I am trying to have each brick in my game have a random color, however when I try to do this the whole set of bricks become the same color. How do I make each individual brick a random color? Any help is appreciated.
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Rectangle;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class Game extends JoeApplet implements KeyListener
{
String status;
int ballx = 294; // ball spawn x coordinate
int bally = 640; // ball spawn y coordinate
int batx = 294;
int baty = 654;
int brickx = 32;
int bricky = 50;
double movex = -16; // x speed of ball
double movey = -16; //y speed of ball
int count = 0;
int currentLevel=0;
int score=0; //starts score at 0
int lives=3; //lives start at 3
static boolean right = false;
static boolean left = false;
boolean ballFallDown = false;
boolean bricksOver = false;
Rectangle Ball = new Rectangle(ballx, bally, 14, 14); //creates ball
Rectangle Bat = new Rectangle(batx, baty, 100, 12); //creates bat(paddle)
Rectangle[] Brick = new Rectangle[49]; //creates desired number of bricks
public void paint(Graphics art)
{
switch(currentLevel)
{
case 0:
menuScreen(art);
break;
case 1:
game(art);
break;
}
}
public void menuScreen(Graphics art)
{
setSize(700, 700);
art.setColor(Color.BLACK);
art.fillRect(0, 0, 698, 698);
Color ballcolor=new Color(0,0,66);
art.setColor(ballcolor);
art.fillOval(Ball.x, Ball.y, Ball.width, Ball.height);
Color batcolor=new Color(0,0,66);
art.setColor(batcolor);
art.fill3DRect(Bat.x, Bat.y, Bat.width, Bat.height, true);
art.setColor(Color.green);
art.drawRect(0, 0, 698, 698);
art.setColor(Color.yellow);
Font menu = new Font("Arial", Font.BOLD, 20);
art.setFont(menu);
art.drawString("Brick Breaker", 100,400);
art.drawString("Press P to Play", 100,425);
art.drawString("Press Q to Quit game", 100,450);
for (int i = 0; i < Brick.length; i++)
{
if (Brick[i] != null)
{
Color mycolor=new Color(100,0,0);
art.setColor(mycolor);
art.fill3DRect(Brick[i].x, Brick[i].y, Brick[i].width,
Brick[i].height, true);
}
}
art.setColor(Color.YELLOW);
if (ballFallDown || bricksOver)
{
Font f = new Font("Arial", Font.BOLD, 20);
art.setFont(f);
art.drawString(status, 294, 349);
ballFallDown = false;
bricksOver = false;
}
}
public void game(Graphics art)
{
setSize(700, 700);
art.setColor(Color.BLACK);
art.fillRect(0, 0, 698, 698);
Color ballcolor=new Color(0,0,225);
art.setColor(ballcolor);
art.fillOval(Ball.x, Ball.y, Ball.width, Ball.height);
Color batcolor=new Color(0,0,139);
art.setColor(batcolor);
art.fill3DRect(Bat.x, Bat.y, Bat.width, Bat.height, true);
art.setColor(Color.green);
art.drawRect(0, 0, 698, 698);
for (int i = 0; i < Brick.length; i++)
{
if (Brick[i] != null)
{
Color mycolor=new Color(200,0,0);
art.setColor(mycolor);
art.fill3DRect(Brick[i].x, Brick[i].y, Brick[i].width,
Brick[i].height, true);
}
}
if (ballFallDown || bricksOver)
{
Font f = new Font("Arial", Font.BOLD, 20);
art.setFont(f);
art.drawString(status, 100,425);
ballFallDown = false;
bricksOver = false;
}
for (int i = 0; i < Brick.length; i++)
{
if (Brick[i] != null)
{
if (Brick[i].intersects(Ball))
{
score=score+10;
Brick[i] = null;
movey = -movey;
count++;
}
}
}
if (count == Brick.length)
{
bricksOver = true;
movex=0;
movey=0;
art.setColor(Color.green);
status = "YOU BEAT THE LEVEL!!";
art.drawString("Press E to Exit", 100,450);
art.drawString("Press N for Next Level", 100,475);
repaint();
}
repaint();
Font f = new Font("Arial", Font.BOLD, 20);
art.setFont(f);
art.setColor(Color.white);
art.drawString("Score:"+score, 600, 684);
Ball.x += movex;
Ball.y += movey;
if (left == true)
{
Bat.x -= 18;
right = false;
}
if (right == true)
{
Bat.x += 18;
left = false;
}
if (Bat.x <= 4)
{
Bat.x = 4;
}
else if (Bat.x >= 586)
{
Bat.x = 596;
}
if (Ball.intersects(Bat))
{
movey = -movey-.1;
}
if (Ball.x <= 0 || Ball.x + Ball.height >= 698)
{
movex = -movex;
}
if (Ball.y <= 0)
{
movey = -movey;
}
Font f1 = new Font("Arial", Font.BOLD, 20);
art.setFont(f1);
art.setColor(Color.white);
art.drawString("Lives:"+ lives, 5, 684);
if (Ball.y >= 698 && (bricksOver==false) && lives>0)
{
ballFallDown = true;
art.setColor(Color.red);
status = "";
art.drawString("", 100,450);
lives=lives-1;
ballx = 294;
bally = 640;
Ball = new Rectangle(ballx, bally, 14, 14);
movex = -16;
movey = -16;
repaint();
}
if(lives==0 && Ball.y >= 698)
{
art.setColor(Color.red);
art.drawString("You lost!!", 100,425);
art.drawString("Press E to Exit", 100,450);
}
}
public void init()
{
addKeyListener(this);
for (int i = 0; i < Brick.length; i++) //creates bricks
{
Brick[i] = new Rectangle(brickx, bricky, 40, 20);
if (i == 12) //1st row of bricks
{
brickx = 32;
bricky = 84;
}
if (i == 23) //2nd row of bricks
{
brickx = 82;
bricky = 118;
}
if (i == 32) //3rd row of bricks
{
brickx = 132;
bricky = 152;
}
if (i == 39) //4th row of bricks
{
brickx = 182;
bricky = 186;
}
if (i == 44) //5th row of bricks
{
brickx = 232;
bricky = 220;
}
if (i == 47) //6th row of bricks
{
brickx = 282;
bricky = 254;
}
if (i == 48) //7th row of bricks
{
brickx = 144;
bricky = 132;
}
brickx += 50; //spacing between each brick
}
}
public void restart()
{
ballx = 294;
bally = 640;
batx = 294;
baty = 654;
brickx = 32;
bricky = 50;
Ball = new Rectangle(ballx, bally, 14, 14);
Bat = new Rectangle(batx, baty, 100, 12);
movex = -16;
movey = -16;
ballFallDown = false;
bricksOver = false;
count = 0;
status = null;
for (int i = 0; i < Brick.length; i++) //recreates bricks
{
Brick[i] = new Rectangle(brickx, bricky, 40, 20);
if (i == 12)
{
brickx = 32;
bricky = 84;
}
if (i == 23)
{
brickx = 82;
bricky = 118;
}
if (i == 32)
{
brickx = 132;
bricky = 152;
}
if (i == 39)
{
brickx = 182;
bricky = 186;
}
if (i == 44)
{
brickx = 232;
bricky = 220;
}
if (i == 47)
{
brickx = 282;
bricky = 254;
}
if (i == 48)
{
brickx = 144;
bricky = 132;
}
brickx += 50;
}
repaint();
}
#Override
public void keyPressed(KeyEvent e) //allows each key to do desired action
{
int keyCode = e.getKeyCode();
if (keyCode == KeyEvent.VK_LEFT)
{
left = true;
}
if (keyCode == KeyEvent.VK_RIGHT)
{
right = true;
}
if (keyCode == e.VK_P && currentLevel == 0)
{
currentLevel = 1;
}
else if (keyCode == e.VK_E && currentLevel == 1)
{
currentLevel = 0;
score=0;
lives=3;
restart();
}
else if(keyCode == e.VK_Q)
{
System.exit(0);
}
}
#Override
public void keyReleased(KeyEvent e)
{
int keyCode = e.getKeyCode();
if (keyCode == KeyEvent.VK_LEFT)
{
left = false;
}
if (keyCode == KeyEvent.VK_RIGHT)
{
right = false;
}
}
#Override
public void keyTyped(KeyEvent e)
{
}
public static void main(String[] args)
{
Game prog = new Game();
prog.init();
}
}
I'd throw that code out and start over as you've got both program logic and repaints within your painting methods, neither of which will help you, and your code appears to be one big huge "God" class, all of which will leave you with code that's a horrific nightmare to debug. Recommendations:
Create at least two separate JPanels to display your program with, a GamePanel and a MenuPanel.
