ExAmbientLight.java Source code

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Here is the source code for ExAmbientLight.java

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//
//CLASS
//ExAmbientLight - illustrate use of ambient lights
//
//LESSON
//Add an AmbientLight node to illuminate a scene.
//
//SEE ALSO
//ExDirectionalLight
//ExPointLight
//ExSpotLight
//
//AUTHOR
//David R. Nadeau / San Diego Supercomputer Center
//

import java.applet.Applet;
import java.awt.AWTEvent;
import java.awt.BorderLayout;
import java.awt.CheckboxMenuItem;
import java.awt.Component;
import java.awt.Cursor;
import java.awt.Frame;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.InputEvent;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.MouseEvent;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.io.File;
import java.util.Enumeration;
import java.util.EventListener;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.Appearance;
import javax.media.j3d.Behavior;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.DirectionalLight;
import javax.media.j3d.Group;
import javax.media.j3d.Light;
import javax.media.j3d.Material;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.media.j3d.WakeupCriterion;
import javax.media.j3d.WakeupOnAWTEvent;
import javax.media.j3d.WakeupOnElapsedFrames;
import javax.media.j3d.WakeupOr;
import javax.vecmath.Color3f;
import javax.vecmath.Matrix4d;
import javax.vecmath.Point3d;
import javax.vecmath.Point3f;
import javax.vecmath.Vector3d;
import javax.vecmath.Vector3f;

import com.sun.j3d.utils.geometry.Primitive;
import com.sun.j3d.utils.geometry.Sphere;
import com.sun.j3d.utils.universe.PlatformGeometry;
import com.sun.j3d.utils.universe.SimpleUniverse;
import com.sun.j3d.utils.universe.Viewer;
import com.sun.j3d.utils.universe.ViewingPlatform;

public class ExAmbientLight extends Java3DFrame {
    //--------------------------------------------------------------
    //  SCENE CONTENT
    //--------------------------------------------------------------

    //
    //  Nodes (updated via menu)
    //
    private AmbientLight light = null;

    //
    //  Build scene
    //
    public Group buildScene() {
        // Get the current color
        Color3f color = (Color3f) colors[currentColor].value;

        // Turn off the example headlight
        setHeadlightEnable(false);

        // Build the scene group
        Group scene = new Group();

        // BEGIN EXAMPLE TOPIC
        // Create influencing bounds
        BoundingSphere worldBounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), // Center
                1000.0); // Extent

        // Set the light color and its influencing bounds
        light = new AmbientLight();
        light.setEnable(lightOnOff);
        light.setColor(color);
        light.setCapability(AmbientLight.ALLOW_STATE_WRITE);
        light.setCapability(AmbientLight.ALLOW_COLOR_WRITE);
        light.setInfluencingBounds(worldBounds);
        scene.addChild(light);
        // END EXAMPLE TOPIC

        // Build foreground geometry
        scene.addChild(new SphereGroup());

        return scene;
    }

    //--------------------------------------------------------------
    //  USER INTERFACE
    //--------------------------------------------------------------

    //
    //  Main
    //
    public static void main(String[] args) {
        ExAmbientLight ex = new ExAmbientLight();
        ex.initialize(args);
        ex.buildUniverse();
        ex.showFrame();
    }

    //  On/off choices
    private boolean lightOnOff = true;

    private CheckboxMenuItem lightOnOffMenu;

    //  Color menu choices
    private NameValue[] colors = { new NameValue("White", White), new NameValue("Gray", Gray),
            new NameValue("Black", Black), new NameValue("Red", Red), new NameValue("Yellow", Yellow),
            new NameValue("Green", Green), new NameValue("Cyan", Cyan), new NameValue("Blue", Blue),
            new NameValue("Magenta", Magenta), };

    private int currentColor = 0;

    private CheckboxMenu colorMenu = null;

    //
    //  Initialize the GUI (application and applet)
    //
    public void initialize(String[] args) {
        // Initialize the window, menubar, etc.
        super.initialize(args);
        exampleFrame.setTitle("Java 3D Ambient Light Example");

        //
        //  Add a menubar menu to change node parameters
        //    Light on/off
        //    Color -->
        //

        Menu m = new Menu("AmbientLight");

        lightOnOffMenu = new CheckboxMenuItem("Light on/off", lightOnOff);
        lightOnOffMenu.addItemListener(this);
        m.add(lightOnOffMenu);

        colorMenu = new CheckboxMenu("Color", colors, currentColor, this);
        m.add(colorMenu);

        exampleMenuBar.add(m);
    }

    //
    //  Handle checkboxes and menu choices
    //
    public void checkboxChanged(CheckboxMenu menu, int check) {
        if (menu == colorMenu) {
            // Change the light color
            currentColor = check;
            Color3f color = (Color3f) colors[check].value;
            light.setColor(color);
            return;
        }

        // Handle all other checkboxes
        super.checkboxChanged(menu, check);
    }

    public void itemStateChanged(ItemEvent event) {
        Object src = event.getSource();
        if (src == lightOnOffMenu) {
            // Turn the light on or off
            lightOnOff = lightOnOffMenu.getState();
            light.setEnable(lightOnOff);
            return;
        }

        // Handle all other checkboxes
        super.itemStateChanged(event);
    }
}

//
//CLASS
//SphereGroup - create a group of spheres on the XY plane
//
//DESCRIPTION
//An XY grid of spheres is created. The number of spheres in X and Y,
//the spacing in X and Y, the sphere radius, and the appearance can
//all be set.
//
//This grid of spheres is used by several of the examples as a generic
//bit of foreground geometry.
//
//SEE ALSO
//Ex*Light
//ExBackground*
//
//AUTHOR
//David R. Nadeau / San Diego Supercomputer Center
//

class SphereGroup extends Group {
    //  Constructors
    public SphereGroup() {
        //    radius x,y spacing x,y count appearance
        this(0.25f, 0.75f, 0.75f, 5, 5, null);
    }

    public SphereGroup(Appearance app) {
        //    radius x,y spacing x,y count appearance
        this(0.25f, 0.75f, 0.75f, 5, 5, app);
    }

    public SphereGroup(float radius, float xSpacing, float ySpacing, int xCount, int yCount) {
        this(radius, xSpacing, ySpacing, xCount, yCount, null);
    }

    public SphereGroup(float radius, float xSpacing, float ySpacing, int xCount, int yCount, Appearance app) {
        if (app == null) {
            app = new Appearance();
            Material material = new Material();
            material.setDiffuseColor(new Color3f(0.8f, 0.8f, 0.8f));
            material.setSpecularColor(new Color3f(0.0f, 0.0f, 0.0f));
            material.setShininess(0.0f);
            app.setMaterial(material);
        }

        double xStart = -xSpacing * (double) (xCount - 1) / 2.0;
        double yStart = -ySpacing * (double) (yCount - 1) / 2.0;

        Sphere sphere = null;
        TransformGroup trans = null;
        Transform3D t3d = new Transform3D();
        Vector3d vec = new Vector3d();
        double x, y = yStart, z = 0.0;
        for (int i = 0; i < yCount; i++) {
            x = xStart;
            for (int j = 0; j < xCount; j++) {
                vec.set(x, y, z);
                t3d.setTranslation(vec);
                trans = new TransformGroup(t3d);
                addChild(trans);

                sphere = new Sphere(radius, // sphere radius
                        Primitive.GENERATE_NORMALS, // generate normals
                        16, // 16 divisions radially
                        app); // it's appearance
                trans.addChild(sphere);
                x += xSpacing;
            }
            y += ySpacing;
        }
    }
}

/**
 * The Example class is a base class extended by example applications. The class
 * provides basic features to create a top-level frame, add a menubar and
 * Canvas3D, build the universe, set up "examine" and "walk" style navigation
 * behaviors, and provide hooks so that subclasses can add 3D content to the
 * example's universe.
 * <P>
 * Using this Example class simplifies the construction of example applications,
 * enabling the author to focus upon 3D content and not the busywork of creating
 * windows, menus, and universes.
 * 
 * @version 1.0, 98/04/16
 * @author David R. Nadeau, San Diego Supercomputer Center
 */

class Java3DFrame extends Applet implements WindowListener, ActionListener, ItemListener, CheckboxMenuListener {
    //  Navigation types
    public final static int Walk = 0;

    public final static int Examine = 1;

    //  Should the scene be compiled?
    private boolean shouldCompile = true;

    //  GUI objects for our subclasses
    protected Java3DFrame example = null;

    protected Frame exampleFrame = null;

    protected MenuBar exampleMenuBar = null;

    protected Canvas3D exampleCanvas = null;

    protected TransformGroup exampleViewTransform = null;

    protected TransformGroup exampleSceneTransform = null;

    protected boolean debug = false;

    //  Private GUI objects and state
    private boolean headlightOnOff = true;

    private int navigationType = Examine;

    private CheckboxMenuItem headlightMenuItem = null;

    private CheckboxMenuItem walkMenuItem = null;

    private CheckboxMenuItem examineMenuItem = null;

    private DirectionalLight headlight = null;

    private ExamineViewerBehavior examineBehavior = null;

    private WalkViewerBehavior walkBehavior = null;

