Muy buenala pagina de ejemplos.
Adjunto un código de un billar donde se pueden ver los rebotes de las bolas con los lados y otras bolas.
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Font;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.util.Arrays;
import javax.swing.JApplet;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Billard4K extends JPanel implements Runnable, MouseListener, MouseMotionListener {
// GAME STATES
public final int WAITING_TO_START = 0;
public final int WAITING_TO_HIT = 1;
public final int MOVING = 2;
public final int FINISHING = 3;
public int state = 0;
// TABLE
double hR;
double[] tableX;
double[] tableY;
double[] holesX;
double[] holesY;
// BALLS
public int nballs;
public int nBallsOn;
double[] x;
double[] y;
double[] vx;
double[] vy;
double[] nextX;
double[] nextY;
double[] nextVx;
double[] nextVy;
boolean[] borderCollision;
boolean[][] collision;
boolean[] onTable;
double r = 10;
// RENDERING
Image backBuffer;
Image backGround;
// MOUSE
int mX;
int mY;
int mXPost;
int mYPost;
boolean clicked;
// STICK
public final int MAX_STRENGTH = 1000;
int sL = 300;
int actualStep = 0;
public Billard4K() {
super();
this.setBounds(50, 50, 700, 350);
//this.setResizable(false);
//this.setUndecorated(true);
//this.setVisible(true);
JFrame f = new JFrame("Billard4K");
f.add(this);
f.setBounds(0, 0, 700, 380);
f.setResizable(false);
f.setVisible(true);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.requestFocus();
init();
}
public void init() {
initTable();
initBalls();
backBuffer = this.createImage(this.getWidth(), this.getHeight());
//gBackBuffer = backBuffer.getGraphics();
//gBackBuffer.setFont(new Font("Courier", Font.BOLD, 20));
createBackGround();
this.addMouseListener(this);
this.addMouseMotionListener(this);
start();
}
public void initTable() {
hR = 16;
tableX = new double[] {
40,
this.getWidth()-40
};
tableY = new double[] {
tableX[0],
this.getHeight()-tableX[0]
};
holesX = new double[] {
tableX[0] + 20,
this.getWidth()/2,
tableX[1]-20
};
holesY = new double[] {
tableY[0] + 20,
this.tableY[1]-20
};
}
public void initBalls() {
nballs = 16;
x = new double[nballs];
y = new double[nballs];
vx = new double[nballs];
vy = new double[nballs];
nextX = new double[nballs];
nextY = new double[nballs];
nextVx = new double[nballs];
nextVy = new double[nballs];
borderCollision = new boolean[nballs];
collision = new boolean[nballs][nballs];
onTable = new boolean[nballs];
setBalls();
setWhiteBall();
}
public void setWhiteBall() {
x[0] = 1.0 *(holesX[2]-holesX[0]) / 3.0;
y[0] = this.getHeight() / 2;
vx[0] = 0;
vy[0] = 0;
boolean collisions = false;
boolean recolocate = false;
do {
collisions = false;
recolocate = false;
for (int i=1; !collisions && i<nballs; ++i) {
collisions = isBallsCollisionPre(0, i);
}
if (collisions) {
recolocate = true;
y[0] -= r;
if (y[0]<holesY[0]) y[0] = holesY[1]-r;
}
} while (recolocate);
onTable[0] = true;
}
public void setBalls() {
int ball=1;
nBallsOn = nballs - 1;
final double mul = Math.sqrt(3.5);
for (int col=0; col<5; ++col) {
