How to display different parts of an image

Question

hi,
I need to display different parts of an image at specific situations.
for example, a dice. there is only one image which includes different sides of the dice. and I wanna add
to my panel one side if one comes, two side if two comes... I mean if one comes then we will display
from 10 px to 80 px width and from 10 px to 80 px height of the dice image.
is there any way to obtain this in java?
thanks...

Answer 1

import java.awt.*;
import java.awt.font.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import java.util.Random;
import javax.swing.*;
public class ImageClipping extends JPanel {
    BufferedImage image;
    Rectangle clip;
    final int ROWS = 3;
    final int COLS = 3;
    public ImageClipping() {
        // Make an image we can clip.
        Dimension d = getPreferredSize();
        int type = BufferedImage.TYPE_INT_RGB;
        image = new BufferedImage(d.width, d.height, type);
        Graphics2D g2 = image.createGraphics();
        g2.setBackground(getBackground());
        g2.clearRect(0, 0, d.width, d.height);
        Font font = g2.getFont().deriveFont(36f);
        g2.setFont(font);
        FontRenderContext frc = g2.getFontRenderContext();
        LineMetrics lm = font.getLineMetrics("0", frc);
        float sh = lm.getAscent() + lm.getDescent();
        int xInc = d.width/COLS;
        int yInc = d.height/ROWS;
        for(int j = 0; j < ROWS; j++) {
            for(int k = 0; k < COLS; k++) {
                String s = String.valueOf(j*COLS + k+1);
                float sw = (float)font.getStringBounds(s, frc).getWidth();
                float sx = k*xInc + (xInc - sw)/2;
                float sy = j*yInc + (yInc + sh)/2 - lm.getDescent();
                g2.setPaint(Color.red);
                g2.drawString(s, sx, sy);
                g2.setPaint(Color.blue);
                g2.drawRect(k*xInc, j*yInc, xInc-1, yInc-1);
        g2.dispose();
        clip = new Rectangle(xInc, yInc);
        // Inspect image.
        ImageIcon icon = new ImageIcon(image);
        JOptionPane.showMessageDialog(null, icon, "", -1);
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D)g;
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                            RenderingHints.VALUE_ANTIALIAS_ON);
        Shape origClip = g2.getClip();
        //g2.setPaint(Color.red);
        //g2.draw(clip);
        // Draw clipped image at:
        int x = 100;
        int y = 100;
        // Mark location.
        g2.setPaint(Color.red);
        g2.fill(new Ellipse2D.Double(x-2,y-2,4,4));
        // Position the image.
        g2.translate(x-clip.x, y-clip.y);
        // Clip it and draw.
        g2.setClip(clip);
        g2.drawImage(image,0,0,this);
        // Reverse the changes to the graphics context.
        g2.setClip(origClip);
        g2.translate(clip.x-x, clip.y-y);
    public Dimension getPreferredSize() {
        return new Dimension(400,400);
    public static void main(String[] args) {
        ImageClipping test = new ImageClipping();
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.add(test);
        f.pack();
        f.setLocation(50,50);
        f.setVisible(true);
        test.start();
    private void start() {
        Thread thread = new Thread(runner);
        thread.setPriority(Thread.NORM_PRIORITY);
        thread.start();
    private Runnable runner = new Runnable() {
        Random seed = new Random();
        Dimension d = getPreferredSize();
        int xInc = d.width/COLS;
        int yInc = d.height/ROWS;
        public void run() {
            do {
                try {
                    Thread.sleep(3000);
                } catch(InterruptedException e) {
                    break;
                int row = seed.nextInt(ROWS);
                int col = seed.nextInt(COLS);
                int x = col*xInc;
                int y = row*yInc;
                int n = row*COLS + col+1;
                System.out.printf("row = %d  col = %d  n = %d%n",
                                   row, col, n);
                clip.setLocation(x,y);
                repaint();
            } while(isVisible());
}