    //--------------------------------------------------------------
    //  ADMINISTRATION
    //--------------------------------------------------------------

    /**
     * The main program entry point when invoked as an application. Each example
     * application that extends this class must define their own main.
     * 
     * @param args
     *            a String array of command-line arguments
     */
    public static void main(String[] args) {
        Java3DFrame ex = new Java3DFrame();
        ex.initialize(args);
        ex.buildUniverse();
        ex.showFrame();
    }

    /**
     * Constructs a new Example object.
     * 
     * @return a new Example that draws no 3D content
     */
    public Java3DFrame() {
        // Do nothing
    }

    /**
     * Initializes the application when invoked as an applet.
     */
    public void init() {
        // Collect properties into String array
        String[] args = new String[2];
        // NOTE: to be done still...

        this.initialize(args);
        this.buildUniverse();
        this.showFrame();

        // NOTE: add something to the browser page?
    }

    /**
     * Initializes the Example by parsing command-line arguments, building an
     * AWT Frame, constructing a menubar, and creating the 3D canvas.
     * 
     * @param args
     *            a String array of command-line arguments
     */
    protected void initialize(String[] args) {
        example = this;

        // Parse incoming arguments
        parseArgs(args);

        // Build the frame
        if (debug)
            System.err.println("Building GUI...");
        exampleFrame = new Frame();
        exampleFrame.setSize(640, 480);
        exampleFrame.setTitle("Java 3D Example");
        exampleFrame.setLayout(new BorderLayout());

        // Set up a close behavior
        exampleFrame.addWindowListener(this);

        // Create a canvas
        exampleCanvas = new Canvas3D(null);
        exampleCanvas.setSize(630, 460);
        exampleFrame.add("Center", exampleCanvas);

        // Build the menubar
        exampleMenuBar = this.buildMenuBar();
        exampleFrame.setMenuBar(exampleMenuBar);

        // Pack
        exampleFrame.pack();
        exampleFrame.validate();
        //      exampleFrame.setVisible( true );
    }

    /**
     * Parses incoming command-line arguments. Applications that subclass this
     * class may override this method to support their own command-line
     * arguments.
     * 
     * @param args
     *            a String array of command-line arguments
     */
    protected void parseArgs(String[] args) {
        for (int i = 0; i < args.length; i++) {
            if (args[i].equals("-d"))
                debug = true;
        }
    }

    //--------------------------------------------------------------
    //  SCENE CONTENT
    //--------------------------------------------------------------

    /**
     * Builds the 3D universe by constructing a virtual universe (via
     * SimpleUniverse), a view platform (via SimpleUniverse), and a view (via
     * SimpleUniverse). A headlight is added and a set of behaviors initialized
     * to handle navigation types.
     */
    protected void buildUniverse() {
        //
        //  Create a SimpleUniverse object, which builds:
        //
        //    - a Locale using the given hi-res coordinate origin
        //
        //    - a ViewingPlatform which in turn builds:
        //          - a MultiTransformGroup with which to move the
        //            the ViewPlatform about
        //
        //          - a ViewPlatform to hold the view
        //
        //          - a BranchGroup to hold avatar geometry (if any)
        //
        //          - a BranchGroup to hold view platform
        //            geometry (if any)
        //
        //    - a Viewer which in turn builds:
        //          - a PhysicalBody which characterizes the user's
        //            viewing preferences and abilities
        //
        //          - a PhysicalEnvironment which characterizes the
        //            user's rendering hardware and software
        //
        //          - a JavaSoundMixer which initializes sound
        //            support within the 3D environment
        //
        //          - a View which renders the scene into a Canvas3D
        //
        //  All of these actions could be done explicitly, but
        //  using the SimpleUniverse utilities simplifies the code.
        //
        if (debug)
            System.err.println("Building scene graph...");
        SimpleUniverse universe = new SimpleUniverse(null, // Hi-res coordinate
                // for the origin -
                // use default
                1, // Number of transforms in MultiTransformGroup
                exampleCanvas, // Canvas3D into which to draw
                null); // URL for user configuration file - use defaults

        //
        //  Get the viewer and create an audio device so that
        //  sound will be enabled in this content.
        //
        Viewer viewer = universe.getViewer();
        viewer.createAudioDevice();

        //
        //  Get the viewing platform created by SimpleUniverse.
        //  From that platform, get the inner-most TransformGroup
        //  in the MultiTransformGroup. That inner-most group
        //  contains the ViewPlatform. It is this inner-most
        //  TransformGroup we need in order to:
        //
        //    - add a "headlight" that always aims forward from
        //       the viewer
        //
        //    - change the viewing direction in a "walk" style
        //
        //  The inner-most TransformGroup's transform will be
        //  changed by the walk behavior (when enabled).
        //
        ViewingPlatform viewingPlatform = universe.getViewingPlatform();
        exampleViewTransform = viewingPlatform.getViewPlatformTransform();

        //
        //  Create a "headlight" as a forward-facing directional light.
        //  Set the light's bounds to huge. Since we want the light
        //  on the viewer's "head", we need the light within the
        //  TransformGroup containing the ViewPlatform. The
        //  ViewingPlatform class creates a handy hook to do this
        //  called "platform geometry". The PlatformGeometry class is
        //  subclassed off of BranchGroup, and is intended to contain
        //  a description of the 3D platform itself... PLUS a headlight!
        //  So, to add the headlight, create a new PlatformGeometry group,
        //  add the light to it, then add that platform geometry to the
        //  ViewingPlatform.
        //
        BoundingSphere allBounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100000.0);

        PlatformGeometry pg = new PlatformGeometry();
        headlight = new DirectionalLight();
        headlight.setColor(White);
        headlight.setDirection(new Vector3f(0.0f, 0.0f, -1.0f));
        headlight.setInfluencingBounds(allBounds);
        headlight.setCapability(Light.ALLOW_STATE_WRITE);
        pg.addChild(headlight);
        viewingPlatform.setPlatformGeometry(pg);

        //
        //  Create the 3D content BranchGroup, containing:
        //
        //    - a TransformGroup who's transform the examine behavior
        //      will change (when enabled).
        //
        //    - 3D geometry to view
        //
        // Build the scene root
        BranchGroup sceneRoot = new BranchGroup();

        // Build a transform that we can modify
        exampleSceneTransform = new TransformGroup();
        exampleSceneTransform.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
        exampleSceneTransform.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        exampleSceneTransform.setCapability(Group.ALLOW_CHILDREN_EXTEND);

        //
        //  Build the scene, add it to the transform, and add
        //  the transform to the scene root
        //
        if (debug)
            System.err.println("  scene...");
        Group scene = this.buildScene();
        exampleSceneTransform.addChild(scene);
        sceneRoot.addChild(exampleSceneTransform);

        //
        //  Create a pair of behaviors to implement two navigation
        //  types:
        //
        //    - "examine": a style where mouse drags rotate about
        //      the scene's origin as if it is an object under
        //      examination. This is similar to the "Examine"
        //      navigation type used by VRML browsers.
        //
        //    - "walk": a style where mouse drags rotate about
        //      the viewer's center as if the viewer is turning
        //      about to look at a scene they are in. This is
        //      similar to the "Walk" navigation type used by
        //      VRML browsers.
        //
        //  Aim the examine behavior at the scene's TransformGroup
        //  and add the behavior to the scene root.
        //
        //  Aim the walk behavior at the viewing platform's
        //  TransformGroup and add the behavior to the scene root.
        //
        //  Enable one (and only one!) of the two behaviors
        //  depending upon the current navigation type.
        //
        examineBehavior = new ExamineViewerBehavior(exampleSceneTransform, // Transform
                // gorup
                // to
                // modify
                exampleFrame); // Parent frame for cusor changes
        examineBehavior.setSchedulingBounds(allBounds);
        sceneRoot.addChild(examineBehavior);

        walkBehavior = new WalkViewerBehavior(exampleViewTransform, // Transform
                // group to
                // modify
                exampleFrame); // Parent frame for cusor changes
        walkBehavior.setSchedulingBounds(allBounds);
        sceneRoot.addChild(walkBehavior);

        if (navigationType == Walk) {
            examineBehavior.setEnable(false);
            walkBehavior.setEnable(true);
        } else {
            examineBehavior.setEnable(true);
            walkBehavior.setEnable(false);
        }

        //
        //  Compile the scene branch group and add it to the
        //  SimpleUniverse.
        //
        if (shouldCompile)
            sceneRoot.compile();
        universe.addBranchGraph(sceneRoot);

        reset();
    }

    /**
     * Builds the scene. Example application subclasses should replace this
     * method with their own method to build 3D content.
     * 
     * @return a Group containing 3D content to display
     */
    public Group buildScene() {
        // Build the scene group containing nothing
        Group scene = new Group();
        return scene;
    }

    //--------------------------------------------------------------
    //  SET/GET METHODS
    //--------------------------------------------------------------