double xN = this.getWidth()*2.0/3.0+col* mul *r;
double yN = this.getHeight()/2-col*r;
for (int row=0; row<=col; ++row) {
x[ball] = xN;
y[ball] = yN;
vx[ball] = 0;
vy[ball] = 0;
onTable[ball] = true;
yN += 2*r;
++ball;
}
}
}
public void createBackGround() {
backGround = this.createImage(this.getWidth(), this.getHeight());
Graphics g = backGround.getGraphics();
g.setColor(Color.GRAY);
g.fillRect(0, 0, this.getWidth(), this.getHeight());
g.setColor(new Color(200, 100, 50).darker());
g.fill3DRect((int)(tableX[0]), (int)(tableY[0]), (int)(tableX[1]-tableX[0]), (int)(tableY[1]-tableY[0]), true);
g.setColor(Color.GREEN);
g.fill3DRect((int)(holesX[0]), (int)(holesY[0]), (int)(holesX[2]-holesX[0]), (int)(holesY[1]-holesY[0]), false);
g.setColor(Color.GREEN.brighter());
g.drawLine((int)(1.0 *(holesX[2]-holesX[0]) / 3.0), (int)holesY[0], (int)(1.0 *(holesX[2]-holesX[0]) / 3.0), (int)holesY[1]);
g.fillOval((int)(1.0 *(holesX[2]-holesX[0]) / 3.0)-2, (int)((holesY[1]+holesY[0])/2)-2, 4, 4);
g.drawArc((int)(1.0 *(holesX[2]-holesX[0]) / 3.0)-20, (int)((holesY[1]+holesY[0])/2)-20, 40, 40, 90, 180);
g.setColor(Color.BLACK);
double radio = hR-2;
for (int iX = 0; iX<3; ++iX) {
for (int iY = 0; iY<2; ++iY) {
g.fillOval((int)(holesX[iX]-radio), (int)(holesY[iY]-radio), (int)(2*radio), (int)(2*radio));
}
}
g.setColor(Color.YELLOW);
g.setFont(new Font("Courier", Font.PLAIN, 11));
g.drawString("http://es.geocities.com/luisja80", this.getWidth()-250, this.getHeight()-10);
}
public void start() {
(new Thread(this)).start();
}
public void run() {
long t1 = System.currentTimeMillis(), t2 = t1;
while (true) {
try {
t2 = System.currentTimeMillis();
switch (state) {
case WAITING_TO_HIT:
calculateNext(t2-t1);
collisions();
update();
break;
case MOVING:
calculateNext(t2-t1);
collisions();
update();
boolean allStopped = true;
for (int i=0; allStopped && i<nballs; ++i) {
allStopped = (vx==0) && (vy==0);
}
if (allStopped) {
state = WAITING_TO_HIT;
if (!onTable[0]) {
setWhiteBall();
}
}
if (nBallsOn==0) {
state = FINISHING;
}
break;
case FINISHING:
setBalls();
setWhiteBall();
state = WAITING_TO_START;
break;
}
render();
repaint();
t1 = t2;
Thread.sleep(10);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
public void collisions() {
borderCollision();
holesCollision();
ballsCollision();
}
public void calculateNext(long millis) {
double segs = millis / 1000.0;
for (int i=0; i<nballs; ++i) if (onTable){
nextX = x + vx * segs;
nextY = y + vy * segs;
vx *= 0.99;
vy *= 0.99;
if (Math.abs(Math.hypot(vx, vy))<2) {
vx = 0;
vy = 0;
}
}
}
public void holesCollision() {
for (int ball = 0; ball < nballs; ++ball) if (onTable[ball]) {
for (int iHX=0; iHX<3; ++iHX) {
for (int iHY=0; iHY<2; ++iHY) {
if (Math.hypot(holesX[iHX]-x[ball], holesY[iHY]-y[ball])<hR) {
onTable[ball] = false;
if (ball!=0)--nBallsOn;
vx[ball] = 0;
vy[ball] = 0;
}
}
}
}
}
public void ballsCollision() {
for (int ball1=0; ball1<nballs; ++ball1) if (onTable[ball1]){
for (int ball2=ball1+1; ball2<nballs; ++ball2) if (onTable[ball2]){
boolean collision;
