i have found the way to make the Background permanent, by first creating it into a Buffered image, then on each action, repaint that image, without redraw all the primitive forms or the image rotations. I mean, first, i create the Background rotating a basic image multiple times. This is created using a Buffered image. Then, on the paintComponent() method, i redraw the buffered image:
public MyPanel(){
try {
image = ImageIO.read(url1);
image2 = ImageIO.read(url2);
image3 = ImageIO.read(url3);
} catch (IOException e) {
}
img = createImage();
}
private Image createImage(){
double index = 0;
BufferedImage bufferedImage = new BufferedImage(370,370,BufferedImage.TYPE_INT_ARGB);
Graphics g = bufferedImage.getGraphics();
for(index = 0; index <= scale; index = index + count){
tx = AffineTransform.getRotateInstance(Math.toRadians(deg2), 185, 185);
op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
g.drawImage(op.filter(image3, null), 0, 0, null);
deg2 = deg2 + (270.0/(scale/count));
}
return bufferedImage;
}
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.drawImage(image, 0, 0, null); //Indicator drawing
g.drawImage(img, 0, 0, null); //Scale drawing
//Indicator rotation
tx = AffineTransform.getRotateInstance(Math.toRadians(degrees), this.getHeight()/2, this.getWidth()/2);
op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
g.drawImage(op.filter(image2, null), 0, 0, null);
}
Here the complete code for a basic example:
package rotateOnImage;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Image;
import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JButton;
import javax.swing.AbstractAction;
import java.awt.event.ActionEvent;
import java.awt.geom.AffineTransform;
import java.awt.image.AffineTransformOp;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.URL;
import javax.swing.Action;
public class MainFrame extends JFrame {
/**
*
*/
private static final long serialVersionUID = 1L;
private JPanel contentPane;
private MyPanel panel = new MyPanel();
private final Action upAction = new upAction();
private final Action dnAction = new dnAction();
/**
* Launch the application.
*/
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
public void run() {
try {
MainFrame frame = new MainFrame();
frame.setVisible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
/**
* Create the frame.
*/
public MainFrame() {
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 345, 227);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
JButton btnNewButton = new JButton("UP");
btnNewButton.setAction(upAction);
btnNewButton.setBounds(212, 12, 117, 25);
contentPane.add(btnNewButton);
JButton button = new JButton("DN");
button.setAction(dnAction);
button.setBounds(212, 49, 117, 25);
contentPane.add(button);
panel.setBounds(0, 0, 200, 200);
contentPane.add(panel);
}
private class upAction extends AbstractAction {
/**
*
*/
private static final long serialVersionUID = 1L;
public upAction() {
putValue(NAME, "UP");
}
public void actionPerformed(ActionEvent e) {
panel.up();
}
}
private class dnAction extends AbstractAction {
/**
*
*/
private static final long serialVersionUID = 1L;
public dnAction() {
putValue(NAME, "DN");
}
public void actionPerformed(ActionEvent e) {
panel.down();
}
}
}
class MyPanel extends JPanel{
private static final long serialVersionUID = 1L;
/**
*
*/
private int degrees = 0;
private AffineTransform tx = null;
private AffineTransformOp op = null;
private BufferedImage image1 = null;
private BufferedImage image2 = null;
private BufferedImage image3 = null;
Image img = null;
public static final String IMAGE_PATH1 = "http://1.bp.blogspot.com/"+"-fq-oPGBSLp4/Ttoj7DoAMWI/AAAAAAAABtc/t7gKJlfRQuo/s400/secondHand.png";
public static final String IMAGE_PATH2 = "http://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/Circle_Fulvous_Solid.svg/200px-Circle_Fulvous_Solid.svg.png";
public static final String IMAGE_PATH3 ="http://www.xtremeskater.com/math/images/circle_radius.png";
public MyPanel(){
try {
URL url1 = new URL(IMAGE_PATH1);
URL url2 = new URL(IMAGE_PATH2);
URL url3 = new URL(IMAGE_PATH3);
image1 = ImageIO.read(url1);
image2 = ImageIO.read(url2);
image3 = ImageIO.read(url3);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
img = createImage();
}
public void up(){
degrees ++;
if(degrees == 360) degrees = 0;
repaint();
}
public void down(){
degrees --;
if(degrees == -360) degrees = 0;
repaint();
}
public int getDregrees(){
return degrees;
}
private Image createImage(){
double index = 0.0;
BufferedImage bufferedImage = new BufferedImage(200,200,BufferedImage.TYPE_INT_ARGB);
Graphics g = bufferedImage.getGraphics();
for(index = 0.0; index <= 36; index ++){
tx = AffineTransform.getRotateInstance(Math.toRadians(index*10), 100, 100);
op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
g.drawImage(op.filter(image3, null), 0, 0, null);
}
return bufferedImage;
}
public void update(Graphics g){
paint(g);
}
protected void paintComponent(Graphics g){
super.paintComponent(g);
g.drawImage(image2, 0, 0, null); //Dibujado de la manecilla
g.drawImage(img, 0, 0, null); //Dibujado de la escala
//Rotación de la manecilla
tx = AffineTransform.getRotateInstance(Math.toRadians(degrees), this.getHeight()/2, this.getWidth()/2);
op = new AffineTransformOp(tx, AffineTransformOp.TYPE_BILINEAR);
g.drawImage(op.filter(image1, null), 0, 0, null);
}
}