    /**
     * Sets the headlight on/off state. The headlight faces forward in the
     * direction the viewer is facing. Example applications that add their own
     * lights will typically turn the headlight off. A standard menu item
     * enables the headlight to be turned on and off via user control.
     * 
     * @param onOff
     *            a boolean turning the light on (true) or off (false)
     */
    public void setHeadlightEnable(boolean onOff) {
        headlightOnOff = onOff;
        if (headlight != null)
            headlight.setEnable(headlightOnOff);
        if (headlightMenuItem != null)
            headlightMenuItem.setState(headlightOnOff);
    }

    /**
     * Gets the headlight on/off state.
     * 
     * @return a boolean indicating if the headlight is on or off
     */
    public boolean getHeadlightEnable() {
        return headlightOnOff;
    }

    /**
     * Sets the navigation type to be either Examine or Walk. The Examine
     * navigation type sets up behaviors that use mouse drags to rotate and
     * translate scene content as if it is an object held at arm's length and
     * under examination. The Walk navigation type uses mouse drags to rotate
     * and translate the viewer as if they are walking through the content. The
     * Examine type is the default.
     * 
     * @param nav
     *            either Walk or Examine
     */
    public void setNavigationType(int nav) {
        if (nav == Walk) {
            navigationType = Walk;
            if (walkMenuItem != null)
                walkMenuItem.setState(true);
            if (examineMenuItem != null)
                examineMenuItem.setState(false);
            if (walkBehavior != null)
                walkBehavior.setEnable(true);
            if (examineBehavior != null)
                examineBehavior.setEnable(false);
        } else {
            navigationType = Examine;
            if (walkMenuItem != null)
                walkMenuItem.setState(false);
            if (examineMenuItem != null)
                examineMenuItem.setState(true);
            if (walkBehavior != null)
                walkBehavior.setEnable(false);
            if (examineBehavior != null)
                examineBehavior.setEnable(true);
        }
    }

    /**
     * Gets the current navigation type, returning either Walk or Examine.
     * 
     * @return either Walk or Examine
     */
    public int getNavigationType() {
        return navigationType;
    }

    /**
     * Sets whether the scene graph should be compiled or not. Normally this is
     * always a good idea. For some example applications that use this Example
     * framework, it is useful to disable compilation - particularly when nodes
     * and node components will need to be made un-live in order to make
     * changes. Once compiled, such components can be made un-live, but they are
     * still unchangable unless appropriate capabilities have been set.
     * 
     * @param onOff
     *            a boolean turning compilation on (true) or off (false)
     */
    public void setCompilable(boolean onOff) {
        shouldCompile = onOff;
    }

    /**
     * Gets whether the scene graph will be compiled or not.
     * 
     * @return a boolean indicating if scene graph compilation is on or off
     */
    public boolean getCompilable() {
        return shouldCompile;
    }

    //These methods will be replaced
    //  Set the view position and direction
    public void setViewpoint(Point3f position, Vector3f direction) {
        Transform3D t = new Transform3D();
        t.set(new Vector3f(position));
        exampleViewTransform.setTransform(t);
        // how to set direction?
    }

    //  Reset transforms
    public void reset() {
        Transform3D trans = new Transform3D();
        exampleSceneTransform.setTransform(trans);
        trans.set(new Vector3f(0.0f, 0.0f, 10.0f));
        exampleViewTransform.setTransform(trans);
        setNavigationType(navigationType);
    }

    //
    //  Gets the URL (with file: prepended) for the current directory.
    //  This is a terrible hack needed in the Alpha release of Java3D
    //  in order to build a full path URL for loading sounds with
    //  MediaContainer. When MediaContainer is fully implemented,
    //  it should handle relative path names, but not yet.
    //
    public String getCurrentDirectory() {
        // Create a bogus file so that we can query it's path
        File dummy = new File("dummy.tmp");
        String dummyPath = dummy.getAbsolutePath();

        // strip "/dummy.tmp" from end of dummyPath and put into 'path'
        if (dummyPath.endsWith(File.separator + "dummy.tmp")) {
            int index = dummyPath.lastIndexOf(File.separator + "dummy.tmp");
            if (index >= 0) {
                int pathLength = index + 5; // pre-pend 'file:'
                char[] charPath = new char[pathLength];
                dummyPath.getChars(0, index, charPath, 5);
                String path = new String(charPath, 0, pathLength);
                path = "file:" + path.substring(5, pathLength);
                return path + File.separator;
            }
        }
        return dummyPath + File.separator;
    }

    //--------------------------------------------------------------
    //  USER INTERFACE
    //--------------------------------------------------------------

    /**
     * Builds the example AWT Frame menubar. Standard menus and their options
     * are added. Applications that subclass this class should build their
     * menubar additions within their initialize method.
     * 
     * @return a MenuBar for the AWT Frame
     */
    private MenuBar buildMenuBar() {
        // Build the menubar
        MenuBar menuBar = new MenuBar();

        // File menu
        Menu m = new Menu("File");
        m.addActionListener(this);

        m.add("Exit");

        menuBar.add(m);

        // View menu
        m = new Menu("View");
        m.addActionListener(this);

        m.add("Reset view");

        m.addSeparator();

        walkMenuItem = new CheckboxMenuItem("Walk");
        walkMenuItem.addItemListener(this);
        m.add(walkMenuItem);

        examineMenuItem = new CheckboxMenuItem("Examine");
        examineMenuItem.addItemListener(this);
        m.add(examineMenuItem);

        if (navigationType == Walk) {
            walkMenuItem.setState(true);
            examineMenuItem.setState(false);
        } else {
            walkMenuItem.setState(false);
            examineMenuItem.setState(true);
        }

        m.addSeparator();

        headlightMenuItem = new CheckboxMenuItem("Headlight on/off");
        headlightMenuItem.addItemListener(this);
        headlightMenuItem.setState(headlightOnOff);
        m.add(headlightMenuItem);

        menuBar.add(m);

        return menuBar;
    }

    /**
     * Shows the application's frame, making it and its menubar, 3D canvas, and
     * 3D content visible.
     */
    public void showFrame() {
        exampleFrame.show();
    }

    /**
     * Quits the application.
     */
    public void quit() {
        System.exit(0);
    }

    /**
     * Handles menu selections.
     * 
     * @param event
     *            an ActionEvent indicating what menu action requires handling
     */
    public void actionPerformed(ActionEvent event) {
        String arg = event.getActionCommand();
        if (arg.equals("Reset view"))
            reset();
        else if (arg.equals("Exit"))
            quit();
    }

    /**
     * Handles checkbox items on a CheckboxMenu. The Example class has none of
     * its own, but subclasses may have some.
     * 
     * @param menu
     *            which CheckboxMenu needs action
     * @param check
     *            which CheckboxMenu item has changed
     */
    public void checkboxChanged(CheckboxMenu menu, int check) {
        // None for us
    }

    /**
     * Handles on/off checkbox items on a standard menu.
     * 
     * @param event
     *            an ItemEvent indicating what requires handling
     */
    public void itemStateChanged(ItemEvent event) {
        Object src = event.getSource();
        boolean state;
        if (src == headlightMenuItem) {
            state = headlightMenuItem.getState();
            headlight.setEnable(state);
        } else if (src == walkMenuItem)
            setNavigationType(Walk);
        else if (src == examineMenuItem)
            setNavigationType(Examine);
    }

    /**
     * Handles a window closing event notifying the application that the user
     * has chosen to close the application without selecting the "Exit" menu
     * item.
     * 
     * @param event
     *            a WindowEvent indicating the window is closing
     */
    public void windowClosing(WindowEvent event) {
        quit();
    }

    public void windowClosed(WindowEvent event) {
    }

    public void windowOpened(WindowEvent event) {
    }

    public void windowIconified(WindowEvent event) {
    }

    public void windowDeiconified(WindowEvent event) {
    }

    public void windowActivated(WindowEvent event) {
    }

    public void windowDeactivated(WindowEvent event) {
    }

    //  Well known colors, positions, and directions
    public final static Color3f White = new Color3f(1.0f, 1.0f, 1.0f);

    public final static Color3f Gray = new Color3f(0.7f, 0.7f, 0.7f);

    public final static Color3f DarkGray = new Color3f(0.2f, 0.2f, 0.2f);

    public final static Color3f Black = new Color3f(0.0f, 0.0f, 0.0f);

    public final static Color3f Red = new Color3f(1.0f, 0.0f, 0.0f);

    public final static Color3f DarkRed = new Color3f(0.3f, 0.0f, 0.0f);

    public final static Color3f Yellow = new Color3f(1.0f, 1.0f, 0.0f);

    public final static Color3f DarkYellow = new Color3f(0.3f, 0.3f, 0.0f);

    public final static Color3f Green = new Color3f(0.0f, 1.0f, 0.0f);

    public final static Color3f DarkGreen = new Color3f(0.0f, 0.3f, 0.0f);

    public final static Color3f Cyan = new Color3f(0.0f, 1.0f, 1.0f);

    public final static Color3f Blue = new Color3f(0.0f, 0.0f, 1.0f);

    public final static Color3f DarkBlue = new Color3f(0.0f, 0.0f, 0.3f);

    public final static Color3f Magenta = new Color3f(1.0f, 0.0f, 1.0f);