if(collision = isBallsCollision(ball1,ball2)){
// Adjust position
int cont = 0;
while (cont <10 && collision){
nextX[ball1] = (nextX[ball1] + x[ball1]) / 2;
nextY[ball1] = (nextY[ball1] + y[ball1]) / 2;
nextX[ball2] = (nextX[ball2] + x[ball2]) / 2;
nextY[ball2] = (nextY[ball2] + y[ball2]) / 2;
collision = isBallsCollision(ball1, ball2);
++cont;
}
if (collision) {
nextX[ball1] = x[ball1];
nextY[ball1] = y[ball1];
nextX[ball2] = x[ball2];
nextY[ball2] = y[ball2];
}
// Adjust velocities
double dx = nextX[ball2] - nextX[ball1];
double dy = nextY[ball2] - nextY[ball1];
double dist = Math.hypot(nextX[ball1]-nextX[ball2], nextY[ball1]-nextY[ball2]);
// cos(ang) = dx / dist
// sin(ang) = dy / dist;
// tg(ang) = dy / dx = sin(ang) / cos(ang)
double cos = dx/dist;
double sin = dy/dist;
nextVx[ball2] = vx[ball2] - vx[ball2] * cos * cos;
nextVx[ball2] -= vy[ball2] * cos * sin;
nextVx[ball2] += vx[ball1] * cos * cos;
nextVx[ball2] += vy[ball1] * cos * sin;
nextVy[ball2] = vy[ball2] - vy[ball2] * sin * sin;
nextVy[ball2] -= vx[ball2] * cos * sin;
nextVy[ball2] += vx[ball1] * cos * sin;
nextVy[ball2] += vy[ball1] * sin * sin;
nextVx[ball1] = vx[ball1] - vx[ball1] * cos * cos;
nextVx[ball1] -= vy[ball1] * cos * sin;
nextVx[ball1] += vx[ball2] * cos * cos;
nextVx[ball1] += vy[ball2] * cos * sin;
nextVy[ball1] = vy[ball1] - vy[ball1] * sin * sin;
nextVy[ball1] -= vx[ball1] * cos * sin;
nextVy[ball1] += vx[ball2] * cos * sin;
nextVy[ball1] += vy[ball2] * sin * sin;
vx[ball1] = nextVx[ball1];
vy[ball1] = nextVy[ball1];
vx[ball2] = nextVx[ball2];
vy[ball2] = nextVy[ball2];
}
}
}
}
public boolean isBallsCollisionPre(int ball1, int ball2) {
return Math.hypot(x[ball1]-x[ball2], y[ball1]-y[ball2]) < 2*r;
}
public boolean isBallsCollision(int ball1, int ball2) {
return Math.hypot(nextX[ball1]-nextX[ball2], nextY[ball1]-nextY[ball2]) < 2*r;
}
public void update() {
for (int i=0; i<nballs; ++i) if(onTable){
x = nextX;
y = nextY;
}
}
public void borderCollision() {
for (int i=0; i<nballs; ++i) if (onTable) {
if (nextX-r<holesX[0]) {
nextX = holesX[0] + r;
vx *= -1;
}
else if (nextX+r>holesX[2]){
nextX = holesX[2]-r;
vx *= -1;
}
if (nextY-r<holesY[0]) {
nextY = holesY[0] + r;
vy *= -1;
}
else if (nextY+r>holesY[1]) {
nextY = holesY[1] - r;
vy *= -1;
}
}
}
public void render() {
Graphics gBackBuffer = backBuffer.getGraphics();
gBackBuffer.setFont(new Font("Courier", Font.BOLD, 20));
// TABLE
gBackBuffer.drawImage(backGround, 0, 0, null);
// BALLS
if (onTable[0]) {
gBackBuffer.setColor(Color.WHITE);
gBackBuffer.fillOval((int)(x[0]-r), (int)(y[0]-r), (int)(r*2), (int)(r*2));
}
gBackBuffer.setColor(Color.RED);
for (int i=1; i<nballs; ++i) if (onTable){
gBackBuffer.fillOval((int)(x-r), (int)(y-r), (int)(r*2), (int)(r*2));
}
gBackBuffer.setColor(Color.BLACK);
for (int i=0; i<nballs; ++i) if (onTable) {
gBackBuffer.drawOval((int)(x-r), (int)(y-r), (int)(r*2), (int)(r*2));
}
// STICK
if (state == WAITING_TO_HIT) drawStick(gBackBuffer);
// Initial message
if (state == WAITING_TO_START) {
int mX = this.getWidth()/2-85;
