Java 3D SimpleSounds Example

[Brendan Cregan]

Hi,

I have been trying to mess around with Java 3D, in particular the 3D sound engine, I found this example code for a SimpleSounds Applet and im getting compiling errors with the example code, I was just wondering does anyone have any experience with this example and how to get it working?

So the error is

Exception in thread "main" java.lang.NullPointerException: Canvas3D: null GraphicsConfiguration
at javax.media.j3d.Canvas3D.checkForValidGraphicsConfig(Canvas3D.java:963)
at javax.media.j3d.Canvas3D.<init>(Canvas3D.java:1006)
at SimpleSounds.<init>(SimpleSounds.java:47)
at SimpleSounds.main(SimpleSounds.java:249)

And the example code is

import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Frame;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.Appearance;
import javax.media.j3d.BackgroundSound;
import javax.media.j3d.BoundingLeaf;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.DirectionalLight;
import javax.media.j3d.Locale;
import javax.media.j3d.Material;
import javax.media.j3d.MediaContainer;
import javax.media.j3d.PhysicalBody;
import javax.media.j3d.PhysicalEnvironment;
import javax.media.j3d.PointSound;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.media.j3d.View;
import javax.media.j3d.ViewPlatform;
import javax.media.j3d.VirtualUniverse;
import javax.vecmath.Color3f;
import javax.vecmath.Point2f;
import javax.vecmath.Point3d;
import javax.vecmath.Point3f;
import javax.vecmath.Vector3f;

import com.sun.j3d.audioengines.javasound.JavaSoundMixer;
import com.sun.j3d.utils.behaviors.keyboard.KeyNavigatorBehavior;
import com.sun.j3d.utils.geometry.Box;

/**
 * This application demonstrates the use of 3D sound. It loads three sounds:
 * loop3.wav is an ambient background sound and loop1.wav and loop2.wav are
 * point sounds. The two point sounds can be switched on and off use AWT
 * buttons. The user can navigate around the scene using the keyboard.
 * 
 * @author I.J.Palmer
 * @version 1.0
 */
public class SimpleSounds extends Frame implements ActionListener {
  protected Canvas3D myCanvas3D = new Canvas3D(null);

  /** The exit button to quit the application */
  protected Button exitButton = new Button("Exit");

  /** The button to switch on and off the first sound */
  protected Button sound1Button = new Button("Sound 1");

  /** The button to switch on and off the second sound */
  protected Button sound2Button = new Button("Sound 2");

  protected BoundingSphere bounds = new BoundingSphere(new Point3d(0.0, 0.0,0.0), 10000.0);

  //Create the two point sounds
  PointSound sound1 = new PointSound();

  PointSound sound2 = new PointSound();

  /**
   * Build the view branch of the scene graph. In this case a key navigation
   * utility object is created and associated with the view transform so that
   * the view can be changed via the keyboard.
   * 
   * @return BranchGroup that is the root of the view branch
   */
  protected BranchGroup buildViewBranch(Canvas3D c) {
    BranchGroup viewBranch = new BranchGroup();
    Transform3D viewXfm = new Transform3D();
    viewXfm.set(new Vector3f(0.0f, 0.0f, 30.0f));
    TransformGroup viewXfmGroup = new TransformGroup(viewXfm);
    viewXfmGroup.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
    viewXfmGroup.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    ViewPlatform myViewPlatform = new ViewPlatform();
    BoundingSphere movingBounds = new BoundingSphere(new Point3d(0.0, 0.0,0.0), 100.0);
    BoundingLeaf boundLeaf = new BoundingLeaf(movingBounds);
    PhysicalBody myBody = new PhysicalBody();
    PhysicalEnvironment myEnvironment = new PhysicalEnvironment();
    viewXfmGroup.addChild(myViewPlatform);
    viewBranch.addChild(viewXfmGroup);
    View myView = new View();
    myView.addCanvas3D(c);
    myView.attachViewPlatform(myViewPlatform);
    myView.setPhysicalBody(myBody);
    myView.setPhysicalEnvironment(myEnvironment);
    KeyNavigatorBehavior keyNav = new KeyNavigatorBehavior(viewXfmGroup);
    keyNav.setSchedulingBounds(movingBounds);
    viewBranch.addChild(keyNav);
    //Create a sounds mixer to use our sounds with
    //and initialise it
    JavaSoundMixer myMixer = new JavaSoundMixer(myEnvironment);
    myMixer.initialize();
    return viewBranch;
  }

  /**
   * Add some lights to the scene graph
   * 
   * @param b
   *            BranchGroup that the lights are added to
   */
  protected void addLights(BranchGroup b) {
    Color3f ambLightColour = new Color3f(0.5f, 0.5f, 0.5f);
    AmbientLight ambLight = new AmbientLight(ambLightColour);
    ambLight.setInfluencingBounds(bounds);
    Color3f dirLightColour = new Color3f(1.0f, 1.0f, 1.0f);
    Vector3f dirLightDir = new Vector3f(-1.0f, -1.0f, -1.0f);
    DirectionalLight dirLight = new DirectionalLight(dirLightColour,dirLightDir);
    dirLight.setInfluencingBounds(bounds);
    b.addChild(ambLight);
    b.addChild(dirLight);
  }