    public final static Vector3f PosX = new Vector3f(1.0f, 0.0f, 0.0f);

    public final static Vector3f NegX = new Vector3f(-1.0f, 0.0f, 0.0f);

    public final static Vector3f PosY = new Vector3f(0.0f, 1.0f, 0.0f);

    public final static Vector3f NegY = new Vector3f(0.0f, -1.0f, 0.0f);

    public final static Vector3f PosZ = new Vector3f(0.0f, 0.0f, 1.0f);

    public final static Vector3f NegZ = new Vector3f(0.0f, 0.0f, -1.0f);

    public final static Point3f Origin = new Point3f(0.0f, 0.0f, 0.0f);

    public final static Point3f PlusX = new Point3f(0.75f, 0.0f, 0.0f);

    public final static Point3f MinusX = new Point3f(-0.75f, 0.0f, 0.0f);

    public final static Point3f PlusY = new Point3f(0.0f, 0.75f, 0.0f);

    public final static Point3f MinusY = new Point3f(0.0f, -0.75f, 0.0f);

    public final static Point3f PlusZ = new Point3f(0.0f, 0.0f, 0.75f);

    public final static Point3f MinusZ = new Point3f(0.0f, 0.0f, -0.75f);
}

//
//INTERFACE
//CheckboxMenuListener - listen for checkbox change events
//
//DESCRIPTION
//The checkboxChanged method is called by users of this class
//to notify the listener when a checkbox choice has changed on
//a CheckboxMenu class menu.
//

interface CheckboxMenuListener extends EventListener {
    public void checkboxChanged(CheckboxMenu menu, int check);
}

/**
 * ExamineViewerBehavior
 * 
 * @version 1.0, 98/04/16
 */

/**
 * Wakeup on mouse button presses, releases, and mouse movements and generate
 * transforms in an "examination style" that enables the user to rotate,
 * translation, and zoom an object as if it is held at arm's length. Such an
 * examination style is similar to the "Examine" navigation type used by VRML
 * browsers.
 * 
 * The behavior maps mouse drags to different transforms depending upon the
 * mosue button held down:
 * 
 * Button 1 (left) Horizontal movement --> Y-axis rotation Vertical movement -->
 * X-axis rotation
 * 
 * Button 2 (middle) Horizontal movement --> nothing Vertical movement -->
 * Z-axis translation
 * 
 * Button 3 (right) Horizontal movement --> X-axis translation Vertical movement
 * --> Y-axis translation
 * 
 * To support systems with 2 or 1 mouse buttons, the following alternate
 * mappings are supported while dragging with any mouse button held down and
 * zero or more keyboard modifiers held down:
 * 
 * No modifiers = Button 1 ALT = Button 2 Meta = Button 3 Control = Button 3
 * 
 * The behavior automatically modifies a TransformGroup provided to the
 * constructor. The TransformGroup's transform can be set at any time by the
 * application or other behaviors to cause the examine rotation and translation
 * to be reset.
 */

// This class is inspired by the MouseBehavior, MouseRotate,
// MouseTranslate, and MouseZoom utility behaviors provided with
// Java 3D. This class differs from those utilities in that it:
//
//    (a) encapsulates all three behaviors into one in order to
//        enforce a specific "Examine" symantic
//
//    (b) supports set/get of the rotation and translation factors
//        that control the speed of movement.
//
//    (c) supports the "Control" modifier as an alternative to the
//        "Meta" modifier not present on PC, Mac, and most non-Sun
//        keyboards. This makes button3 behavior usable on PCs,
//        Macs, and other systems with fewer than 3 mouse buttons.

class ExamineViewerBehavior extends ViewerBehavior {
    // Previous cursor location
    protected int previousX = 0;

    protected int previousY = 0;

    // Saved standard cursor
    protected Cursor savedCursor = null;

    /**
     * Construct an examine behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into a
     * transform group given later with the setTransformGroup( ) method.
     */
    public ExamineViewerBehavior() {
        super();
    }

    /**
     * Construct an examine behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into a
     * transform group given later with the setTransformGroup( ) method.
     * 
     * @param parent
     *            The AWT Component that contains the area generating mouse
     *            events.
     */
    public ExamineViewerBehavior(Component parent) {
        super(parent);
    }

    /**
     * Construct an examine behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into the
     * given transform group.
     * 
     * @param transformGroup
     *            The transform group to be modified by the behavior.
     */
    public ExamineViewerBehavior(TransformGroup transformGroup) {
        super();
        subjectTransformGroup = transformGroup;
    }

    /**
     * Construct an examine behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into the
     * given transform group.
     * 
     * @param transformGroup
     *            The transform group to be modified by the behavior.
     * @param parent
     *            The AWT Component that contains the area generating mouse
     *            events.
     */
    public ExamineViewerBehavior(TransformGroup transformGroup, Component parent) {
        super(parent);
        subjectTransformGroup = transformGroup;
    }

    /**
     * Respond to a button1 event (press, release, or drag).
     * 
     * @param mouseEvent
     *            A MouseEvent to respond to.
     */
    public void onButton1(MouseEvent mev) {
        if (subjectTransformGroup == null)
            return;

        int x = mev.getX();
        int y = mev.getY();

        if (mev.getID() == MouseEvent.MOUSE_PRESSED) {
            // Mouse button pressed: record position
            previousX = x;
            previousY = y;

            // Change to a "move" cursor
            if (parentComponent != null) {
                savedCursor = parentComponent.getCursor();
                parentComponent.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
            }
            return;
        }
        if (mev.getID() == MouseEvent.MOUSE_RELEASED) {
            // Mouse button released: do nothing

            // Switch the cursor back
            if (parentComponent != null)
                parentComponent.setCursor(savedCursor);
            return;
        }

        //
        // Mouse moved while button down: create a rotation
        //
        // Compute the delta in X and Y from the previous
        // position. Use the delta to compute rotation
        // angles with the mapping:
        //
        //   positive X mouse delta --> positive Y-axis rotation
        //   positive Y mouse delta --> positive X-axis rotation
        //
        // where positive X mouse movement is to the right, and
        // positive Y mouse movement is **down** the screen.
        //
        int deltaX = x - previousX;
        int deltaY = y - previousY;

        if (deltaX > UNUSUAL_XDELTA || deltaX < -UNUSUAL_XDELTA || deltaY > UNUSUAL_YDELTA
                || deltaY < -UNUSUAL_YDELTA) {
            // Deltas are too huge to be believable. Probably a glitch.
            // Don't record the new XY location, or do anything.
            return;
        }

        double xRotationAngle = deltaY * XRotationFactor;
        double yRotationAngle = deltaX * YRotationFactor;

        //
        // Build transforms
        //
        transform1.rotX(xRotationAngle);
        transform2.rotY(yRotationAngle);

        // Get and save the current transform matrix
        subjectTransformGroup.getTransform(currentTransform);
        currentTransform.get(matrix);
        translate.set(matrix.m03, matrix.m13, matrix.m23);

        // Translate to the origin, rotate, then translate back
        currentTransform.setTranslation(origin);
        currentTransform.mul(transform1, currentTransform);
        currentTransform.mul(transform2, currentTransform);
        currentTransform.setTranslation(translate);

        // Update the transform group
        subjectTransformGroup.setTransform(currentTransform);

        previousX = x;
        previousY = y;
    }

    /**
     * Respond to a button2 event (press, release, or drag).
     * 
     * @param mouseEvent
     *            A MouseEvent to respond to.
     */
    public void onButton2(MouseEvent mev) {
        if (subjectTransformGroup == null)
            return;

        int x = mev.getX();
        int y = mev.getY();

        if (mev.getID() == MouseEvent.MOUSE_PRESSED) {
            // Mouse button pressed: record position
            previousX = x;
            previousY = y;

            // Change to a "move" cursor
            if (parentComponent != null) {
                savedCursor = parentComponent.getCursor();
                parentComponent.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
            }
            return;
        }
        if (mev.getID() == MouseEvent.MOUSE_RELEASED) {
            // Mouse button released: do nothing

            // Switch the cursor back
            if (parentComponent != null)
                parentComponent.setCursor(savedCursor);
            return;
        }

        //
        // Mouse moved while button down: create a translation
        //
        // Compute the delta in Y from the previous
        // position. Use the delta to compute translation
        // distances with the mapping:
        //
        //   positive Y mouse delta --> positive Y-axis translation
        //
        // where positive X mouse movement is to the right, and
        // positive Y mouse movement is **down** the screen.
        //
        int deltaY = y - previousY;

        if (deltaY > UNUSUAL_YDELTA || deltaY < -UNUSUAL_YDELTA) {
            // Deltas are too huge to be believable. Probably a glitch.
            // Don't record the new XY location, or do anything.
            return;
        }

        double zTranslationDistance = deltaY * ZTranslationFactor;

        //
        // Build transforms
        //
        translate.set(0.0, 0.0, zTranslationDistance);
        transform1.set(translate);

        // Get and save the current transform
        subjectTransformGroup.getTransform(currentTransform);

        // Translate as needed
        currentTransform.mul(transform1, currentTransform);

