java left logo
java middle logo
java right logo
 

Home arrow Other API Tips
 
 
Main Menu
Home
Java Tutorials
Book Reviews
Java SE Tips
Java ME Tips
Java EE Tips
Other API Tips
Java Applications
Java Libraries
Java Games
Java Network
Java Forums
Java Blog




Most Visited Tips
Java SE Tips
Java ME Tips
Java EE Tips
Other API Tips
Java Applications
Java Libraries
Java Games
Book Reviews
Top Rated Tips
Java SE Tips
Java ME Tips
Java EE Tips
Other API Tips
Java Applications
Java Libraries
Java Games
Book Reviews


Statistics
Registered Users: 3899
Java SE Tips: 614
Java ME Tips: 202
Java EE Tips: 183
Other API Tips: 779
Java Applications: 298
Java Libraries: 209
Java Games: 16
Book Reviews:
 
 
 
Animation and interaction of a Bouncing Ball E-mail
User Rating: / 10
PoorBest 

To create animation you need to move the objects between each frame of animation. You can use a timer and move the 3D objects by a small amount each time. Also, you can modify the objects in other ways, the next example scales the ball so that it looks squashed at the bottom of each bounce.

For interaction with the user, you can process keystrokes or clicks on buttons or other components.

One thing to notice is that you have to tell Java3D you are going to move something by setting a capability. Otherwise, you will not be able to move anything once it has been drawn.

 objTrans = new TransformGroup();
 objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);

The following example combines these techniques. You start it by clicking on the button, then the ball bounces up and down, and you can press a or s to move the ball left or right.


Image

import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.GraphicsConfiguration;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.DirectionalLight;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.swing.Timer;
import javax.vecmath.Color3f;
import javax.vecmath.Point3d;
import javax.vecmath.Vector3d;
import javax.vecmath.Vector3f;

import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.Sphere;
import com.sun.j3d.utils.universe.SimpleUniverse;

public class BouncingBall extends Applet implements ActionListener, KeyListener {
  private Button go = new Button("Go");

  private TransformGroup objTrans;

  private Transform3D trans = new Transform3D();

  private float height = 0.0f;

  private float sign = 1.0f// going up or down

  private Timer timer;

  private float xloc = 0.0f;

  public BranchGroup createSceneGraph() {
    // Create the root of the branch graph
    BranchGroup objRoot = new BranchGroup();
    objTrans = new TransformGroup();
    objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    objRoot.addChild(objTrans);

    // Create a simple shape leaf node, add it to the scene graph.
    Sphere sphere = new Sphere(0.25f);
    objTrans = new TransformGroup();
    objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    Transform3D pos1 = new Transform3D();
    pos1.setTranslation(new Vector3f(0.0f0.0f0.0f));
    objTrans.setTransform(pos1);
    objTrans.addChild(sphere);
    objRoot.addChild(objTrans);
    BoundingSphere bounds = new BoundingSphere(new Point3d(0.00.00.0),
        100.0);

    Color3f light1Color = new Color3f(1.0f0.0f0.2f);
    Vector3f light1Direction = new Vector3f(4.0f, -7.0f, -12.0f);
    DirectionalLight light1 = new DirectionalLight(light1Color,
        light1Direction);
    light1.setInfluencingBounds(bounds);
    objRoot.addChild(light1);

    // Set up the ambient light
    Color3f ambientColor = new Color3f(1.0f1.0f1.0f);
    AmbientLight ambientLightNode = new AmbientLight(ambientColor);
    ambientLightNode.setInfluencingBounds(bounds);
    objRoot.addChild(ambientLightNode);

    return objRoot;
  }

  public BouncingBall() {
    setLayout(new BorderLayout());
    GraphicsConfiguration config = SimpleUniverse
        .getPreferredConfiguration();
    Canvas3D c = new Canvas3D(config);
    add("Center", c);
    c.addKeyListener(this);
    timer = new Timer(100this);
    //timer.start();
    Panel p = new Panel();
    p.add(go);
    add("North", p);
    go.addActionListener(this);
    go.addKeyListener(this);
    // Create a simple scene and attach it to the virtual universe
    BranchGroup scene = createSceneGraph();

    SimpleUniverse u = new SimpleUniverse(c);
    u.getViewingPlatform().setNominalViewingTransform();
    u.addBranchGraph(scene);
  }

  public void keyPressed(KeyEvent e) {
    //Invoked when a key has been pressed.
    if (e.getKeyChar() == 's') {
      xloc = xloc + .1f;
    }
    if (e.getKeyChar() == 'a') {
      xloc = xloc - .1f;
    }
  }

  public void keyReleased(KeyEvent e) {
    // Invoked when a key has been released.
  }

  public void keyTyped(KeyEvent e) {
    //Invoked when a key has been typed.
  }

  public void actionPerformed(ActionEvent e) {
    // start timer when button is pressed
    if (e.getSource() == go) {
      if (!timer.isRunning()) {
        timer.start();
      }
    else {
      height += .1 * sign;
      if (Math.abs(height * 2>= 1)
        sign = -1.0f * sign;
      if (height < -0.4f) {
        trans.setScale(new Vector3d(1.0.81.0));
      else {
        trans.setScale(new Vector3d(1.01.01.0));
      }
      trans.setTranslation(new Vector3f(xloc, height, 0.0f));
      objTrans.setTransform(trans);
    }
  }

  public static void main(String[] args) {
    System.out.println("Program Started");
    BouncingBall bb = new BouncingBall();
    bb.addKeyListener(bb);
    MainFrame mf = new MainFrame(bb, 256256);
  }
}

 Related Tips

 
< Prev   Next >

Page 1 of 0 ( 0 comments )

You can share your information about this topic using the form below!

Please do not post your questions with this form! Thanks.


Name (required)


E-Mail (required)

Your email will not be displayed on the site - only to our administrator
Homepage(optional)



Comment Enable HTML code : Yes No



 
       
         
     
 
 
 
   
 
 
java bottom left
java bottom middle
java bottom right
RSS 0.91 FeedRSS 1.0 FeedRSS 2.0 FeedATOM FeedOPML Feed

Home - About Us - Privacy Policy
Copyright 2005 - 2008 www.java-tips.org
Java is a trademark of Sun Microsystems, Inc.