int mY = this.getHeight()/2;
gBackBuffer.setColor(Color.BLACK);
gBackBuffer.drawString("Click to start", mX+2, mY+2);
if (((System.currentTimeMillis()/1000)&1)==0) {
gBackBuffer.setColor(Color.YELLOW);
}
else {
gBackBuffer.setColor(Color.CYAN);
}
gBackBuffer.drawString("Click to start", mX, mY);
}
}
public void drawStick(Graphics gBackBuffer) {
double dist = Math.hypot(x[0]-mX, y[0]-mY);
double dXNormalized = (mX-x[0])/dist;
double dYNormalized = (mY-y[0])/dist;
double strength = (clicked) ? strength()/10 : 1;
double x1 = x[0] + dXNormalized * (r+strength);
double x2 = x[0] + dXNormalized * (r+sL+strength);
double y1 = y[0] + dYNormalized * (r+strength);
double y2 = y[0] + dYNormalized * (r+sL+strength);
// Draw stick
gBackBuffer.setColor(Color.ORANGE);
gBackBuffer.drawLine((int)x1, (int)y1, (int)x2, (int)y2);
// Draw path line
int dot = 0;
int nDots = (clicked)
? (int)(150.0 * (strength / MAX_STRENGTH))
: 15;
double step = 30;
double xStep = step * dXNormalized;
double yStep = step * dYNormalized;
double nextX = x[0] + actualStep * dXNormalized;
double nextY = y[0] + actualStep * dYNormalized;
--actualStep;
actualStep %= step;
gBackBuffer.setColor(Color.WHITE);
for (; dot<nDots; ++dot) {
if (nextX < holesX[0]) {
nextX = holesX[0] - nextX;
nextX = holesX[0] + nextX;
xStep *= -1;
}
else if (nextX > holesX[2]) {
nextX = nextX - holesX[2];
nextX = holesX[2]-nextX;
xStep *= -1;
}
if (nextY < holesY[0]) {
nextY = holesY[0]-nextY;
nextY = holesY[0]+nextY;
yStep *= -1;
}
else if(nextY > holesY[1]) {
nextY = nextY - holesY[1];
nextY = holesY[1] - nextY;
yStep *=-1;
}
gBackBuffer.fillOval((int)nextX-2, (int)nextY-2, 4, 4);
nextX -= xStep;
nextY -= yStep;
}
}
public double strength() {
//return Math.abs(mYPost-mY);
if (clicked) {
return Math.min(MAX_STRENGTH, 10 * Math.hypot(x[0]-mXPost,y[0]-mYPost));
}
else {
return Math.min(MAX_STRENGTH, 10 * Math.hypot(mX-mXPost, mY-mYPost));
}
}
public void paint(Graphics g) {
g.drawImage(backBuffer, 0, 0, null);
}
// MOUSE LISTENER METHODS
public void mousePressed(MouseEvent e) {
clicked = true;
}
public void mouseReleased(MouseEvent e) {
if (state==WAITING_TO_HIT) {
double dStickBall = Math.hypot(x[0]-mX, y[0]-mY);
double dXNormalized = (x[0]-mX)/dStickBall;
double dYNormalized = (y[0]-mY)/dStickBall;
double strength = strength();
if (strength>0) {
state = MOVING;
vx[0] = strength * dXNormalized;
vy[0] = strength * dYNormalized;
}
}
clicked = false;
}
public void mouseClicked(MouseEvent e) {
if (state == WAITING_TO_START) {
state = WAITING_TO_HIT;
}
}
public void mouseEntered(MouseEvent e) {
// EMPTY
}
public void mouseExited(MouseEvent e) {
// EMPTY
}
// MOUSEMOTIONLISTENER METHODS
public void mouseMoved(MouseEvent e) {
mXPost = e.getX();
mYPost = e.getY();
mX = mXPost;
mY = mYPost;
}
public void mouseDragged(MouseEvent e) {
mXPost = e.getX();
mYPost = e.getY();
}
public static void main(String[] args) {
new Billard4K();
}
}
Adjunto un código de un billar donde se pueden ver los rebotes de las bolas con los lados y otras bolas.