Swap these JPanels using a CardLayout.
Do all graphics within a JPanel's paintComponent method and not within a JFrame's or JApplet's paint method.
Don't forget to call the super's painting method, the same method as your override within your override. This is to clean up any dirty pixels.
Separate your program logic from your GUI
This means that you should have a logical non-GUI representation of a single Brick class as well as a collection of these non-GUI bricks.
You can always give your Brick class a Color field, one that the view or gui uses to paint it with.
Create a game-loop, one that you can control, one that doesn't involve calling repaint() within a painting method, since this leads to a completely uncontrollable loop.
Favor use of Key Bindings over KeyListeners.
Try to avoid use of "magic" numbers, such as hard-coding your brick width and spacing in the class itself. Better to use constants as this too makes debugging and enhancing much easier.
For example, some code that's just to demonstrate showing random colors:
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Random;
import javax.swing.*;
public class BrickBreak {
private static void createAndShowGui() {
GamePanel gamePanel = new GamePanel();
JFrame frame = new JFrame("Brick Break");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.getContentPane().add(gamePanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> createAndShowGui());
}
}
// JPanel that draws the game
class GamePanel extends JPanel {
private static final long serialVersionUID = 1L;
private static final Color BACK_GRND = Color.BLACK;
private int prefW;
private int prefH;
private Bricks bricks = new Bricks();
public GamePanel() {
// wide enough to hold the complete top-row of Bricks
// using constants, so GUI automatically resizes if any sizes change
prefW = (Brick.WIDTH + Bricks.X_SPACING) * Bricks.ROW_COUNTS[0] + Bricks.X_SPACING;
prefH = prefW;
setBackground(BACK_GRND);
}
#Override
public Dimension getPreferredSize() {
if (isPreferredSizeSet()) {
return super.getPreferredSize();
}
return new Dimension(prefW, prefH);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
for (Brick brick : bricks) {
brick.draw(g2);
}
}
}
// non-GUI class that represents a logical Brick
class Brick {
public static final int WIDTH = 40;
public static final int HEIGHT = 20;
private int x;
private int y;
private Color color;
private Rectangle boundingRectangle;
public Brick(int x, int y, Color color) {
this.x = x;
this.y = y;
this.color = color;
boundingRectangle = new Rectangle(x, y, WIDTH, HEIGHT);
}
// yeah, I'm mixing some view with model here.
public void draw(Graphics2D g2) {
g2.setColor(color);
g2.fill3DRect(x, y, WIDTH, HEIGHT, true);
}
public int getX() {
return x;
}
public int getY() {
return y;
}
public Color getColor() {
return color;
}
// use this to test for collisions
public boolean contains(Point p) {
return boundingRectangle.contains(p);
}
#Override
public String toString() {
return "Brick [x=" + x + ", y=" + y + ", color=" + color + "]";
}
#Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + x;
result = prime * result + y;
return result;
}
#Override
public boolean equals(Object obj) {
if (this == obj)
return true;
if (obj == null)
return false;
if (getClass() != obj.getClass())
return false;
Brick other = (Brick) obj;
if (x != other.x)
return false;
if (y != other.y)
return false;
return true;
}
}
// logical class that holds all Bricks
// Have class implement Iterable<Brick> so we can easily iterate through its containing
// Brick objects in a for-each loop
class Bricks implements Iterable<Brick> {
public static final int X_SPACING = 10;
public static final int Y_SPACING = X_SPACING;
public static final int[] ROW_COUNTS = {13, 11, 9, 7, 5, 3, 1};
private static final float MIN_SAT = 0.8f;
private List<Brick> brickList;
private Random random = new Random();
public Bricks() {
init(); // safe to call since it's final
}
public final void init() {
// recreate the brickList ArrayList
brickList = new ArrayList<>();
int y = Y_SPACING;
// for each row of bricks
for (int row = 0; row < ROW_COUNTS.length; row++) {
int x = X_SPACING + ((ROW_COUNTS[0] - ROW_COUNTS[row]) / 2) * (X_SPACING + Brick.WIDTH);
// for each column
for (int j = 0; j < ROW_COUNTS[row]; j++) {
// create a random color
float hue = random.nextFloat();
float saturation = MIN_SAT + random.nextFloat() * (1f - MIN_SAT);
float brightness = MIN_SAT + random.nextFloat() * (1f - MIN_SAT);
Color color = Color.getHSBColor(hue, saturation, brightness);
Brick brick = new Brick(x, y, color); // create a new Brick with this Color
brickList.add(brick);
x += X_SPACING + Brick.WIDTH;
}
y += Y_SPACING + Brick.HEIGHT;
}
}
// returns null if no collision
public Brick collision(Point p) {
for (Brick brick : brickList) {
if (brick.contains(p)) {
return brick;
}
}
return null;
}
#Override
public Iterator<Brick> iterator() {
return brickList.iterator();
}
public boolean remove(Brick brick) {
// because Brick implements equals and hashCode, we can do this
return brickList.remove(brick);
}
}
Note that I like using Color's static getHSBColor(float h, float s, float b) method for creating random Colors as this helps me to avoid creating dull Colors, since I can guarantee that the saturation and brightness are above minimum values. All three parameters must be float values between 0f and 1.0f
float hue = random.nextFloat();
float saturation = MIN_SAT + random.nextFloat() * (1f - MIN_SAT);
float brightness = MIN_SAT + random.nextFloat() * (1f - MIN_SAT);
Color color = Color.getHSBColor(hue, saturation, brightness);
Your code has quite a lot of issues, which #HovercaftFullOfEels answer already points out.
As for why your code doesn't work:
for (int i = 0; i < Brick.length; i++)
{
if (Brick[i] != null)
{
Color mycolor=new Color(100,0,0);
art.setColor(mycolor);
art.fill3DRect(Brick[i].x, Brick[i].y, Brick[i].width,
Brick[i].height, true);
}
}
This is the part that renders the bricks. You never create a random-number, but use the same Color for each brick (new Color(100, 0, 0);). Instead introduce a new variable into Brick that specifies the color of each brick and is initialized once with a random color.