        // Update the transform group
        subjectTransformGroup.setTransform(currentTransform);

        previousX = x;
        previousY = y;
    }

    /**
     * Respond to a button3 event (press, release, or drag).
     * 
     * @param mouseEvent
     *            A MouseEvent to respond to.
     */
    public void onButton3(MouseEvent mev) {
        if (subjectTransformGroup == null)
            return;

        int x = mev.getX();
        int y = mev.getY();

        if (mev.getID() == MouseEvent.MOUSE_PRESSED) {
            // Mouse button pressed: record position
            previousX = x;
            previousY = y;

            // Change to a "move" cursor
            if (parentComponent != null) {
                savedCursor = parentComponent.getCursor();
                parentComponent.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
            }
            return;
        }
        if (mev.getID() == MouseEvent.MOUSE_RELEASED) {
            // Mouse button released: do nothing

            // Switch the cursor back
            if (parentComponent != null)
                parentComponent.setCursor(savedCursor);
            return;
        }

        //
        // Mouse moved while button down: create a translation
        //
        // Compute the delta in X and Y from the previous
        // position. Use the delta to compute translation
        // distances with the mapping:
        //
        //   positive X mouse delta --> positive X-axis translation
        //   positive Y mouse delta --> negative Y-axis translation
        //
        // where positive X mouse movement is to the right, and
        // positive Y mouse movement is **down** the screen.
        //
        int deltaX = x - previousX;
        int deltaY = y - previousY;

        if (deltaX > UNUSUAL_XDELTA || deltaX < -UNUSUAL_XDELTA || deltaY > UNUSUAL_YDELTA
                || deltaY < -UNUSUAL_YDELTA) {
            // Deltas are too huge to be believable. Probably a glitch.
            // Don't record the new XY location, or do anything.
            return;
        }

        double xTranslationDistance = deltaX * XTranslationFactor;
        double yTranslationDistance = -deltaY * YTranslationFactor;

        //
        // Build transforms
        //
        translate.set(xTranslationDistance, yTranslationDistance, 0.0);
        transform1.set(translate);

        // Get and save the current transform
        subjectTransformGroup.getTransform(currentTransform);

        // Translate as needed
        currentTransform.mul(transform1, currentTransform);

        // Update the transform group
        subjectTransformGroup.setTransform(currentTransform);

        previousX = x;
        previousY = y;
    }

    /**
     * Respond to an elapsed frames event (assuming subclass has set up a wakeup
     * criterion for it).
     * 
     * @param time
     *            A WakeupOnElapsedFrames criterion to respond to.
     */
    public void onElapsedFrames(WakeupOnElapsedFrames timeEvent) {
        // Can't happen
    }
}

/*
 * 
 * Copyright (c) 1998 David R. Nadeau
 *  
 */

/**
 * WalkViewerBehavior is a utility class that creates a "walking style"
 * navigation symantic.
 * 
 * The behavior wakes up on mouse button presses, releases, and mouse movements
 * and generates transforms in a "walk style" that enables the user to walk
 * through a scene, translating and turning about as if they are within the
 * scene. Such a walk style is similar to the "Walk" navigation type used by
 * VRML browsers.
 * <P>
 * The behavior maps mouse drags to different transforms depending upon the
 * mouse button held down:
 * <DL>
 * <DT>Button 1 (left)
 * <DD>Horizontal movement --> Y-axis rotation
 * <DD>Vertical movement --> Z-axis translation
 * 
 * <DT>Button 2 (middle)
 * <DD>Horizontal movement --> Y-axis rotation
 * <DD>Vertical movement --> X-axis rotation
 * 
 * <DT>Button 3 (right)
 * <DD>Horizontal movement --> X-axis translation
 * <DD>Vertical movement --> Y-axis translation
 * </DL>
 * 
 * To support systems with 2 or 1 mouse buttons, the following alternate
 * mappings are supported while dragging with any mouse button held down and
 * zero or more keyboard modifiers held down:
 * <UL>
 * <LI>No modifiers = Button 1
 * <LI>ALT = Button 2
 * <LI>Meta = Button 3
 * <LI>Control = Button 3
 * </UL>
 * The behavior automatically modifies a TransformGroup provided to the
 * constructor. The TransformGroup's transform can be set at any time by the
 * application or other behaviors to cause the walk rotation and translation to
 * be reset.
 * <P>
 * While a mouse button is down, the behavior automatically changes the cursor
 * in a given parent AWT Component. If no parent Component is given, no cursor
 * changes are attempted.
 * 
 * @version 1.0, 98/04/16
 * @author David R. Nadeau, San Diego Supercomputer Center
 */

class WalkViewerBehavior extends ViewerBehavior {
    // This class is inspired by the MouseBehavior, MouseRotate,
    // MouseTranslate, and MouseZoom utility behaviors provided with
    // Java 3D. This class differs from those utilities in that it:
    //
    //    (a) encapsulates all three behaviors into one in order to
    //        enforce a specific "Walk" symantic
    //
    //    (b) supports set/get of the rotation and translation factors
    //        that control the speed of movement.
    //
    //    (c) supports the "Control" modifier as an alternative to the
    //        "Meta" modifier not present on PC, Mac, and most non-Sun
    //        keyboards. This makes button3 behavior usable on PCs,
    //        Macs, and other systems with fewer than 3 mouse buttons.

    // Previous and initial cursor locations
    protected int previousX = 0;

    protected int previousY = 0;

    protected int initialX = 0;

    protected int initialY = 0;

    // Deadzone size (delta from initial XY for which no
    // translate or rotate action is taken
    protected static final int DELTAX_DEADZONE = 10;

    protected static final int DELTAY_DEADZONE = 10;

    // Keep a set of wakeup criterion for animation-generated
    // event types.
    protected WakeupCriterion[] mouseAndAnimationEvents = null;

    protected WakeupOr mouseAndAnimationCriterion = null;

    protected WakeupOr savedMouseCriterion = null;

    // Saved standard cursor
    protected Cursor savedCursor = null;

    /**
     * Default Rotation and translation scaling factors for animated movements
     * (Button 1 press).
     */
    public static final double DEFAULT_YROTATION_ANIMATION_FACTOR = 0.0002;

    public static final double DEFAULT_ZTRANSLATION_ANIMATION_FACTOR = 0.01;

    protected double YRotationAnimationFactor = DEFAULT_YROTATION_ANIMATION_FACTOR;

    protected double ZTranslationAnimationFactor = DEFAULT_ZTRANSLATION_ANIMATION_FACTOR;

    /**
     * Constructs a new walk behavior that converts mouse actions into rotations
     * and translations. Rotations and translations are written into a
     * TransformGroup that must be set using the setTransformGroup method. The
     * cursor will be changed during mouse actions if the parent frame is set
     * using the setParentComponent method.
     * 
     * @return a new WalkViewerBehavior that needs its TransformGroup and parent
     *         Component set
     */
    public WalkViewerBehavior() {
        super();
    }

    /**
     * Constructs a new walk behavior that converts mouse actions into rotations
     * and translations. Rotations and translations are written into a
     * TransformGroup that must be set using the setTransformGroup method. The
     * cursor will be changed within the given AWT parent Component during mouse
     * drags.
     * 
     * @param parent
     *            a parent AWT Component within which the cursor will change
     *            during mouse drags
     * 
     * @return a new WalkViewerBehavior that needs its TransformGroup and parent
     *         Component set
     */
    public WalkViewerBehavior(Component parent) {
        super(parent);
    }

    /**
     * Constructs a new walk behavior that converts mouse actions into rotations
     * and translations. Rotations and translations are written into the given
     * TransformGroup. The cursor will be changed during mouse actions if the
     * parent frame is set using the setParentComponent method.
     * 
     * @param transformGroup
     *            a TransformGroup whos transform is read and written by the
     *            behavior
     * 
     * @return a new WalkViewerBehavior that needs its TransformGroup and parent
     *         Component set
     */
    public WalkViewerBehavior(TransformGroup transformGroup) {
        super();
        subjectTransformGroup = transformGroup;
    }

    /**
     * Constructs a new walk behavior that converts mouse actions into rotations
     * and translations. Rotations and translations are written into the given
     * TransformGroup. The cursor will be changed within the given AWT parent
     * Component during mouse drags.
     * 
     * @param transformGroup
     *            a TransformGroup whos transform is read and written by the
     *            behavior
     * 
     * @param parent
     *            a parent AWT Component within which the cursor will change
     *            during mouse drags
     * 
     * @return a new WalkViewerBehavior that needs its TransformGroup and parent
     *         Component set
     */
    public WalkViewerBehavior(TransformGroup transformGroup, Component parent) {
        super(parent);
        subjectTransformGroup = transformGroup;
    }

    /**
     * Initializes the behavior.
     */
    public void initialize() {
        super.initialize();
        savedMouseCriterion = mouseCriterion; // from parent class
        mouseAndAnimationEvents = new WakeupCriterion[4];
        mouseAndAnimationEvents[0] = new WakeupOnAWTEvent(MouseEvent.MOUSE_DRAGGED);
        mouseAndAnimationEvents[1] = new WakeupOnAWTEvent(MouseEvent.MOUSE_PRESSED);
        mouseAndAnimationEvents[2] = new WakeupOnAWTEvent(MouseEvent.MOUSE_RELEASED);
        mouseAndAnimationEvents[3] = new WakeupOnElapsedFrames(0);
        mouseAndAnimationCriterion = new WakeupOr(mouseAndAnimationEvents);
        // Don't use the above criterion until a button 1 down event
    }