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Font;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.util.Arrays;
import javax.swing.JApplet;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Billard4K extends JPanel implements Runnable, MouseListener, MouseMotionListener {
// GAME STATES
public final int WAITING_TO_START = 0;
public final int WAITING_TO_HIT = 1;
public final int MOVING = 2;
public final int FINISHING = 3;
public int state = 0;
// TABLE
double hR;
double[] tableX;
double[] tableY;
double[] holesX;
double[] holesY;
// BALLS
public int nballs;
public int nBallsOn;
double[] x;
double[] y;
double[] vx;
double[] vy;
double[] nextX;
double[] nextY;
double[] nextVx;
double[] nextVy;
boolean[] borderCollision;
boolean[][] collision;
boolean[] onTable;
double r = 10;
// RENDERING
Image backBuffer;
Image backGround;
// MOUSE
int mX;
int mY;
int mXPost;
int mYPost;
boolean clicked;
// STICK
public final int MAX_STRENGTH = 1000;
int sL = 300;
int actualStep = 0;
public Billard4K() {
super();
this.setBounds(50, 50, 700, 350);
//this.setResizable(false);
//this.setUndecorated(true);
//this.setVisible(true);
JFrame f = new JFrame("Billard4K");
f.add(this);
f.setBounds(0, 0, 700, 380);
f.setResizable(false);
f.setVisible(true);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.requestFocus();
init();
}
public void init() {
initTable();
initBalls();
backBuffer = this.createImage(this.getWidth(), this.getHeight());
//gBackBuffer = backBuffer.getGraphics();
//gBackBuffer.setFont(new Font("Courier", Font.BOLD, 20));
createBackGround();
this.addMouseListener(this);
this.addMouseMotionListener(this);
start();
}
public void initTable() {
hR = 16;
tableX = new double[] {
40,
this.getWidth()-40
};
tableY = new double[] {
tableX[0],
this.getHeight()-tableX[0]
};
holesX = new double[] {
tableX[0] + 20,
this.getWidth()/2,
tableX[1]-20
};
holesY = new double[] {
tableY[0] + 20,
this.tableY[1]-20
};
}
public void initBalls() {
nballs = 16;
x = new double[nballs];
y = new double[nballs];
vx = new double[nballs];
vy = new double[nballs];
nextX = new double[nballs];
nextY = new double[nballs];
nextVx = new double[nballs];
nextVy = new double[nballs];
borderCollision = new boolean[nballs];
collision = new boolean[nballs][nballs];
onTable = new boolean[nballs];
setBalls();
setWhiteBall();
}
public void setWhiteBall() {
x[0] = 1.0 *(holesX[2]-holesX[0]) / 3.0;
y[0] = this.getHeight() / 2;
vx[0] = 0;
vy[0] = 0;
boolean collisions = false;
boolean recolocate = false;
do {
collisions = false;
recolocate = false;
for (int i=1; !collisions && i<nballs; ++i) {
collisions = isBallsCollisionPre(0, i);
}
if (collisions) {
recolocate = true;
y[0] -= r;
if (y[0]<holesY[0]) y[0] = holesY[1]-r;
}
} while (recolocate);
onTable[0] = true;
}
public void setBalls() {
int ball=1;
nBallsOn = nballs - 1;
final double mul = Math.sqrt(3.5);
for (int col=0; col<5; ++col) {
double xN = this.getWidth()*2.0/3.0+col* mul *r;