The Brick-class would afterwards look like this:
public class Brick{
public int x;
public int y;
...
public Color color;
...
}
The ... are just placeholders for other code that may be content of the class. Regarding public access of Class-variables: Encapsulation is a fundamental concept of OOP and should be used (on encapsulation). E.g. instead of giving direct access to Brick.x consider introducing a method Brick#getX().
Related
I have a problem with a hexagonal grid. I found this code you can see below on Internet, so it's not mine. There are two public classes: hexgame which generates the grid and hexmech which draws and fills every single hexagon. What I'd like to do is basically insert an image into a specific hexagon, but I don't know how to code this and in which part of the classes I should put it. Am I thinking the wrong way?
Thank you very much for your help!
Hexgame
package hex;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class hexgame
{
private hexgame() {
initGame();
createAndShowGUI();
}
final static Color COLOURBACK = Color.WHITE;
final static Color COLOURCELL = Color.WHITE;
final static Color COLOURGRID = Color.BLACK;
final static Color COLOURONE = new Color(255,255,255,200);
final static Color COLOURONETXT = Color.BLUE;
final static Color COLOURTWO = new Color(0,0,0,200);
final static Color COLOURTWOTXT = new Color(255,100,255);
final static Color COLOURSAFE = Color.WHITE;
final static Color COLOURDANGEROUS = Color.LIGHT_GRAY;
final static int EMPTY = 0;
final static int UNKNOWN = -1;
final static int SAFE = 1;
final static int DANGEROUS = 2;
final static int CLICKED = 3;
final static int COLUMN_SIZE = 23;
final static int ROW_SIZE = 14;
final static int HEXSIZE = 45;
final static int BORDERS = 15;
int[][] board = new int[COLUMN_SIZE][ROW_SIZE];
void initGame(){
hexmech.setXYasVertex(false);
hexmech.setHeight(HEXSIZE);
hexmech.setBorders(BORDERS);
for (int i=0;i<COLUMN_SIZE;i++) {
for (int j=0;j<ROW_SIZE;j++) {
board[i][j]=EMPTY;
}
}
board[5][5] = SAFE;
board[5][6] = SAFE;
board[5][7] = SAFE;
board[6][5] = SAFE;
board [6][6] = SAFE;
board[4][4] = UNKNOWN;
}
private void createAndShowGUI()
{
DrawingPanel panel = new DrawingPanel();
JFrame frame = new JFrame("Hex Testing 4");
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
Container content = frame.getContentPane();
content.add(panel);
frame.setSize(825, 630);
frame.setResizable(true);
frame.setLocationRelativeTo( null );
frame.setVisible(true);
}
class DrawingPanel extends JPanel
{
public DrawingPanel()
{
setBackground(COLOURBACK);
MyMouseListener ml = new MyMouseListener();
addMouseListener(ml);
}
public void paintComponent(Graphics g)
{
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g.setFont(new Font("TimesRoman", Font.PLAIN, 15));
super.paintComponent(g2);
for (int i=0;i<COLUMN_SIZE;i++) {
for (int j=0;j<ROW_SIZE;j++) {
if (board[i][j] != UNKNOWN)
hexmech.drawHex(i,j,g2);
}
}
for (int i=0;i<COLUMN_SIZE;i++) {
for (int j=0;j<ROW_SIZE;j++) {
if (board[i][j] != UNKNOWN)
hexmech.fillHex(i,j,board[i][j],g2);
}
}
}
class MyMouseListener extends MouseAdapter {
public void mouseClicked(MouseEvent e) {
int x = e.getX();
int y = e.getY();
Point p = new Point( hexmech.pxtoHex(e.getX(),e.getY()) );
if (p.x < 0 || p.y < 0 || p.x >= COLUMN_SIZE || p.y >= ROW_SIZE) return;
board[p.x][p.y] = CLICKED;
repaint();
}
}
}
}
Hexmech
package hex;
import java.awt.*;
import javax.swing.*;
public class hexmech
{
#define HEXEAST 0
#define HEXSOUTHEAST 1
#define HEXSOUTHWEST 2
#define HEXWEST 3
#define HEXNORTHWEST 4
#define HEXNORTHEAST 5
public final static boolean orFLAT= true;
public final static boolean orPOINT= false;
public static boolean ORIENT= orFLAT;
public static boolean XYVertex=true;
private static int BORDERS=50
private static int s=0; // length of one side
private static int t=0; // short side of 30o triangle outside of each hex
private static int r=0; // radius of inscribed circle (centre to middle of each side). r= h/2
private static int h=0; // height. Distance between centres of two adjacent hexes. Distance between two opposite sides in a hex.
public static void setXYasVertex(boolean b) {
XYVertex=b;
}
public static void setBorders(int b){
BORDERS=b;
}
public static void setSide(int side) {
s=side;
t = (int) (s / 2); //t = s sin(30) = (int) CalculateH(s);
r = (int) (s * 0.8660254037844);
h=2*r;
}
public static void setHeight(int height) {
h = height;
r = h/2; // r = radius of inscribed circle
s = (int) (h / 1.73205); // s = (h/2)/cos(30)= (h/2) / (sqrt(3)/2) = h / sqrt(3)
t = (int) (r / 1.73205); // t = (h/2) tan30 = (h/2) 1/sqrt(3) = h / (2 sqrt(3)) = r / sqrt(3)
}
public static Polygon hex (int x0, int y0) {
int y = y0 + BORDERS;
int x = x0 + BORDERS;
if (s == 0 || h == 0) {
System.out.println("ERROR: size of hex has not been set");
return new Polygon();
}
int[] cx,cy;
if (XYVertex)
cx = new int[] {x,x+s,x+s+t,x+s,x,x-t}; //this is for the top left vertex being at x,y. Which means that some of the hex is cutoff.
