Image is not rotating

Question

I am trying to rotate an image, somewhat it works but the problem is that it is not working properly. It's not rotating at exact I want. Image is displaying in some mix formation.

My code on button click :

RT90.addActionListener(new ActionListener() 
        {           
            @Override
            public void actionPerformed(ActionEvent arg0) 
            {
                degrees+=90;
                rotateIMG(degrees);
                repaint();
            }
        }); 

rotateIMG() code :

public void rotateIMG(double d)
    {
        BufferedImage b ;
        b=a;
        Graphics g;
        g=b.createGraphics();
        Graphics2D g2d = (Graphics2D)g;

        System.out.println(b.getWidth());
        System.out.println(b.getHeight());

        g2d.rotate(Math.toRadians(d), b.getWidth()/2, b.getHeight()/2);
        g2d.drawImage(b,0,0,null);

        ImageIcon rtimg = new ImageIcon(b);
        label.setIcon(rtimg);

    }

Any idea what's wrong in this code? Here a is buffered image which is loaded from image stack and label is JLabel using to display image.

Answer 1

You are overwriting the image you use as the source (b == a). You need to create a new instead.

public void rotateIMG(double d) {
    // Consider also using GraphicsConfiguration.createCompatibleImage().
    // I'm just putting here something that should work
    BufferedImage b = new BufferedImage(a.getHeight(), a.getWidth(), BufferedImage.TYPE_INT_ARGB);
    Graphics2D g2d = b.createGraphics();

    g2d.rotate(Math.toRadians(d), a.getWidth()/2, a.getHeight()/2);
    // Note the a instead of b here
    g2d.drawImage(a, 0, 0, null);
    // Do you want to keep the old a or not?
    // a = b;
    ImageIcon rtimg = new ImageIcon(b);
    label.setIcon(rtimg);
}

Answer 2

the problem is that some portion of image is cropped

Check out Rotated Icon. It will calculate the correct size of the Icon as it is rotated at various degrees.