double yN = this.getHeight()/2-col*r;
for (int row=0; row<=col; ++row) {
x[ball] = xN;
y[ball] = yN;
vx[ball] = 0;
vy[ball] = 0;
onTable[ball] = true;
yN += 2*r;
++ball;
}
}
}
public void createBackGround() {
backGround = this.createImage(this.getWidth(), this.getHeight());
Graphics g = backGround.getGraphics();
g.setColor(Color.GRAY);
g.fillRect(0, 0, this.getWidth(), this.getHeight());
g.setColor(new Color(200, 100, 50).darker());
g.fill3DRect((int)(tableX[0]), (int)(tableY[0]), (int)(tableX[1]-tableX[0]), (int)(tableY[1]-tableY[0]), true);
g.setColor(Color.GREEN);
g.fill3DRect((int)(holesX[0]), (int)(holesY[0]), (int)(holesX[2]-holesX[0]), (int)(holesY[1]-holesY[0]), false);
g.setColor(Color.GREEN.brighter());
g.drawLine((int)(1.0 *(holesX[2]-holesX[0]) / 3.0), (int)holesY[0], (int)(1.0 *(holesX[2]-holesX[0]) / 3.0), (int)holesY[1]);
g.fillOval((int)(1.0 *(holesX[2]-holesX[0]) / 3.0)-2, (int)((holesY[1]+holesY[0])/2)-2, 4, 4);
g.drawArc((int)(1.0 *(holesX[2]-holesX[0]) / 3.0)-20, (int)((holesY[1]+holesY[0])/2)-20, 40, 40, 90, 180);
g.setColor(Color.BLACK);
double radio = hR-2;
for (int iX = 0; iX<3; ++iX) {
for (int iY = 0; iY<2; ++iY) {
g.fillOval((int)(holesX[iX]-radio), (int)(holesY[iY]-radio), (int)(2*radio), (int)(2*radio));
}
}
g.setColor(Color.YELLOW);
g.setFont(new Font("Courier", Font.PLAIN, 11));
g.drawString("http://es.geocities.com/luisja80", this.getWidth()-250, this.getHeight()-10);
}
public void start() {
(new Thread(this)).start();
}
public void run() {
long t1 = System.currentTimeMillis(), t2 = t1;
while (true) {
try {
t2 = System.currentTimeMillis();
switch (state) {
case WAITING_TO_HIT:
calculateNext(t2-t1);
collisions();
update();
break;
case MOVING:
calculateNext(t2-t1);
collisions();
update();
boolean allStopped = true;
for (int i=0; allStopped && i<nballs; ++i) {
allStopped = (vx==0) && (vy==0);
}
if (allStopped) {
state = WAITING_TO_HIT;
if (!onTable[0]) {
setWhiteBall();
}
}
if (nBallsOn==0) {
state = FINISHING;
}
break;
case FINISHING:
setBalls();
setWhiteBall();
state = WAITING_TO_START;
break;
}
render();
repaint();
t1 = t2;
Thread.sleep(10);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
public void collisions() {
borderCollision();
holesCollision();
ballsCollision();
}
public void calculateNext(long millis) {
double segs = millis / 1000.0;
for (int i=0; i<nballs; ++i) if (onTable){
nextX = x + vx * segs;
nextY = y + vy * segs;
vx *= 0.99;
vy *= 0.99;
if (Math.abs(Math.hypot(vx, vy))<2) {
vx = 0;
vy = 0;
}
}
}
public void holesCollision() {
for (int ball = 0; ball < nballs; ++ball) if (onTable[ball]) {
for (int iHX=0; iHX<3; ++iHX) {
for (int iHY=0; iHY<2; ++iHY) {
if (Math.hypot(holesX[iHX]-x[ball], holesY[iHY]-y[ball])<hR) {
onTable[ball] = false;
if (ball!=0)--nBallsOn;
vx[ball] = 0;
vy[ball] = 0;
}
}
}
}
}
public void ballsCollision() {
for (int ball1=0; ball1<nballs; ++ball1) if (onTable[ball1]){
for (int ball2=ball1+1; ball2<nballs; ++ball2) if (onTable[ball2]){
boolean collision;
