Java Tutorial/2D Graphics/Tranformation

Calculate Rotation Transform with Math.PI

   <source lang="java">

import java.awt.Canvas; import java.awt.Font; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Image; import java.awt.Toolkit; import java.awt.geom.AffineTransform; import java.awt.geom.Line2D; import javax.swing.JFrame; public class Draw2DRotate extends JFrame {

 public static void main(String args[]) {
   Draw2DRotate app = new Draw2DRotate();
 }
 public Draw2DRotate() {
   add("Center", new MyCanvas());
   setSize(400, 400);
   setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   setVisible(true);
 }

} class MyCanvas extends Canvas {

 public void paint(Graphics graphics) {
   Graphics2D g = (Graphics2D) graphics;
   AffineTransform transform = AffineTransform.getRotateInstance(Math.PI / 16.0d);
   g.setTransform(transform);
   Line2D.Double shape = new Line2D.Double(0.0, 0.0, 300.0, 300.0);
   g.draw(shape);
   g.setFont(new Font("Helvetica", Font.BOLD, 24));
   String text = ("jexp");
   g.drawString(text, 300, 50);
   Toolkit toolkit = Toolkit.getDefaultToolkit();
   Image image = toolkit.getImage("image1.gif");
   g.drawImage(image, 100, 150, this);
 }

}</source>

Coordinate Translation.

   <source lang="java">

import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import javax.swing.JFrame; import javax.swing.JPanel; public class Translation extends JPanel {

 public void paint(Graphics g) {
   super.paint(g);
   Graphics2D g2d = (Graphics2D) g;
   g2d.setColor(new Color(150, 150, 150));
   g2d.fillRect(20, 20, 80, 50);
   g2d.translate(150, 50);
   g2d.fillRect(20, 20, 80, 50);
 }
 public static void main(String[] args) {
   JFrame frame = new JFrame("Translation");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.add(new Translation());
   frame.setSize(300, 200);
   frame.setVisible(true);
 }

}</source>

Move and scale graphical objects with a mouse on the panel

   <source lang="java">

import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import java.awt.event.MouseWheelEvent; import java.awt.event.MouseWheelListener; import java.awt.geom.Rectangle2D; import javax.swing.JFrame; import javax.swing.JPanel; public class MouseMoveScale extends JPanel {

 private Rectangle2D.Float myRect = new Rectangle2D.Float(50, 50, 50, 50);
 MovingAdapter ma = new MovingAdapter();
 public MouseMoveScale() {
   addMouseMotionListener(ma);
   addMouseListener(ma);
   addMouseWheelListener(new ScaleHandler());
 }
 public void paint(Graphics g) {
   super.paint(g);
   Graphics2D g2d = (Graphics2D) g;
   g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
   g2d.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
       RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
   g2d.setColor(new Color(0, 0, 200));
   g2d.fill(myRect);
 }
 class MovingAdapter extends MouseAdapter {
   private int x;
   private int y;
   public void mousePressed(MouseEvent e) {
     x = e.getX();
     y = e.getY();
   }
   public void mouseDragged(MouseEvent e) {
     int dx = e.getX() - x;
     int dy = e.getY() - y;
     if (myRect.getBounds2D().contains(x, y)) {
       myRect.x += dx;
       myRect.y += dy;
       repaint();
     }
     x += dx;
     y += dy;
   }
 }
 class ScaleHandler implements MouseWheelListener {
   public void mouseWheelMoved(MouseWheelEvent e) {
     int x = e.getX();
     int y = e.getY();
     if (e.getScrollType() == MouseWheelEvent.WHEEL_UNIT_SCROLL) {
       if (myRect.getBounds2D().contains(x, y)) {
         float amount = e.getWheelRotation() * 5f;
         myRect.width += amount;
         myRect.height += amount;
         repaint();
       }
     }
   }
 }
 public static void main(String[] args) {
   JFrame frame = new JFrame("Moving and Scaling");
   MouseMoveScale m = new MouseMoveScale();
   m.setDoubleBuffered(true);
   frame.add(m);
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.setSize(300, 300);
   frame.setLocationRelativeTo(null);
   frame.setVisible(true);
 }

}</source>

Rotate a line of character (String)