else
cx = new int[] {x+t,x+s+t,x+s+t+t,x+s+t,x+t,x}; //this is for the whole hexagon to be below and to the right of this point
cy = new int[] {y,y,y+r,y+r+r,y+r+r,y+r};
return new Polygon(cx,cy,6);
}
public static void drawHex(int i, int j, Graphics2D g2) {
int x = i * (s+t);
int y = j * h + (i%2) * h/2;
Polygon poly = hex(x,y);
g2.setColor(hexgame.COLOURCELL);
//g2.fillPolygon(hexmech.hex(x,y));
g2.fillPolygon(poly);
g2.setColor(hexgame.COLOURGRID);
g2.drawString(String.format("%c;%d", 'A'+i, j+1), x+20, y+40);
g2.drawPolygon(poly);
}
public static void fillHex(int i, int j, int n, Graphics2D g2) {
char c='o';
int x = i * (s+t);
int y = j * h + (i%2) * h/2;
/*if (n < 0) {
g2.setColor(hexgame.COLOURONE);
g2.fillPolygon(hex(x,y));
g2.setColor(hexgame.COLOURONETXT);
c = (char)(-n);
g2.drawString(""+c, x+r+BORDERS, y+r+BORDERS+4); //FIXME: handle XYVertex
//g2.drawString(x+","+y, x+r+BORDERS, y+r+BORDERS+4);
}
if (n > 0) {
g2.setColor(hexgame.COLOURTWO);
g2.fillPolygon(hex(x,y));
g2.setColor(hexgame.COLOURTWOTXT);
c = (char)n;
if (n==3) {
g2.setColor(hexgame.COLOURTWO);
g2.fillPolygon(hex(x,y));
g2.setColor(hexgame.COLOURTWOTXT);
}
}
public static Point pxtoHex(int mx, int my) {
Point p = new Point(-1,-1);
//correction for BORDERS and XYVertex
mx -= BORDERS;
my -= BORDERS;
if (XYVertex) mx += t;
int x = (int) (mx / (s+t));
int y = (int) ((my - (x%2)*r)/h);
int dx = mx - x*(s+t);
int dy = my - y*h;
if (my - (x%2)*r < 0) return p; // prevent clicking in the open halfhexes at the top of the screen
//System.out.println("dx=" + dx + " dy=" + dy + " > " + dx*r/t + " <");
//even columns
if (x%2==0) {
if (dy > r) { //bottom half of hexes
if (dx * r /t < dy - r) {
x--;
}
}
if (dy < r) { //top half of hexes
if ((t - dx)*r/t > dy ) {
x--;
y--;
}
}
} else { // odd columns
if (dy > h) { //bottom half of hexes
if (dx * r/t < dy - h) {
x--;
y++;
}
}
if (dy < h) { //top half of hexes
//System.out.println("" + (t- dx)*r/t + " " + (dy - r));
if ((t - dx)*r/t > dy - r) {
x--;
}
}
}
p.x=x;
p.y=y;
return p;
}
In your implementation of paintComponent(), invoke setClip() with a suitable Shape, such as Polygon. You can size and translate the Polygon to match the destination hexagon using the createTransformedShape() method of AffineTransform. Use the coordinates of the polygon's boundary as the basis for the coordinates used in your call to drawImage(). A related example using Ellipse2D is shown here.
I am using drawString() to write text on the string, but nothing shows up. I set the color to white and set the coordinates to (100,100). Is there anything else that I am doing wrong?
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.JPanel;
public class Screen extends JPanel implements Runnable {
private static final long serialVersionUID = 1L;
public static final int WIDTH = 800, HEIGHT = 800;
private Thread thread;
private boolean running = false;
private BodyPart b;
private ArrayList<BodyPart> snake;
private Apple apple;
private ArrayList<Apple> apples;
private Random r;
private int xCoor = 20, yCoor = 20;
private int size = 10;
private int score = 0;
private boolean right = true, left = false, up = false, down = false;
private int ticks = 0;
private Key key;
public Screen() {
setFocusable(true);
key = new Key();
addKeyListener(key);
setPreferredSize(new Dimension(WIDTH, HEIGHT));
r = new Random();
snake = new ArrayList<BodyPart>();
apples = new ArrayList<Apple>();
start();
}
public void reset() {
snake.clear();
apples.clear();
xCoor = 20;
yCoor = 20;
size = 10;
score = 0;
running = true;
}
public void tick() {
if(snake.size() == 0) {
b = new BodyPart(xCoor, yCoor, 20);
snake.add(b);
}
if(apples.size() == 0) {
int xCoor = r.nextInt(40);
int yCoor = r.nextInt(40);
apple = new Apple(xCoor, yCoor, 20);
apples.add(apple);
}
for(int i = 0; i < apples.size(); i++) {
if(xCoor == apples.get(i).getxCoor() && yCoor == apples.get(i).getyCoor()) {
size++;
apples.remove(i);
score += 10;
i--;
}
}
for(int i = 0; i < snake.size(); i++) {
if(xCoor == snake.get(i).getxCoor() && yCoor == snake.get(i).getyCoor()) {
if(i != snake.size() - 1) {
reset();
}
}
}
if(xCoor < 0) xCoor = 40;
if(xCoor > 40) xCoor = 0;
if(yCoor < 0) yCoor = 40;
if(yCoor > 40) yCoor = 0;
ticks++;
if(ticks > 250000) {
if(right) xCoor++;
if(left) xCoor--;
if(up) yCoor--;
if(down) yCoor++;
ticks = 185000;
b = new BodyPart(xCoor, yCoor, 20);
snake.add(b);
if(snake.size() > size) {
snake.remove(0);
}
}
}
public void paint(Graphics g) {
g.clearRect(0, 0, WIDTH, HEIGHT);
g.drawString("Score: " + score, 100, 100);
g.setColor(Color.WHITE);
g.setColor(new Color(20, 50, 0));
g.fillRect(0, 0, WIDTH, HEIGHT);
g.setColor(Color.BLACK);
for(int i = 0; i < WIDTH / 20; i++) {
g.drawLine(i * 20, 0, i * 20, HEIGHT);
}
for(int i = 0; i < HEIGHT / 20; i++) {
g.drawLine(0, i * 20, WIDTH, i * 20);
}
for(int i = 0; i < snake.size(); i++) {
snake.get(i).draw(g);
}
for(int i = 0; i < apples.size(); i++) {
apples.get(i).draw(g);
}
}
public void start() {
running = true;
thread = new Thread(this, "Game Loop");
thread.start();
}
public void stop() {
running = false;
try {
thread.join();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void run() {
while(running) {
tick();
repaint();
}
}
private class Key implements KeyListener {
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
if(key == KeyEvent.VK_RIGHT && !left) {
up = false;
down = false;
right = true;
}
if(key == KeyEvent.VK_LEFT && !right) {
up = false;
down = false;
left = true;
}
if(key == KeyEvent.VK_UP && !down) {
left = false;
right = false;
up = true;
}
if(key == KeyEvent.VK_DOWN && !up) {
left = false;
right = false;
down = true;
}
}
}
The order in which you do things is very important, remember, painting in Swing is like painting on paper, if you paint the text first, then paint over it, it will no longer be visible...
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.setColor(new Color(20, 50, 0));
g.fillRect(0, 0, WIDTH, HEIGHT);
g.setColor(Color.BLACK);
for (int i = 0; i < WIDTH / 20; i++) {
g.drawLine(i * 20, 0, i * 20, HEIGHT);
}
for (int i = 0; i < HEIGHT / 20; i++) {
g.drawLine(0, i * 20, WIDTH, i * 20);
}
for (int i = 0; i < snake.size(); i++) {
snake.get(i).draw(g);
}
for (int i = 0; i < apples.size(); i++) {
apples.get(i).draw(g);
}
g.setColor(Color.WHITE);
g.drawString("Score: " + score, 100, 100);
}
Don't override paint, override paintComponent, you've circumvented the painting process, meaning you could end up with all sorts of nasty glitches
Call super.paintComponent
Take a look at Painting in AWT and Swing and Performing Custom Painting for more details about how painting is done.
Swing is also not thread safe and you need to be careful any time you are changing anything that the paint process uses to update the UI, as painting may occur at any time and for any reason.
Consider using a Swing Timer instead of Thread. The timer executes it's tick events within the context of the Event Dispatching Thread, making it safer to update the UI from within. See Creating a GUI With JFC/Swing
You have a few things in the wrong order. When painting, you need to paint in the correct order, otherwise you will paint over the top of other objects.