if(collision = isBallsCollision(ball1,ball2)){
// Adjust position
int cont = 0;
while (cont <10 && collision){
nextX[ball1] = (nextX[ball1] + x[ball1]) / 2;
nextY[ball1] = (nextY[ball1] + y[ball1]) / 2;
nextX[ball2] = (nextX[ball2] + x[ball2]) / 2;
nextY[ball2] = (nextY[ball2] + y[ball2]) / 2;
collision = isBallsCollision(ball1, ball2);
++cont;
}
if (collision) {
nextX[ball1] = x[ball1];
nextY[ball1] = y[ball1];
nextX[ball2] = x[ball2];
nextY[ball2] = y[ball2];
}
// Adjust velocities
double dx = nextX[ball2] - nextX[ball1];
double dy = nextY[ball2] - nextY[ball1];
double dist = Math.hypot(nextX[ball1]-nextX[ball2], nextY[ball1]-nextY[ball2]);
// cos(ang) = dx / dist
// sin(ang) = dy / dist;
// tg(ang) = dy / dx = sin(ang) / cos(ang)
double cos = dx/dist;
double sin = dy/dist;
nextVx[ball2] = vx[ball2] - vx[ball2] * cos * cos;
nextVx[ball2] -= vy[ball2] * cos * sin;
nextVx[ball2] += vx[ball1] * cos * cos;
nextVx[ball2] += vy[ball1] * cos * sin;
nextVy[ball2] = vy[ball2] - vy[ball2] * sin * sin;
nextVy[ball2] -= vx[ball2] * cos * sin;
nextVy[ball2] += vx[ball1] * cos * sin;
nextVy[ball2] += vy[ball1] * sin * sin;
nextVx[ball1] = vx[ball1] - vx[ball1] * cos * cos;
nextVx[ball1] -= vy[ball1] * cos * sin;
nextVx[ball1] += vx[ball2] * cos * cos;
nextVx[ball1] += vy[ball2] * cos * sin;
nextVy[ball1] = vy[ball1] - vy[ball1] * sin * sin;
nextVy[ball1] -= vx[ball1] * cos * sin;
nextVy[ball1] += vx[ball2] * cos * sin;
nextVy[ball1] += vy[ball2] * sin * sin;
vx[ball1] = nextVx[ball1];
vy[ball1] = nextVy[ball1];
vx[ball2] = nextVx[ball2];
vy[ball2] = nextVy[ball2];
}
}
}
}
public boolean isBallsCollisionPre(int ball1, int ball2) {
return Math.hypot(x[ball1]-x[ball2], y[ball1]-y[ball2]) < 2*r;
}
public boolean isBallsCollision(int ball1, int ball2) {
return Math.hypot(nextX[ball1]-nextX[ball2], nextY[ball1]-nextY[ball2]) < 2*r;
}
public void update() {
for (int i=0; i<nballs; ++i) if(onTable){
x = nextX;
y = nextY;
}
}
public void borderCollision() {
for (int i=0; i<nballs; ++i) if (onTable) {
if (nextX-r<holesX[0]) {
nextX = holesX[0] + r;
vx *= -1;
}
else if (nextX+r>holesX[2]){
nextX = holesX[2]-r;
vx *= -1;
}
if (nextY-r<holesY[0]) {
nextY = holesY[0] + r;
vy *= -1;
}
else if (nextY+r>holesY[1]) {
nextY = holesY[1] - r;
vy *= -1;
}
}
}
public void render() {
Graphics gBackBuffer = backBuffer.getGraphics();
gBackBuffer.setFont(new Font("Courier", Font.BOLD, 20));
// TABLE
gBackBuffer.drawImage(backGround, 0, 0, null);
// BALLS
if (onTable[0]) {
gBackBuffer.setColor(Color.WHITE);
gBackBuffer.fillOval((int)(x[0]-r), (int)(y[0]-r), (int)(r*2), (int)(r*2));
}
gBackBuffer.setColor(Color.RED);
for (int i=1; i<nballs; ++i) if (onTable){
gBackBuffer.fillOval((int)(x-r), (int)(y-r), (int)(r*2), (int)(r*2));
}
gBackBuffer.setColor(Color.BLACK);
for (int i=0; i<nballs; ++i) if (onTable) {
gBackBuffer.drawOval((int)(x-r), (int)(y-r), (int)(r*2), (int)(r*2));
}
// STICK
if (state == WAITING_TO_HIT) drawStick(gBackBuffer);
// Initial message