    /**
     * Sets the Y rotation animation scaling factor for Y-axis rotations. This
     * scaling factor is used to control the speed of Y rotation when button 1
     * is pressed and dragged.
     * 
     * @param factor
     *            the double Y rotation scaling factor
     */
    public void setYRotationAnimationFactor(double factor) {
        YRotationAnimationFactor = factor;
    }

    /**
     * Gets the current Y animation rotation scaling factor for Y-axis
     * rotations.
     * 
     * @return the double Y rotation scaling factor
     */
    public double getYRotationAnimationFactor() {
        return YRotationAnimationFactor;
    }

    /**
     * Sets the Z animation translation scaling factor for Z-axis translations.
     * This scaling factor is used to control the speed of Z translation when
     * button 1 is pressed and dragged.
     * 
     * @param factor
     *            the double Z translation scaling factor
     */
    public void setZTranslationAnimationFactor(double factor) {
        ZTranslationAnimationFactor = factor;
    }

    /**
     * Gets the current Z animation translation scaling factor for Z-axis
     * translations.
     * 
     * @return the double Z translation scaling factor
     */
    public double getZTranslationAnimationFactor() {
        return ZTranslationAnimationFactor;
    }

    /**
     * Responds to an elapsed frames event. Such an event is generated on every
     * frame while button 1 is held down. On each call, this method computes new
     * Y-axis rotation and Z-axis translation values and writes them to the
     * behavior's TransformGroup. The translation and rotation amounts are
     * computed based upon the distance between the current cursor location and
     * the cursor location when button 1 was pressed. As this distance
     * increases, the translation or rotation amount increases.
     * 
     * @param time
     *            the WakeupOnElapsedFrames criterion to respond to
     */
    public void onElapsedFrames(WakeupOnElapsedFrames timeEvent) {
        //
        // Time elapsed while button down: create a rotation and
        // a translation.
        //
        // Compute the delta in X and Y from the initial position to
        // the previous position. Multiply the delta times a scaling
        // factor to compute an offset to add to the current translation
        // and rotation. Use the mapping:
        //
        //   positive X mouse delta --> negative Y-axis rotation
        //   positive Y mouse delta --> positive Z-axis translation
        //
        // where positive X mouse movement is to the right, and
        // positive Y mouse movement is **down** the screen.
        //
        if (buttonPressed != BUTTON1)
            return;
        int deltaX = previousX - initialX;
        int deltaY = previousY - initialY;

        double yRotationAngle = -deltaX * YRotationAnimationFactor;
        double zTranslationDistance = deltaY * ZTranslationAnimationFactor;

        //
        // Build transforms
        //
        transform1.rotY(yRotationAngle);
        translate.set(0.0, 0.0, zTranslationDistance);

        // Get and save the current transform matrix
        subjectTransformGroup.getTransform(currentTransform);
        currentTransform.get(matrix);

        // Translate to the origin, rotate, then translate back
        currentTransform.setTranslation(origin);
        currentTransform.mul(transform1, currentTransform);

        // Translate back from the origin by the original translation
        // distance, plus the new walk translation... but force walk
        // to travel on a plane by ignoring the Y component of a
        // transformed translation vector.
        currentTransform.transform(translate);
        translate.x += matrix.m03; // add in existing X translation
        translate.y = matrix.m13; // use Y translation
        translate.z += matrix.m23; // add in existing Z translation
        currentTransform.setTranslation(translate);

        // Update the transform group
        subjectTransformGroup.setTransform(currentTransform);
    }

    /**
     * Responds to a button1 event (press, release, or drag). On a press, the
     * method adds a wakeup criterion to the behavior's set, callling for the
     * behavior to be awoken on each frame. On a button prelease, this criterion
     * is removed from the set.
     * 
     * @param mouseEvent
     *            the MouseEvent to respond to
     */
    public void onButton1(MouseEvent mev) {
        if (subjectTransformGroup == null)
            return;

        int x = mev.getX();
        int y = mev.getY();

        if (mev.getID() == MouseEvent.MOUSE_PRESSED) {
            // Mouse button pressed: record position and change
            // the wakeup criterion to include elapsed time wakeups
            // so we can animate.
            previousX = x;
            previousY = y;
            initialX = x;
            initialY = y;

            // Swap criterion... parent class will not reschedule us
            mouseCriterion = mouseAndAnimationCriterion;

            // Change to a "move" cursor
            if (parentComponent != null) {
                savedCursor = parentComponent.getCursor();
                parentComponent.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
            }
            return;
        }
        if (mev.getID() == MouseEvent.MOUSE_RELEASED) {
            // Mouse button released: restore original wakeup
            // criterion which only includes mouse activity, not
            // elapsed time
            mouseCriterion = savedMouseCriterion;

            // Switch the cursor back
            if (parentComponent != null)
                parentComponent.setCursor(savedCursor);
            return;
        }

        previousX = x;
        previousY = y;
    }

    /**
     * Responds to a button2 event (press, release, or drag). On a press, the
     * method records the initial cursor location. On a drag, the difference
     * between the current and previous cursor location provides a delta that
     * controls the amount by which to rotate in X and Y.
     * 
     * @param mouseEvent
     *            the MouseEvent to respond to
     */
    public void onButton2(MouseEvent mev) {
        if (subjectTransformGroup == null)
            return;

        int x = mev.getX();
        int y = mev.getY();

        if (mev.getID() == MouseEvent.MOUSE_PRESSED) {
            // Mouse button pressed: record position
            previousX = x;
            previousY = y;
            initialX = x;
            initialY = y;

            // Change to a "rotate" cursor
            if (parentComponent != null) {
                savedCursor = parentComponent.getCursor();
                parentComponent.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
            }
            return;
        }
        if (mev.getID() == MouseEvent.MOUSE_RELEASED) {
            // Mouse button released: do nothing

            // Switch the cursor back
            if (parentComponent != null)
                parentComponent.setCursor(savedCursor);
            return;
        }

        //
        // Mouse moved while button down: create a rotation
        //
        // Compute the delta in X and Y from the previous
        // position. Use the delta to compute rotation
        // angles with the mapping:
        //
        //   positive X mouse delta --> negative Y-axis rotation
        //   positive Y mouse delta --> negative X-axis rotation
        //
        // where positive X mouse movement is to the right, and
        // positive Y mouse movement is **down** the screen.
        //
        int deltaX = x - previousX;
        int deltaY = 0;

        if (Math.abs(y - initialY) > DELTAY_DEADZONE) {
            // Cursor has moved far enough vertically to consider
            // it intentional, so get it's delta.
            deltaY = y - previousY;
        }

        if (deltaX > UNUSUAL_XDELTA || deltaX < -UNUSUAL_XDELTA || deltaY > UNUSUAL_YDELTA
                || deltaY < -UNUSUAL_YDELTA) {
            // Deltas are too huge to be believable. Probably a glitch.
            // Don't record the new XY location, or do anything.
            return;
        }

        double xRotationAngle = -deltaY * XRotationFactor;
        double yRotationAngle = -deltaX * YRotationFactor;

        //
        // Build transforms
        //
        transform1.rotX(xRotationAngle);
        transform2.rotY(yRotationAngle);

        // Get and save the current transform matrix
        subjectTransformGroup.getTransform(currentTransform);
        currentTransform.get(matrix);
        translate.set(matrix.m03, matrix.m13, matrix.m23);

        // Translate to the origin, rotate, then translate back
        currentTransform.setTranslation(origin);
        currentTransform.mul(transform2, currentTransform);
        currentTransform.mul(transform1);
        currentTransform.setTranslation(translate);

        // Update the transform group
        subjectTransformGroup.setTransform(currentTransform);

        previousX = x;
        previousY = y;
    }

    /**
     * Responds to a button3 event (press, release, or drag). On a drag, the
     * difference between the current and previous cursor location provides a
     * delta that controls the amount by which to translate in X and Y.
     * 
     * @param mouseEvent
     *            the MouseEvent to respond to
     */
    public void onButton3(MouseEvent mev) {
        if (subjectTransformGroup == null)
            return;

        int x = mev.getX();
        int y = mev.getY();

        if (mev.getID() == MouseEvent.MOUSE_PRESSED) {
            // Mouse button pressed: record position
            previousX = x;
            previousY = y;

            // Change to a "move" cursor
            if (parentComponent != null) {
                savedCursor = parentComponent.getCursor();
                parentComponent.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
            }
            return;
        }
        if (mev.getID() == MouseEvent.MOUSE_RELEASED) {
            // Mouse button released: do nothing

            // Switch the cursor back
            if (parentComponent != null)
                parentComponent.setCursor(savedCursor);
            return;
        }

