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.locks.ReentrantLock;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
public class TestAnimation11 extends JPanel {
private ArrayList<Square> squares = new ArrayList<>();
private ReentrantLock lock;
public TestAnimation11() {
lock = new ReentrantLock();
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
try {
UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
} catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {
}
JFrame frame = new JFrame();
frame.setSize(500, 500);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
frame.add(TestAnimation11.this);
Thread t = new Thread(new UpdateEngine());
t.start();
}
});
}
public static void main(String[] args) {
new TestAnimation11();
}
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
Square[] paint = null;
lock.lock();
try {
paint = squares.toArray(new Square[squares.size()]);
} finally {
lock.unlock();
}
for (Square s : paint) {
g.setColor(Color.blue);
g.fillRect(s.getX(), s.getY(), 50, 50);
}
}
public class UpdateEngine implements Runnable {
private List<Square> model = new ArrayList<>(squares);
#Override
public void run() {
int ticks = 0;
List<Square> dispose = new ArrayList<>(25);
while (true) {
ticks++;
dispose.clear();
for (Square s : model) {
int objX = s.getX();
int desX = s.getDestX();
if (objX <= desX) {
dispose.add(s);
} else {
s.setX(s.getX() - 2);
}
}
model.removeAll(dispose);
if (ticks == 11) {
Square sqr = new Square();
sqr.moveTo(0);
model.add(sqr);
} else if (ticks >= 25) {
ticks = 0;
}
lock.lock();
try {
squares.clear();
squares.addAll(model);
} finally {
lock.unlock();
}
repaint();
try {
Thread.sleep(40);
} catch (Exception e) {
}
}
}
}
class Square {
public int x = 0, y = 0, destX = 0;
public Square() {
this.x = 400;
this.y = 100;
}
public void moveTo(int destX) {
this.destX = destX;
}
public int getX() {
return this.x;
}
public int getDestX() {
return this.destX;
}
public void setX(int x) {
this.x = x;
}
public int getY() {
return this.y;
}
}
}

Java timer&paintcomponent issues

Hi I am trying to make a red box appear at the bottom of a JPanel .I wish for this box to move to one corner of the screen and stop and then start moving the other way,however i have been unable make the box stop the following is the code i have been working with
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.Timer;
public class JavaApplication13 extends JPanel {
public static void main(String[] args) {
JFrame rough = new JFrame("Panamr");
rough.setVisible(true);
rough.setLocation(1, 1);
rough.setSize(500, 500);
rough.setContentPane(mamals);
}
public static int iomega(int x, int y) {
if (y == 1) {
diget = -5;
time.stop();
}
if (y == 0) {
diget = 5;
}
return diget;
}
static JavaApplication13 mamals = new JavaApplication13();
JavaApplication13() {
setBackground(Color.red);
}
static int oy = 400;
static int ox = 200;
static int diget;
static Timer time = new Timer(100, new ActionListener() {
public int xy = 1;
#Override
public void actionPerformed(ActionEvent e) {
iomega(ox, xy);
if (ox == 500) {
xy = 1;
}
if (ox == 0) {
xy = 0;
}
ox = ox - iomega(ox, oy);
/*if(ox!=500){
ox=ox-diget;
if(ox==0){
diget=-5;}
else {
diget=5;
}
}*/
}
});
boolean test = true;
public void paint(Graphics g) {
super.paint(g);
g.setColor(Color.black);
g.fillRect(ox, oy, 60, 60);
time.start();
repaint();
}
}
your co-ordiantes for the frames/panels size is off, you should calculate this dynamically maybe, or have a final value. Next your xy=0 and xy=1 should be swapped like this:
if (ox == 400) {//this was a larger number then the panel/frame so it went offscreen
xy = 0;//swapped
}
if (ox == 0) {
xy = 1;//swapped
}

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