if (state == WAITING_TO_START) {
int mX = this.getWidth()/2-85;
int mY = this.getHeight()/2;
gBackBuffer.setColor(Color.BLACK);
gBackBuffer.drawString("Click to start", mX+2, mY+2);
if (((System.currentTimeMillis()/1000)&1)==0) {
gBackBuffer.setColor(Color.YELLOW);
}
else {
gBackBuffer.setColor(Color.CYAN);
}
gBackBuffer.drawString("Click to start", mX, mY);
}
}
public void drawStick(Graphics gBackBuffer) {
double dist = Math.hypot(x[0]-mX, y[0]-mY);
double dXNormalized = (mX-x[0])/dist;
double dYNormalized = (mY-y[0])/dist;
double strength = (clicked) ? strength()/10 : 1;
double x1 = x[0] + dXNormalized * (r+strength);
double x2 = x[0] + dXNormalized * (r+sL+strength);
double y1 = y[0] + dYNormalized * (r+strength);
double y2 = y[0] + dYNormalized * (r+sL+strength);
// Draw stick
gBackBuffer.setColor(Color.ORANGE);
gBackBuffer.drawLine((int)x1, (int)y1, (int)x2, (int)y2);
// Draw path line
int dot = 0;
int nDots = (clicked)
? (int)(150.0 * (strength / MAX_STRENGTH))
: 15;
double step = 30;
double xStep = step * dXNormalized;
double yStep = step * dYNormalized;
double nextX = x[0] + actualStep * dXNormalized;
double nextY = y[0] + actualStep * dYNormalized;
--actualStep;
actualStep %= step;
gBackBuffer.setColor(Color.WHITE);
for (; dot<nDots; ++dot) {
if (nextX < holesX[0]) {
nextX = holesX[0] - nextX;
nextX = holesX[0] + nextX;
xStep *= -1;
}
else if (nextX > holesX[2]) {
nextX = nextX - holesX[2];
nextX = holesX[2]-nextX;
xStep *= -1;
}
if (nextY < holesY[0]) {
nextY = holesY[0]-nextY;
nextY = holesY[0]+nextY;
yStep *= -1;
}
else if(nextY > holesY[1]) {
nextY = nextY - holesY[1];
nextY = holesY[1] - nextY;
yStep *=-1;
}
gBackBuffer.fillOval((int)nextX-2, (int)nextY-2, 4, 4);
nextX -= xStep;
nextY -= yStep;
}
}
public double strength() {
//return Math.abs(mYPost-mY);
if (clicked) {
return Math.min(MAX_STRENGTH, 10 * Math.hypot(x[0]-mXPost,y[0]-mYPost));
}
else {
return Math.min(MAX_STRENGTH, 10 * Math.hypot(mX-mXPost, mY-mYPost));
}
}
public void paint(Graphics g) {
g.drawImage(backBuffer, 0, 0, null);
}
// MOUSE LISTENER METHODS
public void mousePressed(MouseEvent e) {
clicked = true;
}
public void mouseReleased(MouseEvent e) {
if (state==WAITING_TO_HIT) {
double dStickBall = Math.hypot(x[0]-mX, y[0]-mY);
double dXNormalized = (x[0]-mX)/dStickBall;
double dYNormalized = (y[0]-mY)/dStickBall;
double strength = strength();
if (strength>0) {
state = MOVING;
vx[0] = strength * dXNormalized;
vy[0] = strength * dYNormalized;
}
}
clicked = false;
}
public void mouseClicked(MouseEvent e) {
if (state == WAITING_TO_START) {
state = WAITING_TO_HIT;
}
}
public void mouseEntered(MouseEvent e) {
// EMPTY
}
public void mouseExited(MouseEvent e) {
// EMPTY
}
// MOUSEMOTIONLISTENER METHODS
public void mouseMoved(MouseEvent e) {
mXPost = e.getX();
mYPost = e.getY();
mX = mXPost;
mY = mYPost;
}
public void mouseDragged(MouseEvent e) {
mXPost = e.getX();
mYPost = e.getY();
}
public static void main(String[] args) {
new Billard4K();
}
}