        //
        // Mouse moved while button down: create a translation
        //
        // Compute the delta in X and Y from the previous
        // position. Use the delta to compute translation
        // distances with the mapping:
        //
        //   positive X mouse delta --> positive X-axis translation
        //   positive Y mouse delta --> negative Y-axis translation
        //
        // where positive X mouse movement is to the right, and
        // positive Y mouse movement is **down** the screen.
        //
        int deltaX = x - previousX;
        int deltaY = y - previousY;

        if (deltaX > UNUSUAL_XDELTA || deltaX < -UNUSUAL_XDELTA || deltaY > UNUSUAL_YDELTA
                || deltaY < -UNUSUAL_YDELTA) {
            // Deltas are too huge to be believable. Probably a glitch.
            // Don't record the new XY location, or do anything.
            return;
        }

        double xTranslationDistance = deltaX * XTranslationFactor;
        double yTranslationDistance = -deltaY * YTranslationFactor;

        //
        // Build transforms
        //
        translate.set(xTranslationDistance, yTranslationDistance, 0.0);
        transform1.set(translate);

        // Get and save the current transform
        subjectTransformGroup.getTransform(currentTransform);

        // Translate as needed
        currentTransform.mul(transform1);

        // Update the transform group
        subjectTransformGroup.setTransform(currentTransform);

        previousX = x;
        previousY = y;
    }
}

//
//CLASS
//CheckboxMenu - build a menu of grouped checkboxes
//
//DESCRIPTION
//The class creates a menu with one or more CheckboxMenuItem's
//and monitors that menu. When a menu checkbox is picked, the
//previous one is turned off (in radio-button style). Then,
//a given listener's checkboxChanged method is called, passing it
//the menu and the item checked.
//

class CheckboxMenu extends Menu implements ItemListener {
    // State
    protected CheckboxMenuItem[] checks = null;

    protected int current = 0;

    protected CheckboxMenuListener listener = null;

    //  Construct
    public CheckboxMenu(String name, NameValue[] items, CheckboxMenuListener listen) {
        this(name, items, 0, listen);
    }

    public CheckboxMenu(String name, NameValue[] items, int cur, CheckboxMenuListener listen) {
        super(name);
        current = cur;
        listener = listen;

        if (items == null)
            return;

        checks = new CheckboxMenuItem[items.length];
        for (int i = 0; i < items.length; i++) {
            checks[i] = new CheckboxMenuItem(items[i].name, false);
            checks[i].addItemListener(this);
            add(checks[i]);
        }
        checks[cur].setState(true);
    }

    //  Handle checkbox changed events
    public void itemStateChanged(ItemEvent event) {
        Object src = event.getSource();

        for (int i = 0; i < checks.length; i++) {
            if (src == checks[i]) {
                // Update the checkboxes
                checks[current].setState(false);
                current = i;
                checks[current].setState(true);

                if (listener != null)
                    listener.checkboxChanged(this, i);
                return;
            }
        }
    }

    // Methods to get and set state
    public int getCurrent() {
        return current;
    }

    public void setCurrent(int cur) {
        if (cur < 0 || cur >= checks.length)
            return; // ignore out of range choices
        if (checks == null)
            return;
        checks[current].setState(false);
        current = cur;
        checks[current].setState(true);
    }

    public CheckboxMenuItem getSelectedCheckbox() {
        if (checks == null)
            return null;
        return checks[current];
    }

    public void setSelectedCheckbox(CheckboxMenuItem item) {
        if (checks == null)
            return;
        for (int i = 0; i < checks.length; i++) {
            if (item == checks[i]) {
                checks[i].setState(false);
                current = i;
                checks[i].setState(true);
            }
        }
    }
}

/**
 * ViewerBehavior
 * 
 * @version 1.0, 98/04/16
 */

/**
 * Wakeup on mouse button presses, releases, and mouse movements and generate
 * transforms for a transform group. Classes that extend this class impose
 * specific symantics, such as "Examine" or "Walk" viewing, similar to the
 * navigation types used by VRML browsers.
 * 
 * To support systems with 2 or 1 mouse buttons, the following alternate
 * mappings are supported while dragging with any mouse button held down and
 * zero or more keyboard modifiers held down:
 * 
 * No modifiers = Button 1 ALT = Button 2 Meta = Button 3 Control = Button 3
 * 
 * The behavior automatically modifies a TransformGroup provided to the
 * constructor. The TransformGroup's transform can be set at any time by the
 * application or other behaviors to cause the viewer's rotation and translation
 * to be reset.
 */

// This class is inspired by the MouseBehavior, MouseRotate,
// MouseTranslate, and MouseZoom utility behaviors provided with
// Java 3D. This class differs from those utilities in that it:
//
//    (a) encapsulates all three behaviors into one in order to
//        enforce a specific viewing symantic
//
//    (b) supports set/get of the rotation and translation factors
//        that control the speed of movement.
//
//    (c) supports the "Control" modifier as an alternative to the
//        "Meta" modifier not present on PC, Mac, and most non-Sun
//        keyboards. This makes button3 behavior usable on PCs,
//        Macs, and other systems with fewer than 3 mouse buttons.

abstract class ViewerBehavior extends Behavior {
    // Keep track of the transform group who's transform we modify
    // during mouse motion.
    protected TransformGroup subjectTransformGroup = null;

    // Keep a set of wakeup criterion for different mouse-generated
    // event types.
    protected WakeupCriterion[] mouseEvents = null;

    protected WakeupOr mouseCriterion = null;

    // Track which button was last pressed
    protected static final int BUTTONNONE = -1;

    protected static final int BUTTON1 = 0;

    protected static final int BUTTON2 = 1;

    protected static final int BUTTON3 = 2;

    protected int buttonPressed = BUTTONNONE;

    // Keep a few Transform3Ds for use during event processing. This
    // avoids having to allocate new ones on each event.
    protected Transform3D currentTransform = new Transform3D();

    protected Transform3D transform1 = new Transform3D();

    protected Transform3D transform2 = new Transform3D();

    protected Matrix4d matrix = new Matrix4d();

    protected Vector3d origin = new Vector3d(0.0, 0.0, 0.0);

    protected Vector3d translate = new Vector3d(0.0, 0.0, 0.0);

    // Unusual X and Y delta limits.
    protected static final int UNUSUAL_XDELTA = 400;

    protected static final int UNUSUAL_YDELTA = 400;

    protected Component parentComponent = null;

    /**
     * Construct a viewer behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into a
     * transform group given later with the setTransformGroup( ) method.
     */
    public ViewerBehavior() {
        super();
    }

    /**
     * Construct a viewer behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into a
     * transform group given later with the setTransformGroup( ) method.
     * 
     * @param parent
     *            The AWT Component that contains the area generating mouse
     *            events.
     */
    public ViewerBehavior(Component parent) {
        super();
        parentComponent = parent;
    }

    /**
     * Construct a viewer behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into the
     * given transform group.
     * 
     * @param transformGroup
     *            The transform group to be modified by the behavior.
     */
    public ViewerBehavior(TransformGroup transformGroup) {
        super();
        subjectTransformGroup = transformGroup;
    }

    /**
     * Construct a viewer behavior that listens to mouse movement and button
     * presses to generate rotation and translation transforms written into the
     * given transform group.
     * 
     * @param transformGroup
     *            The transform group to be modified by the behavior.
     * @param parent
     *            The AWT Component that contains the area generating mouse
     *            events.
     */
    public ViewerBehavior(TransformGroup transformGroup, Component parent) {
        super();
        subjectTransformGroup = transformGroup;
        parentComponent = parent;
    }

    /**
     * Set the transform group modified by the viewer behavior. Setting the
     * transform group to null disables the behavior until the transform group
     * is again set to an existing group.
     * 
     * @param transformGroup
     *            The new transform group to be modified by the behavior.
     */
    public void setTransformGroup(TransformGroup transformGroup) {
        subjectTransformGroup = transformGroup;
    }

    /**
     * Get the transform group modified by the viewer behavior.
     */
    public TransformGroup getTransformGroup() {
        return subjectTransformGroup;
    }

    /**
     * Sets the parent component who's cursor will be changed during mouse
     * drags. If no component is given is given to the constructor, or set via
     * this method, no cursor changes will be done.
     * 
     * @param parent
     *            the AWT Component, such as a Frame, within which cursor
     *            changes should take place during mouse drags
     */
    public void setParentComponent(Component parent) {
        parentComponent = parent;
    }

    /*
     * Gets the parent frame within which the cursor changes during mouse drags.
     * 
     * @return the AWT Component, such as a Frame, within which cursor changes
     * should take place during mouse drags. Returns null if no parent is set.
     */
    public Component getParentComponent() {
        return parentComponent;
    }

    /**
     * Initialize the behavior.
     */
    public void initialize() {
        // Wakeup when the mouse is dragged or when a mouse button
        // is pressed or released.
        mouseEvents = new WakeupCriterion[3];
        mouseEvents[0] = new WakeupOnAWTEvent(MouseEvent.MOUSE_DRAGGED);
        mouseEvents[1] = new WakeupOnAWTEvent(MouseEvent.MOUSE_PRESSED);
        mouseEvents[2] = new WakeupOnAWTEvent(MouseEvent.MOUSE_RELEASED);
        mouseCriterion = new WakeupOr(mouseEvents);
        wakeupOn(mouseCriterion);
    }