   <source lang="java">

import java.awt.Font; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.RenderingHints; import java.awt.Shape; import java.awt.font.FontRenderContext; import java.awt.font.GlyphVector; import java.awt.geom.AffineTransform; import java.awt.geom.Point2D; import javax.swing.JFrame; import javax.swing.JPanel; public class RotatedText extends JPanel {

 public void paint(Graphics g) {
   Graphics2D g2d = (Graphics2D) g;
   g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
   String s = "111111111111111111111111111111";
   Font font = new Font("Courier", Font.PLAIN, 12);
   g2d.translate(20, 20);
   FontRenderContext frc = g2d.getFontRenderContext();
   GlyphVector gv = font.createGlyphVector(frc, s);
   int length = gv.getNumGlyphs();
   for (int i = 0; i < length; i++) {
     Point2D p = gv.getGlyphPosition(i);
     AffineTransform at = AffineTransform.getTranslateInstance(p.getX(), p.getY());
     at.rotate((double) i / (double) (length - 1) * Math.PI / 3);
     Shape glyph = gv.getGlyphOutline(i);
     Shape transformedGlyph = at.createTransformedShape(glyph);
     g2d.fill(transformedGlyph);
   }
 }
 public static void main(String[] args) {
   JFrame frame = new JFrame("Rotated text");
   frame.add(new RotatedText());
   frame.setSize(400, 300);
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.setLocationRelativeTo(null);
   frame.setVisible(true);
 }

}</source>

Rotates a shape about the specified coordinates.

   <source lang="java">

/*

* JCommon : a free general purpose class library for the Java(tm) platform
* 
*
* (C) Copyright 2000-2008, by Object Refinery Limited and Contributors.
*
* Project Info:  http://www.jfree.org/jcommon/index.html
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* -------------------
* ShapeUtilities.java
* -------------------
* (C)opyright 2003-2008, by Object Refinery Limited and Contributors.
*
* Original Author:  David Gilbert (for Object Refinery Limited);
* Contributor(s):   -;
*
* $Id: ShapeUtilities.java,v 1.18 2008/06/02 06:58:28 mungady Exp $
*
* Changes
* -------
* 13-Aug-2003 : Version 1 (DG);
* 16-Mar-2004 : Moved rotateShape() from RefineryUtilities.java to here (DG);
* 13-May-2004 : Added new shape creation methods (DG);
* 30-Sep-2004 : Added createLineRegion() method (DG);
*               Moved drawRotatedShape() method from RefineryUtilities class
*               to this class (DG);
* 04-Oct-2004 : Renamed ShapeUtils --> ShapeUtilities (DG);
* 26-Oct-2004 : Added a method to test the equality of two Line2D
*               instances (DG);
* 10-Nov-2004 : Added new translateShape() and equal(Ellipse2D, Ellipse2D)
*               methods (DG);
* 11-Nov-2004 : Renamed translateShape() --> createTranslatedShape() (DG);
* 07-Jan-2005 : Minor Javadoc fix (DG);
* 11-Jan-2005 : Removed deprecated code in preparation for 1.0.0 release (DG);
* 21-Jan-2005 : Modified return type of RectangleAnchor.coordinates()
*               method (DG);
* 22-Feb-2005 : Added equality tests for Arc2D and GeneralPath (DG);
* 16-Mar-2005 : Fixed bug where equal(Shape, Shape) fails for two Polygon
*               instances (DG);
* 01-Jun-2008 : Fixed bug in equal(GeneralPath, GeneralPath) method (DG);
*
*/

import java.awt.Shape; import java.awt.geom.AffineTransform; import java.awt.geom.Point2D; /**

* Utility methods for {@link Shape} objects.
*
* @author David Gilbert
*/

public class Main {

 /**
  * Rotates a shape about the specified coordinates.
  *
  * @param base  the shape (null permitted, returns
  *              null).
  * @param angle  the angle (in radians).
  * @param x  the x coordinate for the rotation point (in Java2D space).
  * @param y  the y coordinate for the rotation point (in Java2D space).
  *
  * @return the rotated shape.
  */
 public static Shape rotateShape(final Shape base, final double angle,
                                 final float x, final float y) {
     if (base == null) {
         return null;
     }
     final AffineTransform rotate = AffineTransform.getRotateInstance(
             angle, x, y);
     final Shape result = rotate.createTransformedShape(base);
     return result;
 }

}</source>

Rotating image using Java 2D AffineTransform class

   <source lang="java">

import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.Image; import java.awt.Rectangle; import java.awt.geom.AffineTransform; import javax.swing.JPanel; class ImagePanel extends JPanel {

 int offset = 5;
 private Image image;
 private int angle;
 private int w, h;
 private AffineTransform transform;
 public ImagePanel(Image i) {
   image = i;
   w = image.getWidth(this);
   h = image.getHeight(this);
   transform = new AffineTransform();
 }
 public void paintComponent(Graphics grp) {
   Rectangle rect = this.getBounds();
   Graphics2D g2d = (Graphics2D) grp;
   transform.setToTranslation((rect.width - w) / 2,
       (rect.height - h) / 2);
   transform.rotate(Math.toRadians(angle), w / 2,
       h / 2);
   g2d.drawImage(image, transform, this);
 }
 public void rotate() {
   angle -= offset;
   if (angle <= 0) {
     angle = 360;
   }
   repaint();
 }

