Translate and rotate all objects : Tranformation « 2D Graphics « Java Tutorial

1. Java Tutorial
2. 2D Graphics
3. Tranformation

import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.GradientPaint;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.RenderingHints;
import java.awt.Shape;
import java.awt.Toolkit;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.awt.geom.RoundRectangle2D;

import javax.swing.JComponent;
import javax.swing.JFrame;

public class Main extends JComponent {
  private Image image;

  private int theta;

  public Main() {
    image = Toolkit.getDefaultToolkit().getImage("A.jpg");
    theta = 0;
    addMouseListener(new MouseAdapter() {
      public void mousePressed(MouseEvent me) {
        theta = (theta + 15) % 360;
        repaint();
      }
    });
  }

  public void paint(Graphics g) {
    Graphics2D g2 = (Graphics2D) g;

    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

    int cx = getSize().width / 2;
    int cy = getSize().height / 2;

    g2.translate(cx, cy);
    g2.rotate(theta * Math.PI / 180);

    Shape oldClip = g2.getClip();
    Shape e = new Ellipse2D.Float(-cx, -cy, cx * 2, cy * 2);
    g2.clip(e);

    Shape c = new Ellipse2D.Float(-cx, -cy, cx * 3 / 4, cy * 2);
    g2.setPaint(new GradientPaint(40, 40, Color.blue, 60, 50, Color.white, true));
    g2.fill(c);

    g2.setPaint(Color.yellow);
    g2.fillOval(cx / 4, 0, cx, cy);

    g2.setClip(oldClip);

    g2.setFont(new Font("Times New Roman", Font.PLAIN, 64));
    g2.setPaint(new GradientPaint(-cx, 0, Color.red, cx, 0, Color.black, false));
    g2.drawString("Hello, 2D!", -cx * 3 / 4, cy / 4);

    AlphaComposite ac = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, (float) .75);
    g2.setComposite(ac);

    Shape r = new RoundRectangle2D.Float(0, -cy * 3 / 4, cx * 3 / 4, cy * 3 / 4, 20, 20);
    g2.setStroke(new BasicStroke(4));
    g2.setPaint(Color.magenta);
    g2.fill(r);
    g2.setPaint(Color.green);
    g2.draw(r);

    g2.drawImage(image, -cx / 2, -cy / 2, this);
  }

  public static void main(String[] args) {
    JFrame frame = new JFrame();

    frame.add(new Main(), BorderLayout.CENTER);
    frame.setSize(300, 300);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
  }
}

16.3.Tranformation
	16.3.1.	Transform Lab
	16.3.2.	Coordinate Translation.
	16.3.3.	Rotation and coordinate translation
	16.3.4.	Rotate a line of character (String)
	16.3.5.	Scaling an object
	16.3.6.	Tranformation with AffineTransform.getScaleInstance
	16.3.7.	Tranformation with AffineTransform.getTranslateInstance
	16.3.8.	Tranformation with AffineTransform.getShearInstance
	16.3.9.	Calculate Rotation Transform with Math.PI
	16.3.10.	Rotating image using Java 2D AffineTransform class
	16.3.11.	Translate and rotate all objects
	16.3.12.	Move and scale graphical objects with a mouse on the panel
	16.3.13.	Rotates a shape about the specified coordinates.