    /**
     * Process a new wakeup. Interpret mouse button presses, releases, and mouse
     * drags.
     * 
     * @param criteria
     *            The wakeup criteria causing the behavior wakeup.
     */
    public void processStimulus(Enumeration criteria) {
        WakeupCriterion wakeup = null;
        AWTEvent[] event = null;
        int whichButton = BUTTONNONE;

        // Process all pending wakeups
        while (criteria.hasMoreElements()) {
            wakeup = (WakeupCriterion) criteria.nextElement();
            if (wakeup instanceof WakeupOnAWTEvent) {
                event = ((WakeupOnAWTEvent) wakeup).getAWTEvent();

                // Process all pending events
                for (int i = 0; i < event.length; i++) {
                    if (event[i].getID() != MouseEvent.MOUSE_PRESSED
                            && event[i].getID() != MouseEvent.MOUSE_RELEASED
                            && event[i].getID() != MouseEvent.MOUSE_DRAGGED)
                        // Ignore uninteresting mouse events
                        continue;

                    //
                    // Regretably, Java event handling (or perhaps
                    // underlying OS event handling) doesn't always
                    // catch button bounces (redundant presses and
                    // releases), or order events so that the last
                    // drag event is delivered before a release.
                    // This means we can get stray events that we
                    // filter out here.
                    //
                    if (event[i].getID() == MouseEvent.MOUSE_PRESSED && buttonPressed != BUTTONNONE)
                        // Ignore additional button presses until a release
                        continue;

                    if (event[i].getID() == MouseEvent.MOUSE_RELEASED && buttonPressed == BUTTONNONE)
                        // Ignore additional button releases until a press
                        continue;

                    if (event[i].getID() == MouseEvent.MOUSE_DRAGGED && buttonPressed == BUTTONNONE)
                        // Ignore drags until a press
                        continue;

                    MouseEvent mev = (MouseEvent) event[i];
                    int modifiers = mev.getModifiers();

                    //
                    // Unfortunately, the underlying event handling
                    // doesn't do a "grab" operation when a mouse button
                    // is pressed. This means that once a button is
                    // pressed, if another mouse button or a keyboard
                    // modifier key is pressed, the delivered mouse event
                    // will show that a different button is being held
                    // down. For instance:
                    //
                    // Action Event
                    //  Button 1 press Button 1 press
                    //  Drag with button 1 down Button 1 drag
                    //  ALT press -
                    //  Drag with ALT & button 1 down Button 2 drag
                    //  Button 1 release Button 2 release
                    //
                    // The upshot is that we can get a button press
                    // without a matching release, and the button
                    // associated with a drag can change mid-drag.
                    //
                    // To fix this, we watch for an initial button
                    // press, and thenceforth consider that button
                    // to be the one held down, even if additional
                    // buttons get pressed, and despite what is
                    // reported in the event. Only when a button is
                    // released, do we end such a grab.
                    //

                    if (buttonPressed == BUTTONNONE) {
                        // No button is pressed yet, figure out which
                        // button is down now and how to direct events
                        if (((modifiers & InputEvent.BUTTON3_MASK) != 0)
                                || (((modifiers & InputEvent.BUTTON1_MASK) != 0)
                                        && ((modifiers & InputEvent.CTRL_MASK) == InputEvent.CTRL_MASK))) {
                            // Button 3 activity (META or CTRL down)
                            whichButton = BUTTON3;
                        } else if ((modifiers & InputEvent.BUTTON2_MASK) != 0) {
                            // Button 2 activity (ALT down)
                            whichButton = BUTTON2;
                        } else {
                            // Button 1 activity (no modifiers down)
                            whichButton = BUTTON1;
                        }

                        // If the event is to press a button, then
                        // record that that button is now down
                        if (event[i].getID() == MouseEvent.MOUSE_PRESSED)
                            buttonPressed = whichButton;
                    } else {
                        // Otherwise a button was pressed earlier and
                        // hasn't been released yet. Assign all further
                        // events to it, even if ALT, META, CTRL, or
                        // another button has been pressed as well.
                        whichButton = buttonPressed;
                    }

                    // Distribute the event
                    switch (whichButton) {
                    case BUTTON1:
                        onButton1(mev);
                        break;
                    case BUTTON2:
                        onButton2(mev);
                        break;
                    case BUTTON3:
                        onButton3(mev);
                        break;
                    default:
                        break;
                    }

                    // If the event is to release a button, then
                    // record that that button is now up
                    if (event[i].getID() == MouseEvent.MOUSE_RELEASED)
                        buttonPressed = BUTTONNONE;
                }
                continue;
            }

            if (wakeup instanceof WakeupOnElapsedFrames) {
                onElapsedFrames((WakeupOnElapsedFrames) wakeup);
                continue;
            }
        }

        // Reschedule us for another wakeup
        wakeupOn(mouseCriterion);
    }

    /**
     * Default X and Y rotation factors, and XYZ translation factors.
     */
    public static final double DEFAULT_XROTATION_FACTOR = 0.02;

    public static final double DEFAULT_YROTATION_FACTOR = 0.005;

    public static final double DEFAULT_XTRANSLATION_FACTOR = 0.02;

    public static final double DEFAULT_YTRANSLATION_FACTOR = 0.02;

    public static final double DEFAULT_ZTRANSLATION_FACTOR = 0.04;

    protected double XRotationFactor = DEFAULT_XROTATION_FACTOR;

    protected double YRotationFactor = DEFAULT_YROTATION_FACTOR;

    protected double XTranslationFactor = DEFAULT_XTRANSLATION_FACTOR;

    protected double YTranslationFactor = DEFAULT_YTRANSLATION_FACTOR;

    protected double ZTranslationFactor = DEFAULT_ZTRANSLATION_FACTOR;

    /**
     * Set the X rotation scaling factor for X-axis rotations.
     * 
     * @param factor
     *            The new scaling factor.
     */
    public void setXRotationFactor(double factor) {
        XRotationFactor = factor;
    }

    /**
     * Get the current X rotation scaling factor for X-axis rotations.
     */
    public double getXRotationFactor() {
        return XRotationFactor;
    }

    /**
     * Set the Y rotation scaling factor for Y-axis rotations.
     * 
     * @param factor
     *            The new scaling factor.
     */
    public void setYRotationFactor(double factor) {
        YRotationFactor = factor;
    }

    /**
     * Get the current Y rotation scaling factor for Y-axis rotations.
     */
    public double getYRotationFactor() {
        return YRotationFactor;
    }

    /**
     * Set the X translation scaling factor for X-axis translations.
     * 
     * @param factor
     *            The new scaling factor.
     */
    public void setXTranslationFactor(double factor) {
        XTranslationFactor = factor;
    }

    /**
     * Get the current X translation scaling factor for X-axis translations.
     */
    public double getXTranslationFactor() {
        return XTranslationFactor;
    }

    /**
     * Set the Y translation scaling factor for Y-axis translations.
     * 
     * @param factor
     *            The new scaling factor.
     */
    public void setYTranslationFactor(double factor) {
        YTranslationFactor = factor;
    }

    /**
     * Get the current Y translation scaling factor for Y-axis translations.
     */
    public double getYTranslationFactor() {
        return YTranslationFactor;
    }

    /**
     * Set the Z translation scaling factor for Z-axis translations.
     * 
     * @param factor
     *            The new scaling factor.
     */
    public void setZTranslationFactor(double factor) {
        ZTranslationFactor = factor;
    }

    /**
     * Get the current Z translation scaling factor for Z-axis translations.
     */
    public double getZTranslationFactor() {
        return ZTranslationFactor;
    }

    /**
     * Respond to a button1 event (press, release, or drag).
     * 
     * @param mouseEvent
     *            A MouseEvent to respond to.
     */
    public abstract void onButton1(MouseEvent mouseEvent);

    /**
     * Respond to a button2 event (press, release, or drag).
     * 
     * @param mouseEvent
     *            A MouseEvent to respond to.
     */
    public abstract void onButton2(MouseEvent mouseEvent);

    /**
     * Responed to a button3 event (press, release, or drag).
     * 
     * @param mouseEvent
     *            A MouseEvent to respond to.
     */
    public abstract void onButton3(MouseEvent mouseEvent);

    /**
     * Respond to an elapsed frames event (assuming subclass has set up a wakeup
     * criterion for it).
     * 
     * @param time
     *            A WakeupOnElapsedFrames criterion to respond to.
     */
    public abstract void onElapsedFrames(WakeupOnElapsedFrames timeEvent);
}

//
//CLASS
//NameValue - create a handy name-value pair
//
//DESCRIPTION
//It is frequently handy to have one or more name-value pairs
//with which to store named colors, named positions, named textures,
//and so forth. Several of the examples use this class.
//
//AUTHOR
//David R. Nadeau / San Diego Supercomputer Center
//

class NameValue {
    public String name;

    public Object value;

    public NameValue(String n, Object v) {
        name = n;
        value = v;
    }
}