So, in your code, the first 5 lines of the paint() method should look like this... (note the same code, but a different order)
g.clearRect(0, 0, WIDTH, HEIGHT);
g.setColor(new Color(20, 50, 0));
g.fillRect(0, 0, WIDTH, HEIGHT);
g.setColor(Color.WHITE);
g.drawString("Score: " + score, 100, 100);
You need to paint the background color first. Then you can paint the String on top of it.
I'm trying to write my first game in Java. I followed some tutorials and learned how to load and update a background using a Canvas and how to load and move a player sprite. I did these two separately and they worked fine, but when I put the two together and try to move the player, the game slows down to the point that it is unplayable. This only happens when I hold down an arrow key to move the player; the game actually runs "smoothly" if I rapidly tap the arrow key. After quite a bit of testing, I'm convinced that the problem occurs when the background is redrawn each frame. Any other improvements would also be appreciated.
Code (All of it):
Game.Java:
package Game;
import Level.Level;
import Player.Player;
import Sprites.SpriteSheetLoader;
import java.awt.Canvas;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;
import java.awt.image.DataBufferInt;
import javax.swing.JFrame;
public class Game extends Canvas implements Runnable {
// Set dimensions of the game.
public static final int HEIGHT = 320;
public static final int WIDTH = 480;
public static final int SCALE = 2;
public static Dimension GAME_DIM = new Dimension(WIDTH * SCALE, HEIGHT * SCALE);
private BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_ARGB);
private int[] pixels = ((DataBufferInt) image.getRaster().getDataBuffer()).getData();
public SpriteSheetLoader loader;
public Screen screen;
public Level level;
public InputHandler input = new InputHandler(this);
public Player player = new Player();
private boolean running = false;
private boolean moving = true;
private int FPS = 60;
private long targetTime = 1000 / FPS;
// Set character's starting position at the center. I have no idea why I had to add the "- 50" to each value.
public int x = GAME_DIM.width / 2 - 50;
public int y = GAME_DIM.height / 2 - 50;
public int xScroll = 0;
public int yScroll = 0;
public int col = 0;
public int row = 0;
public int ticks = 0;
public int frame = 0;
public static void main(String[] args) {
Game game = new Game();
game.setPreferredSize(new Dimension(GAME_DIM));
game.setMaximumSize(new Dimension(GAME_DIM));
game.setMinimumSize(new Dimension(GAME_DIM));
JFrame frame = new JFrame("Valkyrie Game");
frame.add(game);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setResizable(true);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
game.start();
}
public void start() {
running = true;
new Thread(this).start();
}
public Game() {
}
public void init() {
loader = new SpriteSheetLoader();
screen = new Screen(WIDTH, HEIGHT);
level = new Level(16, 16);
}
public void run() {
init();
long start, elapsed, wait;
while (running) {
start = System.nanoTime();
render();
tick();
elapsed = System.nanoTime() - start;
//System.out.println("Elapsed: " + elapsed);
wait = targetTime - elapsed / 1000000;
if(wait < 0) {
wait = 5;
}
try {
Thread.sleep(wait);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
public void stop() {
running = false;
}
public void tick() {
// Movement
if (input.right) {
xScroll++;
player.setAnimation(player.walkRight);
//x++;
row = 2;
ticks++;
if(ticks < 10) {
frame = 1;
} else if(ticks == 10) {
frame = 2;
} else if(ticks == 20) {
frame = 3;
} else if(ticks == 30) {
frame = 2;
} else if(ticks == 40) {
frame = 1;
} else if(ticks == 50) {
ticks = 0;
frame = 0;
}
moving = true;
} else if (input.left) {
xScroll--;
player.setAnimation(player.walkLeft);
//x--;
row = 1;
ticks++;
if(ticks < 10) {
frame = 1;
} else if(ticks == 10) {
frame = 2;
} else if(ticks == 20) {
frame = 3;
} else if(ticks == 30) {
frame = 2;
} else if(ticks == 40) {
frame = 1;
} else if(ticks == 50) {
ticks = 0;
frame = 0;
}
moving = true;
} else if (input.up) {
yScroll--;
player.setAnimation(player.walkUp);
//y--;
row = 3;
ticks++;
if(ticks < 10) {
frame = 1;
} else if(ticks == 10) {
frame = 2;
} else if(ticks == 20) {
frame = 3;
} else if(ticks == 30) {
frame = 2;
} else if(ticks == 40) {
frame = 1;
} else if(ticks == 50) {
ticks = 0;
frame = 0;
}
moving = true;
} else if (input.down) {
yScroll++;
player.setAnimation(player.walkDown);
//y++;
row = 0;
ticks++;
if(ticks < 10) {
frame = 1;
} else if(ticks == 10) {
frame = 2;
} else if(ticks == 20) {
frame = 3;
} else if(ticks == 30) {
frame = 2;
} else if(ticks == 40) {
frame = 1;
} else if(ticks == 50) {
ticks = 0;
frame = 0;
}
moving = true;
}
if (!input.down && !input.left && !input.right && !input.up) {
player.setAnimation(player.stand);
frame = 0;
ticks = 1;
moving = false;
}
//System.out.println("Tick: " + ticks);
}
public void render() {
BufferStrategy bs = getBufferStrategy();
if (bs == null) {
createBufferStrategy(3);
requestFocus();
return;
}
do {
Graphics g = bs.getDrawGraphics();
try {
for (int i = 0; i < ticks; i++) {
g.drawImage(image, 0, 0, getWidth(), getHeight(), null);
g.drawImage(player.Player(frame, row), x, y, null);
level.renderBackground(xScroll, yScroll, screen);
for (int y = 0; y < this.screen.h; y++) {
for (int x = 0; x < screen.w; x++) {
pixels[x + (y * WIDTH)] = screen.pixels[x + (y * screen.w)];
}
}
}
} finally {
g.dispose();
}
bs.show();
this.update(bs.getDrawGraphics());
} while (bs.contentsLost());
// Graphics g = bs.getDrawGraphics();
//
// g.dispose();
// bs.show();
}
}
InputHandler.Java:
package Game;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class InputHandler implements KeyListener {
public boolean up = false;
public boolean down = false;
public boolean left = false;
public boolean right = false;
public InputHandler(Game game) {
game.addKeyListener(this);
}
public void toggle(KeyEvent ke, boolean pressed) {
int keyCode = ke.getKeyCode();
if(keyCode == KeyEvent.VK_UP) up = pressed;
if(keyCode == KeyEvent.VK_DOWN) down = pressed;