}</source>

Rotation and coordinate translation

   <source lang="java">

import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import javax.swing.JFrame; import javax.swing.JPanel; public class Rotate extends JPanel {

 public void paint(Graphics g) {
   super.paint(g);
   Graphics2D g2d = (Graphics2D) g;
   g2d.setColor(new Color(150, 150, 150));
   g2d.fillRect(20, 20, 80, 50);
   g2d.translate(180, -150);
   g2d.rotate(Math.PI / 4);
   g2d.fillRect(20, 20, 80, 50);
 }
 public static void main(String[] args) {
   JFrame frame = new JFrame("Rotation");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.add(new Rotate());
   frame.setSize(300, 200);
   frame.setVisible(true);
 }

}</source>

Scaling an object

   <source lang="java">

import java.awt.Color; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; import javax.swing.JFrame; import javax.swing.JPanel; public class Scale extends JPanel {

 public void paint(Graphics g) {
   super.paint(g);
   Graphics2D g2d = (Graphics2D) g;
   g2d.setColor(new Color(150, 150, 150));
   g2d.fillRect(0, 0, 80, 50);
   AffineTransform tx1 = new AffineTransform();
   tx1.translate(110, 20);
   tx1.scale(0.5, 0.5);
   g2d.setTransform(tx1);
   g2d.fillRect(0, 0, 80, 50);
   AffineTransform tx2 = new AffineTransform();
   tx2.translate(200, 20);
   tx2.scale(1.5, 1.5);
   g2d.setTransform(tx2);
   g2d.fillRect(0, 0, 80, 50);
 }
 public static void main(String[] args) {
   JFrame frame = new JFrame("Scaling");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   frame.add(new Scale());
   frame.setSize(330, 160);
   frame.setLocationRelativeTo(null);
   frame.setVisible(true);
 }

}</source>

Tranformation with AffineTransform.getScaleInstance

   <source lang="java">

import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; public class AffineTransformGetScaleInstance extends Frame {

 public static void main(String[] args) {
   (new AffineTransformGetScaleInstance()).setVisible(true);
 }
 public AffineTransformGetScaleInstance() {
   setSize(350, 300);
 }
 public void paint(Graphics g) {
   AffineTransform atrans = null;
   Graphics2D g2d = (Graphics2D) g;
   atrans = AffineTransform.getScaleInstance(2, 3);
   if (atrans != null)
     g2d.setTransform(atrans);
   g2d.fillRect(50, 50, 100, 50);
 }

}</source>

Tranformation with AffineTransform.getShearInstance

   <source lang="java">

import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; public class AffineTransformGetShearInstance extends Frame {

 public static void main(String[] args) {
   (new AffineTransformGetShearInstance()).setVisible(true);
 }
 public AffineTransformGetShearInstance() {
   setSize(350, 300);
 }
 public void paint(Graphics g) {
   AffineTransform atrans = null;
   Graphics2D g2d = (Graphics2D) g;
   atrans = AffineTransform.getShearInstance(.1, .5);
   if (atrans != null)
     g2d.setTransform(atrans);
   g2d.fillRect(50, 50, 100, 50);
 }

}</source>

Tranformation with AffineTransform.getTranslateInstance

   <source lang="java">

import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; public class AffineTransformGetTranslateInstance extends Frame {

 public static void main(String[] args) {
   (new AffineTransformGetTranslateInstance()).setVisible(true);
 }
 public AffineTransformGetTranslateInstance() {
   setSize(350, 300);
 }
 public void paint(Graphics g) {
   AffineTransform atrans = null;
   Graphics2D g2d = (Graphics2D) g;
   atrans = AffineTransform.getTranslateInstance(50, 100);
   if (atrans != null)
     g2d.setTransform(atrans);
   g2d.fillRect(50, 50, 100, 50);
 }

}</source>

Transform Lab

   <source lang="java">

import java.awt.Frame; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.geom.AffineTransform; public class AffineTransformGetRotateInstance extends Frame {

 public static void main(String[] args) {
   (new AffineTransformGetRotateInstance()).setVisible(true);
 }
 public AffineTransformGetRotateInstance() {
   setSize(350, 300);
 }
 public void paint(Graphics g) {
   AffineTransform atrans = null;
   Graphics2D g2d = (Graphics2D) g;
   atrans = AffineTransform.getRotateInstance(Math.PI / 4, 50, 50);
   if (atrans != null)
     g2d.setTransform(atrans);
   g2d.fillRect(50, 50, 100, 50);
 }

}</source>

Translate and rotate all objects

   <source lang="java">

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);
 }

}</source>