  /**
   * This adds a continuous background sound to the branch group.
   * 
   * @param b
   *            BranchGroup to add the sound to.
   * @param soundFile
   *            String that is the name of the sound file.
   */
  protected void addBackgroundSound(BranchGroup b, String soundFile) {
    //Create a media container to load the file
    MediaContainer droneContainer = new MediaContainer(soundFile);
    //Create the background sound from the media container
    BackgroundSound drone = new BackgroundSound(droneContainer, 1.0f);
    //Activate the sound
    drone.setSchedulingBounds(bounds);
    drone.setEnable(true);
    //Set the sound to loop forever
    drone.setLoop(BackgroundSound.INFINITE_LOOPS);
    //Add it to the group
    b.addChild(drone);
  }

  /**
   * Add a sound to the transform group. This takes a point sound object and
   * loads into it a sounds from a given file. The edge of the sound's extent
   * is also defined in a parameter.
   * 
   * @param tg
   *            TransformGroup that the sound is to be added to
   * @param sound
   *            PointSound to be used
   * @param soundFile
   *            String that is the name of the sound file to be loaded
   * @param edge
   *            float that represents the sound's maximum extent
   */
  protected void addObjectSound(TransformGroup tg, PointSound sound,
      String soundFile, float edge) {
    //First we get the current transform so that we can
    //position the sound in the same place
    Transform3D objXfm = new Transform3D();
    Vector3f objPosition = new Vector3f();
    tg.getTransform(objXfm);
    objXfm.get(objPosition);
    //Create the media container to load the sound
    MediaContainer soundContainer = new MediaContainer(soundFile);
    //Use the loaded data in the sound
    sound.setSoundData(soundContainer);
    sound.setInitialGain(1.0f);
    //Set the position to that of the given transform
    sound.setPosition(new Point3f(objPosition));
    //Allow use to switch the sound on and off
    sound.setCapability(PointSound.ALLOW_ENABLE_READ);
    sound.setCapability(PointSound.ALLOW_ENABLE_WRITE);
    sound.setSchedulingBounds(bounds);
    //Set it off to start with
    sound.setEnable(false);
    //Set it to loop forever
    sound.setLoop(BackgroundSound.INFINITE_LOOPS);
    //Use the edge value to set to extent of the sound
    Point2f[] attenuation = { new Point2f(0.0f, 1.0f),
        new Point2f(edge, 0.1f) };
    sound.setDistanceGain(attenuation);
    //Add the sound to the transform group
    tg.addChild(sound);
  }

  protected BranchGroup buildContentBranch() {
    //Create the appearance
    Appearance app = new Appearance();
    Color3f ambientColour = new Color3f(1.0f, 0.0f, 0.0f);
    Color3f emissiveColour = new Color3f(0.0f, 0.0f, 0.0f);
    Color3f specularColour = new Color3f(1.0f, 1.0f, 1.0f);
    Color3f diffuseColour = new Color3f(1.0f, 0.0f, 0.0f);
    float shininess = 20.0f;
    app.setMaterial(new Material(ambientColour, emissiveColour,
        diffuseColour, specularColour, shininess));
    //Make the cube
    Box myCube = new Box(1.0f, 1.0f, 1.0f, app);

    TransformGroup cubeGroup = new TransformGroup();

    BranchGroup contentBranch = new BranchGroup();
    addLights(contentBranch);
    addObjectSound(cubeGroup, sound1, new String("file:./loop1.wav"), 10.0f);
    addObjectSound(cubeGroup, sound2, new String("file:./loop2.wav"), 20.0f);
    addBackgroundSound(contentBranch, new String("file:./loop3.wav"));

    cubeGroup.addChild(myCube);
    contentBranch.addChild(cubeGroup);
    return contentBranch;

  }

  public void actionPerformed(ActionEvent e) {
    if (e.getSource() == exitButton) {
      dispose();
      System.exit(0);
    } else if (e.getSource() == sound1Button) {
      if (sound1.getEnable())
        sound1.setEnable(false);
      else
        sound1.setEnable(true);
    } else if (e.getSource() == sound2Button) {
      sound2.setEnable(!sound2.getEnable());
    }
  }

  public SimpleSounds() {
    VirtualUniverse myUniverse = new VirtualUniverse();
    Locale myLocale = new Locale(myUniverse);
    //              buildUniverse(myCanvas3D);
    myLocale.addBranchGraph(buildContentBranch());
    myLocale.addBranchGraph(buildViewBranch(myCanvas3D));
    setTitle("SimpleSounds");
    setSize(400, 400);
    setLayout(new BorderLayout());
    Panel bottom = new Panel();
    bottom.add(sound1Button);
    bottom.add(sound2Button);
    bottom.add(exitButton);
    add(BorderLayout.CENTER, myCanvas3D);
    add(BorderLayout.SOUTH, bottom);
    exitButton.addActionListener(this);
    sound1Button.addActionListener(this);
    sound2Button.addActionListener(this);
    setVisible(true);
  }

  public static void main(String[] args) {
    SimpleSounds sw = new SimpleSounds();
  }
}

Thanks in advance for any help with this issue!

Brendan

[Greg Brannon]

I have no experience, but the Canvas3D API I found specifically prohibits a null parameter, making your statement at line 47 unacceptable. I accept that an API I found randomly on the web may not correspond to the actual library you're using, so please consider my suggestion suspect until proven otherwise.