if(keyCode == KeyEvent.VK_LEFT) left = pressed;
if(keyCode == KeyEvent.VK_RIGHT) right = pressed;
}
public void keyTyped(KeyEvent e) {
}
public void keyPressed(KeyEvent e) {
toggle(e, true);
}
public void keyReleased(KeyEvent e) {
toggle(e, false);
}
}
Screen.Java:
package Game;
import Sprites.Sprite;
public class Screen {
public int w, h;
int xOffset = 0;
int yOffset = 0;
public int[] pixels;
public Screen(int w, int h) {
this.w = w; // 480
this.h = h; // 320
pixels = new int[w * h]; // 153600
}
public void renderSprite(int xPos, int yPos, Sprite sprite) {
int height = sprite.h;
int width = sprite.w;
xPos -= xOffset;
yPos -= yOffset;
for(int y = 0; y < height; y++) {
if(yPos + y < 0 || yPos + y >= h) continue;
for(int x = 0; x < width; x++) {
if(xPos + x < 0 || xPos + x >= w) continue;
int col = sprite.pixels[x + (y * height)];
if(col != -65281 && col < 0) pixels[(x + xPos) + (y + yPos) *w]= col;
}
}
}
public void setOffs(int xOffs, int yOffs) {
xOffset = xOffs;
yOffset = yOffs;
}
}
Level.Java:
package Level;
import Game.Screen;
import Sprites.Sprite;
import Sprites.Sprites;
import Tiles.Tile;
public class Level {
int w, h;
public int[] tiles;
public Level(int w, int h) {
this.w = w;
this.h = h;
tiles = new int[w * h];
loadMap(0, 0, 0, 0);
}
public void renderBackground(int xScroll, int yScroll, Screen screen) {
int xo = xScroll >> 4;
int yo = yScroll >> 4;
int w = (screen.w + 15) >> 4;
int h = (screen.h + 15) >> 4;
screen.setOffs(xScroll, yScroll);
for(int y = yo; y <= h + yo; y++) {
for(int x = xo; x <= w + xo; x++) {
getTile(x, y).render(x, y, screen);
}
}
screen.setOffs(0, 0);
}
public Tile getTile(int x, int y) {
if(x < 0 || y < 0 || x >= w || y >= h) return Tile.rockTile;
return Tile.tiles[tiles[x + y * w]];
}
public void loadMap(int x0, int y0, int x1, int y1) {
Sprite sprite = Sprites.level[x0][y0];
for(int y = 0; y < sprite.h; y++) {
for(int x = 0; x < sprite.w; x++) {
if(sprite.pixels[x + y * sprite.h] == -9276814) {
tiles[x + x1 + (y + y1) * h] = Tile.rockTile.id;
} else {
tiles[x + x1 + (y + y1) * h] = Tile.grassTile.id;
}
}
}
}
}
Player.Java:
package Player;
import Animation.Animation;
import Sprites.Sprite;
import java.awt.image.BufferedImage;
public class Player {
// Images for each animation
private BufferedImage[] walkingLeft = {Sprite.getSprite(0, 1), Sprite.getSprite(1, 1), Sprite.getSprite(2, 1)}; // Gets the upper left images of my sprite sheet
private BufferedImage[] walkingRight = {Sprite.getSprite(0, 2), Sprite.getSprite(1, 2), Sprite.getSprite(2, 2)};
private BufferedImage[] walkingUp = {Sprite.getSprite(0, 3), Sprite.getSprite(1, 3), Sprite.getSprite(2, 3)};
private BufferedImage[] walkingDown = {Sprite.getSprite(0, 0), Sprite.getSprite(1, 0), Sprite.getSprite(2, 0)};
private BufferedImage[] standing = {Sprite.getSprite(1, 0)};
// These are animation states.
public Animation walkLeft = new Animation(walkingLeft, 10);
public Animation walkRight = new Animation(walkingRight, 10);
public Animation walkUp = new Animation(walkingUp, 10);
public Animation walkDown = new Animation(walkingDown, 10);
public Animation stand = new Animation(standing, 10);
// This is the actual animation
public Animation animation = stand;
public BufferedImage Player(int x, int y) {
BufferedImage player = Sprite.getSprite(x, y);
return player;
}
public void update() {
animation.update();
}
public void render() {
}
public void setAnimation(Animation animation) {
this.animation = animation;
}
}
Sprite.Java:
package Sprites;
import Game.Game;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
public class Sprite {
public int w, h;
public int[] pixels;
public static BufferedImage sprite = null;
public Sprite(int w, int h) {
this.w = w;
this.h = h;
pixels = new int[w * h];
}
public void clear(int color) {
for(int i = 0; i < pixels.length; i++) {
pixels[i] = color;
}
}
private static BufferedImage spriteSheet;
private static final int TILE_SIZE = 80;
public static BufferedImage loadSprite() {
try {
sprite = ImageIO.read(Game.class.getResource("/valkyrie.png"));
} catch (IOException e) {
e.printStackTrace();
}
return sprite;
}
public static BufferedImage getSprite(int xGrid, int yGrid) {
if(spriteSheet == null) {
spriteSheet = loadSprite();
}
// xGrid and yGrid refer to each individual sprite
return spriteSheet.getSubimage(xGrid * TILE_SIZE, yGrid * TILE_SIZE, TILE_SIZE, TILE_SIZE);
}
}
This is going to require double buffering. Any game with a lot going on needs double buffering.
How do you double buffer in java for a game?
Although I couldn't go through the code completely, it seems you do not do double buffering which affect performance drastically.
Try this in the relevant part of your program:
JFrame frame = new JFrame("Valkyrie Game");
frame.add(game);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.pack();
frame.setResizable(true);
frame.setLocationRelativeTo(null);
frame.setVisible(true);
frame.setDoubleBuffered(true); //added line, rest is the same
game.start();
You really should use Timer. It will solve all your problems.
Every tick, you redraw all what you need.
And every tick, you should just check, which keys are pressed and which are not, instead of adding listeners. To keep tracking this, you always have to remember the keys pressed "before".
You can even create two Timers, one for graphic redraw and one for game logic.
Even timers can be delayed or something, the usual approach is to find out, how much time elapsed (System.nanoTime for example) and count how much of game logic you should forward to keep game always unlaggy and fluent.
I am making a tile based platformer game in java. I render a map which is stored in a 2 dimensional array but when this array is very big my game starts to become slow. I realised that I had to only render the part of the map that is viewable, I tried to do that but i wrote very hacky code that only worked partly so I removed it. How can I do this properly? Here is my code (without the hacky stuff). Also how could I use System.nanoTime() rather than System.currentTimeMillis()?
