There are two basic approaches to using the picking features of Java 3D: use objects of picking classes,or create custom picking classes and use instances of these custom classes.

The next list shows the simple recipe for using the mouse picking utility classes:

  1. Create your scene graph.
  2. Create a picking behavior object with root, canvas, and bounds specification.
  3. Add the behavior object to the scene graph.
  4. Enable the appropriate capabilities for scene graph objects.
 public BranchGroup createSceneGraph(Canvas3D canvas) {
    BranchGroup objRoot = new BranchGroup();

    TransformGroup objRotate = null;
    PickRotateBehavior pickRotate = null;
    Transform3D transform = new Transform3D();
    BoundingSphere behaveBounds = new BoundingSphere();

    // create ColorCube and PickRotateBehavior objects
    transform.setTranslation(new Vector3f(-0.6f, 0.0f, -0.6f));
    objRotate = new TransformGroup(transform);
    objRotate.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    objRotate.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
    objRotate.setCapability(TransformGroup.ENABLE_PICK_REPORTING);

    objRoot.addChild(objRotate);
    objRotate.addChild(new ColorCube(0.4));

    pickRotate = new PickRotateBehavior(objRoot, canvas, behaveBounds);
    objRoot.addChild(pickRotate);

    // add a second ColorCube object to the scene graph
    transform.setTranslation(new Vector3f(0.6f, 0.0f, -0.6f));
    objRotate = new TransformGroup(transform);
    objRotate.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
    objRotate.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
    objRotate.setCapability(TransformGroup.ENABLE_PICK_REPORTING);

    objRoot.addChild(objRotate);
    objRotate.addChild(new ColorCube(0.4));

    objRoot.compile();

    return objRoot;
}