How to rotate a non-square image in Java?

Question

I recently saw this question on how to rotate an image in Java. I copy/pasted it directly from that answer. On implementation, it seems to only rotate images that are squares(that is have the same size, width and height). When I try to use it for a non-square image, it seems to cut off that part that would make it be a rectangle, if that makes sense. Like this How can I fix/work around this? Edit: The code I'm using. Also, I won't have a scroll bar as this will be a "game", and also won't be in full screen all of the time. ``` public class Player extends Entity { //Entity has basic values such as (float) x & y values, along with some getters and setters double theta; Reticle reticle; //draws a reticle where the cursor was(basically just replaces java.awt.Cursor due to something not neccessary for me to get into) Sprite currentImage; //basically just a BufferedImage that you can apply aspect ratios to //constructor @Override public void tick() { //(this line) gets the Reticle from the…

Accepted Answer

When you rotate an image the width and height also change and your code doesn't take this into account.

Here is some old code I have lying around that should work better:

```
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.event.*;

public class Rotation
{
    BufferedImage image;
    JLabel label;

public Rotation(BufferedImage image)
    {
        this.image = image;
    }

private BufferedImage getImage(double theta)
    {
        //  Determine the size of the rotated image

double cos = Math.abs(Math.cos(theta));
        double sin = Math.abs(Math.sin(theta));
        double width  = image.getWidth();
        double height = image.getHeight();
        int w = (int)(width * cos + height * sin);
        int h = (int)(width * sin + height * cos);

//  Rotate and paint the original image onto a BufferedImage

BufferedImage out = new BufferedImage(w, h, image.getType());
        Graphics2D g2 = out.createGraphics();
        g2.setPaint(UIManager.getColor("Panel.background"));
        g2.fillRect(0,0,w,h);
        double x = w/2;
        double y = h/2;
        AffineTransform at = AffineTransform.getRotateInstance(theta, x, y);
        x = (w - width)/2;
        y = (h - height)/2;
        at.translate(x, y);
        g2.drawRenderedImage(image, at);
        g2.dispose();
        return out;
    }

private JLabel getLabel()
    {
        ImageIcon icon = new ImageIcon(image);
        label = new JLabel(icon);
        label.setHorizontalAlignment(JLabel.CENTER);
        return label;
    }

private JSlider getSlider()
    {
        final JSlider slider = new JSlider(JSlider.HORIZONTAL, 0, 360, 0);
        slider.addChangeListener(new ChangeListener()
        {
            public void stateChanged(ChangeEvent e)
            {
                int value = slider.getValue();
                BufferedImage bi = getImage(Math.toRadians(value));
                label.setIcon(new ImageIcon(bi));
            }
        });
        return slider;
    }

public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                try
                {
                    String path = "mong.jpg";
                    ClassLoader cl = Rotation.class.getClassLoader();
                    BufferedImage bi = ImageIO.read(cl.getResourceAsStream(path));
                    Rotation r = new Rotation(bi);
                    JFrame f = new JFrame();
                    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    f.getContentPane().add(new JScrollPane(r.getLabel()));
                    f.getContentPane().add(r.getSlider(), "South");
                    f.pack();
                    f.setLocation(200,200);
                    f.setVisible(true);
                }
                catch(IOException e)
                {
                    System.out.println(e);
                }
            }
        });
    }
}
```

Edit:

Another option is to create an Icon, then you can use the Rotated Icon. Then you can rotate and paint the icon in your painting code. Something like:

```
import java.awt.*;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.IOException;
import javax.imageio.ImageIO;
import javax.swing.*;
import javax.swing.event.*;

public class Rotation3 extends JPanel
{
    private Icon icon;
    private Icon rotated;
    private int degrees;

public Rotation3(BufferedImage image)
    {
        icon = new ImageIcon( image );
        setDegrees( 0 );
        setPreferredSize( new Dimension(600, 600) );
    }

@Override
    protected void paintComponent(Graphics g)
    {
        super.paintComponent(g);

double radians = Math.toRadians( degrees );
        rotated = new RotatedIcon(icon, degrees);

// translate x/y so Icon is rotated around a specific point (300, 300)

int x = 300 - (rotated.getIconWidth() / 2);
        int y = 300 - (rotated.getIconHeight() / 2);
        rotated.paintIcon(this, g, x, y);

g.setColor(Color.RED);
        g.fillOval(295, 295, 10, 10);
    }

public void setDegrees(int degrees)
    {
        this.degrees = degrees;
        double radians = Math.toRadians( degrees );
        rotated = new RotatedIcon(icon, degrees);
        repaint();
    }

public static void main(String[] args)
    {
        EventQueue.invokeLater(new Runnable()
        {
            public void run()
            {
                try
                {
                    String path = "dukewavered.gif";
                    ClassLoader cl = Rotation3.class.getClassLoader();
                    BufferedImage bi = ImageIO.read(cl.getResourceAsStream(path));
                    final Rotation3 r = new Rotation3(bi);

final JSlider slid…

How to rotate a non-square image in Java?

Solution

Problem

Related problems