package sexy_robot_from_another_dimension;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.TexturePaint;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Timer;
import java.util.TimerTask;
import javax.swing.JPanel;
#SuppressWarnings("serial")
public class Game extends JPanel
{
int playerX = 50;
int playerY = 50;
static boolean up = false;
static boolean down = false;
static boolean right = false;
static boolean left = false;
int playerSpeed = 1;
String[][] map;
int blockSize = 20;
int jumpLoop = 0;
int maxJumpLoop = 280;
static BufferedImage block, player;
int playerWidth = 20;
int playerHeight = 35;
int cameraX = 0;
int cameraY = 0;
long nextSecond = System.currentTimeMillis() + 1000;
int frameInLastSecond = 0;
int framesInCurrentSecond = 0;
public Game()
{
super();
try
{
map = load("/maps/map1.txt");
}
catch (IOException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
Timer timer = new Timer();
TimerTask task = new TimerTask()
{
#Override
public void run()
{
if(up)
{
if((!playerIsOnBlock(playerX, playerY).equals("0")) || (!playerIsOnBlock(playerX + (playerWidth - 1), playerY).equals("0")))
{
timeToJump();
}
}
if(down)
{
}
if(right)
{
if((playerIsLeftBlock(playerX, playerY).equals("0")) && (playerIsLeftBlock(playerX, playerY + (playerHeight/2 - 1)).equals("0")) && (playerIsLeftBlock(playerX, playerY + (playerHeight - 1)).equals("0")))
{
playerX += playerSpeed;
}
}
if(left)
{
if((playerIsRightBlock(playerX, playerY).equals("0")) && (playerIsRightBlock(playerX, playerY + (playerHeight/2 - 1)).equals("0")) && (playerIsRightBlock(playerX, playerY + (playerHeight - 1)).equals("0")))
{
playerX -= playerSpeed;
}
}
repaint();
}
};
timer.scheduleAtFixedRate(task, 0, 10);
Timer timerGrav = new Timer();
TimerTask taskGrav = new TimerTask()
{
#Override
public void run()
{
if((playerIsOnBlock(playerX, playerY).equals("0")) && (playerIsOnBlock(playerX + (playerWidth - 1), playerY).equals("0")))
{
playerY += playerSpeed;
repaint();
}
}
};
timerGrav.scheduleAtFixedRate(taskGrav, 0, 6);
}
void timeToJump()
{
if(jumpLoop == 0)
{
jumpLoop = 1;
Timer timer = new Timer();
TimerTask task = new TimerTask()
{
#Override
public void run()
{
if((playerIsBelowBlock(playerX, playerY).equals("0")) && (playerIsBelowBlock(playerX + (playerWidth - 1), playerY).equals("0")))
{
playerY -= playerSpeed;
jumpLoop++;
repaint();
}
else
{
jumpLoop = maxJumpLoop;
}
if(jumpLoop == maxJumpLoop)
{
jumpLoop = 0;
cancel();
}
}
};
timer.scheduleAtFixedRate(task, 0, 3);
}
}
public void paintComponent(Graphics g)
{
super.paintComponent(g);
Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
long currentTime = System.currentTimeMillis();
if (currentTime > nextSecond)
{
nextSecond += 1000;
frameInLastSecond = framesInCurrentSecond;
framesInCurrentSecond = 0;
}
framesInCurrentSecond++;
g.drawString(frameInLastSecond + " fps", 10, 20);
cameraX = -playerX + getWidth()/2;
cameraY = -playerY + getHeight()/2;
g.translate(cameraX, cameraY);
for (int x = 0; x < map.length; x++)
{
for (int y = 0; y < map[0].length; y++)
{
switch(map[x][y])
{
case "0":
break;
case "1":
if(block != null)
{
TexturePaint tp0 = new TexturePaint(block, new Rectangle(0, 0, blockSize, blockSize));
g2.setPaint(tp0);
}
g.fillRect(y*blockSize, x*blockSize, 20, 20);
break;
}
}
}
g.setColor(Color.BLACK);
if(player != null)
{
TexturePaint tp0 = new TexturePaint(player, new Rectangle(playerX, playerY, playerWidth, playerHeight));
g2.setPaint(tp0);
}
g.fillRect(playerX, playerY, playerWidth, playerHeight);
g.setColor(Color.black);
g.setFont(new Font("Droid Sans Mono", Font.PLAIN, 12));
g.drawString("Sexy!", playerX - 5, playerY - 10);
}
boolean outOfMap(int x, int y)
{
y -= blockSize - 1;
x -= blockSize - 1;
if((y/blockSize <= map.length - 2) && (y/blockSize >= 0) && (x/blockSize <= map[0].length-2) && (x/blockSize >= 0))
{
return false;
}
return true;
}
String playerIsOnBlock(int x, int y)
{
y += playerHeight;
if(!outOfMap(x, y))
{
if(map[y/blockSize][x/blockSize] != "0")
{
return map[y/blockSize][x/blockSize];
}
}
return "0";
}
String playerIsBelowBlock(int x, int y)
{
y -= playerSpeed;
if(!outOfMap(x, y))
{
if(map[y/blockSize][x/blockSize] != "0")
{
return map[y/blockSize][x/blockSize];
}
}
return "0";
}
String playerIsLeftBlock(int x, int y)
{
x += playerWidth;
if(!outOfMap(x, y))
{
if(map[y/blockSize][x/blockSize] != "0")
{
return map[y/blockSize][x/blockSize];
}
}
return "0";
}
String playerIsRightBlock(int x, int y)
{
x -= playerSpeed;
if(!outOfMap(x, y))
{
if(map[y/blockSize][x/blockSize] != "0")
{
return map[y/blockSize][x/blockSize];
}
}
return "0";
}
String[][] load(String file) throws IOException
{
BufferedReader br = new BufferedReader(new InputStreamReader(getClass().getResourceAsStream(file)));
int lines = 1;
int length = br.readLine().split(" ").length;
while (br.readLine() != null) lines++;
br.close();
br = new BufferedReader(new InputStreamReader(getClass().getResourceAsStream(file)));
String[][] map = new String[lines][length];
for (int i = 0; i < lines; i++)
{
String line = br.readLine();
String[] parts = line.split(" ");
for (int y = 0; y < length; y++)
{
map[i][y] = parts[y];
}
}
br.close();
return map;
}
}
Thank you!
It seems your camera is centered on the player, then there are two ways of doing this, I like the first way, it is a bit cleaner:
1th: Create a rectangle that bounds your cameras view, and check if the map x,y is within this view, render only if true.
Rectangle cameraView = new Rectangle(playerX - getWidth() / 2, playerY - getHeight() / 2, getWidth(), getHeight());
for (int x = 0; x < map.length; x++) {
for (int y = 0; y < map[0].length; y++) {
if (!cameraView.contains(x*blockSize, y*blockSize))
continue;
switch (map[x][y]) {
case "0":
break;
case "1":
if (block != null) {
TexturePaint tp0 = new TexturePaint(block, new Rectangle(0, 0, blockSize, blockSize));
g2.setPaint(tp0);
}
g.fillRect(y * blockSize, x * blockSize, 20, 20);
break;
}
}
}
The second option is to simply calculate the distance to the center of the screen (playerX,playerY) from each map[x][y] and skip all map[x][y] that falls outside your viewing bounds, this is a bit uglier to code and I really don't recommend this, the rectangle option above should be fast enough.
Edit:
#JasonC That is true, I didn't consider for instance when an x value is definitely outside the view, it will still go into the y loop through all the y values. One can simply create a dummy variable in the x-loop and do the following check
for (int x = 0; x < map.length; x++) {
int dummyY = playerY
if(!cameraView.contains(x,dummyY))
continue;
....
//rest of code ommitted
Another optimization you can do is considering not setting a TexturePaint (expensive operation) but instead simply drawing the image of the block:
g.fillRect(y * blockSize, x * blockSize, 20, 20);
Replaced with
g.drawImage(block, y*blockSize, x*blockSize, null);
The same with the playerimage.
Set the clipping region to the visible area with Graphics.setClip(), that will prevent most rendering operations from taking effect outside that region.
For drawing operations where this isn't sufficient (perhaps you also want to avoid doing calculations or something for objects outside the clipping area), test your objects bounds against the clipping rectangle and skip the object if it doesn't intersect.
See Graphics.setClip().
A further optimization can be done by, for example, calculating the range of blocks on your map that is definitely outside of the visible area, and excluding that from your for loop (no sense testing blocks against the clipping region if you know they are outside already). Take the clipping region, transform it to map index coordinates, then you will know where in your map the visible area is and you can just iterate over that subsection of the map.
So I'm trying to implement collision detection in my game and for some reason the collision isnt working properly.
public class ArenaKeys extends KeyAdapter {
arenaScreenBuild arena;
int xPos = 0, playerFace = 4;
int xPPos = 200, yPPos = 150;
int pX = 40, pY = 30;
AttackAshe aAtk = new AttackAshe();
int[][] mask = new int[400][92];
#SuppressWarnings("static-access")
public void keyPressed(KeyEvent e) {
int keyCode = e.getKeyCode();// Get key pressed
if (keyCode == e.VK_RIGHT) {
playerFace = 4;
xPos += 5;
pX = (xPos + xPPos) / 5;
if (checkBoundary(pX, pY) == (false))
xPos -= 5;
} else if (keyCode == e.VK_LEFT) {
playerFace = 3;
xPos -= 5;
pX = (xPos + xPPos) / 5;
if (checkBoundary(pX, pY) == (false))
xPos += 5;
} else if (keyCode == e.VK_UP) {
playerFace = 2;
yPPos -= 5;
pY = yPPos / 5;
if (checkBoundary(pX, pY) == (false))
yPPos += 5;
} else if (keyCode == e.VK_DOWN) {
playerFace = 1;
yPPos += 5;
pY = yPPos / 5;
if (checkBoundary(pX, pY) == (false))
yPPos -= 5;
}
if (keyCode == e.VK_SPACE) {
aAtk.regArrow(arena.xPosition(), arena.yPosition());
arena.shoot(playerFace);
arena.xArrow = xPPos;
arena.yArrow = yPPos;
} else if (keyCode == e.VK_ESCAPE)
System.exit(0);
arena.moveArena(xPos);
arena.turnPlayer(playerFace);
arena.updateScreen(xPPos, yPPos);
}
public boolean checkBoundary(int x, int y) {
Rectangle t1 = new Rectangle(Turret.x, Turret.y, Turret.WIDTH,
Turret.HEIGHT);
Rectangle p = new Rectangle(pX, pY, Player.WIDTH, Player.HEIGHT);
if (t1.intersects(p))
// if (mask[x][y] == 0)
return false;
else
return true;
}
public static class Turret {
static int x = 168;
static int y = 40;
static final int WIDTH = 50;
static final int HEIGHT = 50;
}
public static class Player {
static final int WIDTH = 25;
static final int HEIGHT = 25;
}
public ArenaKeys(arenaScreenBuild arena) throws Exception {
this.arena = arena;
}
}
Approximately 20 units before the actual turret, the sprite stops being able to move any further. The sprite cannot go above or below the turret even if you go really high or really low.
What seems to be going wrong is that the sprite is colliding into the turret rectangle too early but I don't understand how that it possible. I draw the turret exactly 50 wide, 50 high at 168,40. The player is moving so it's x, y is different everytime but it's dimensions are 25 wide and 25 high.
The original turret is 126x111 approximately but I draw it as 50x50
25x25
public class arenaScreenBuild extends JPanel implements ActionListener {
String picPath = "pictures/";
String[] fileName = { "stageBridge.png", "turret.png", "Ashe.png",
"regArrow.png", "arenaScreen.png" };
ClassLoader cl = arenaScreenBuild.class.getClassLoader();
URL imgURL[] = new URL[5];
Toolkit tk = Toolkit.getDefaultToolkit();
Image imgBG, imgTurret, imgPlayer, imgRegArrow, imgBorder;
Boolean[] ptFunc = new Boolean[3];
int PLAYER_INITIAL_X = 200, PLAYER_INITIAL_Y = 150;
int xPos = 0, xPFace = 150, yPFace = 0;
int xPPos = 200, yPPos = 150;
int xVal, yVal, xArrow, yArrow, xTemp, yTemp;
Timer space;
int counter, facePosition = 1;
public arenaScreenBuild() throws Exception {
for (int x = 0; x < 5; x++) {
imgURL[x] = cl.getResource(picPath + fileName[x]);
}
imgBG = tk.createImage(imgURL[0]);
imgTurret = tk.createImage(imgURL[1]);
imgPlayer = tk.createImage(imgURL[2]);
imgRegArrow = tk.createImage(imgURL[3]);
imgBorder = tk.createImage(imgURL[4]);
for (int x = 0; x < 3; x++)
ptFunc[x] = true;
space = new Timer(100, this);
}
public void updateScreen() {
repaint();
}
public void moveArena(int x) {
xPos = x;
}
public void updateScreen(int x, int y) {
xPPos = x;
yPPos = y;
repaint();
}
public boolean arrow() {
return (true);
}
public void turnPlayer(int face) {
if (face == 4) {
xPFace = 150;
} else if (face == 3) {
xPFace = 100;
} else if (face == 2) {
xPFace = 50;
} else if (face == 1) {
xPFace = 0;
}
if (yPFace == 50)
yPFace = 0;
else if (yPFace == 0)
yPFace = 50;
}
public void paintComponent(Graphics g) {
g.drawImage(imgBG, 10, 30, 610, 490, xPos, 0, xPos + 600, 460, this);
g.drawImage(imgTurret, 850 - xPos, 200, 950 - xPos, 300, 0, 0, 126,
110, this);
g.drawImage(imgTurret, 1350 - xPos, 200, 1450 - xPos, 300, 0, 0, 126,
110, this);
g.drawImage(imgPlayer, xPPos, yPPos, 50 + (xPPos),
50 + (yPPos), xPFace, yPFace, xPFace + 50, yPFace + 50, this);
if (counter <= 5000 && counter > 0)
g.drawImage(imgRegArrow, xArrow, yArrow, this);
g.drawImage(imgBorder, 0, 0, 620, 600, 0, 0, 620, 600, this);
g.setColor(Color.WHITE);
g.drawString("x:" + (xPPos + xPos), 535, 525);
g.drawString("y:" + yPPos, 535, 545);
}
public int xPosition() {
xVal = xPPos + xPos;
return (xVal);
}
public int yPosition() {
yVal = yPPos;
return (yVal);
}
public void shoot(int i) {
facePosition = i;
xTemp = xPosition();
yTemp = yPosition();
space.start();
}
public void actionPerformed(ActionEvent e) {
counter++;
if (facePosition == 4) {
if (counter <= 5000) {
xArrow += 50;
}
}
else if (facePosition == 3) {
if (counter <= 5000) {
xArrow -= 50;
}
}
else if (facePosition == 2) {
if (counter <= 5000) {
yArrow -= 50;
}
}
else if (facePosition == 1) {
if (counter <= 5000) {
yArrow += 50;
}
}
if (xArrow == (xTemp + 100)) {
counter = 0;
space.stop();
}
updateScreen();
}
}
Turns out that my values for the x position were wrong. Also due to my previous boundary code, there were still remenants of it which messed me up therefore not allowing me to see the problem sooner.
For any one looking for how to make the collision detection boundary, just make 2 rectangles and use the
Rectangle rect1 = new Rectangle(topLeftX, topLeftY, rectangleWidth,rectangleHeight);
Rectangle rect2 = new Rectangle(topLeftX, topLeftY, rectangleWidth, rectangleHeight);
if (rect1.intersects(rect2))
//enter code to do if it intersects here