PickCollisionTest.java Source code

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Here is the source code for PickCollisionTest.java

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/**********************************************************
 Copyright (C) 2001    Daniel Selman
    
 First distributed with the book "Java 3D Programming"
 by Daniel Selman and published by Manning Publications.
 http://manning.com/selman
    
 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation, version 2.
    
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
    
 The license can be found on the WWW at:
 http://www.fsf.org/copyleft/gpl.html
    
 Or by writing to:
 Free Software Foundation, Inc.,
 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
    
 Authors can be contacted at:
 Daniel Selman: daniel@selman.org
    
 If you make changes you think others would like, please 
 contact one of the authors or someone at the 
 www.j3d.org web site.
 **************************************************************/

import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.GraphicsConfigTemplate;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;
import java.net.URL;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.Appearance;
import javax.media.j3d.AudioDevice;
import javax.media.j3d.Background;
import javax.media.j3d.Behavior;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.Bounds;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.DirectionalLight;
import javax.media.j3d.GraphicsConfigTemplate3D;
import javax.media.j3d.Group;
import javax.media.j3d.Locale;
import javax.media.j3d.Material;
import javax.media.j3d.Node;
import javax.media.j3d.PhysicalBody;
import javax.media.j3d.PhysicalEnvironment;
import javax.media.j3d.PickBounds;
import javax.media.j3d.PolygonAttributes;
import javax.media.j3d.SceneGraphObject;
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.media.j3d.WakeupCondition;
import javax.media.j3d.WakeupCriterion;
import javax.media.j3d.WakeupOnElapsedFrames;
import javax.media.j3d.WakeupOr;
import javax.vecmath.Color3f;
import javax.vecmath.Point3d;
import javax.vecmath.Vector3d;

import com.sun.j3d.audioengines.javasound.JavaSoundMixer;
import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.ColorCube;
import com.sun.j3d.utils.geometry.Sphere;
import com.sun.j3d.utils.picking.PickResult;
import com.sun.j3d.utils.picking.PickTool;

/**
 * This example creates a large hollow box (out of ColorCubes, one for each side
 * of the box). Within the box, four Spheres are created. Each Sphere has a
 * behavior attached which detects collisions with the sides of the box, and the
 * other Spheres. When a collision is detected the trajectory of the Sphere is
 * reversed and the color of the Sphere changed. When a collision is not
 * detected the Sphere is advanced along its current trajectory.
 */
public class PickCollisionTest extends Java3dApplet implements ActionListener {
    private static int m_kWidth = 400;

    private static int m_kHeight = 400;

    private static final int boxSize = 10;

    public PickCollisionTest() {
        initJava3d();
    }

    public void actionPerformed(ActionEvent event) {
    }

    protected double getScale() {
        return 0.5;
    }

    // method to recursively set the user data for objects in the scenegraph
    // tree
    // we also set the capabilites on Shape3D and Morph objects required by the
    // PickTool
    void recursiveSetUserData(SceneGraphObject root, Object value) {
        root.setUserData(value);

        // recursively process group
        if (root instanceof Group) {
            Group g = (Group) root;

            // recurse on child nodes
            java.util.Enumeration enumKids = g.getAllChildren();

            while (enumKids.hasMoreElements() != false)
                recursiveSetUserData((SceneGraphObject) enumKids.nextElement(), value);
        }
    }

    protected void addCube(BranchGroup bg, double x, double y, double z, double sx, double sy, double sz,
            String name, boolean wireframe) {
        // create four ColorCube objects
        TransformGroup cubeTg = new TransformGroup();
        Transform3D t3d = new Transform3D();
        t3d.setTranslation(new Vector3d(x, y, z));
        t3d.setScale(new Vector3d(sx, sy, sz));
        cubeTg.setTransform(t3d);
        ColorCube cube = new ColorCube(1.0);

        // we have to make the front face wireframe
        // or we can't see inside the box!
        if (wireframe) {
            Appearance app = new Appearance();
            app.setPolygonAttributes(
                    new PolygonAttributes(PolygonAttributes.POLYGON_LINE, PolygonAttributes.CULL_NONE, 0));
            cube.setAppearance(app);
        }

        cubeTg.addChild(cube);
        recursiveSetUserData(cubeTg, name);

        bg.addChild(cubeTg);
    }

    protected void addSphere(BranchGroup bg, double x, double y, double z, Vector3d incVector, String name) {
        Appearance app = new Appearance();

        TransformGroup sphereTg = new TransformGroup();
        Transform3D t3d = new Transform3D();
        t3d.setTranslation(new Vector3d(x, y, z));
        sphereTg.setTransform(t3d);

        sphereTg.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        sphereTg.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);

        sphereTg.addChild(new Sphere(1, app));
        bg.addChild(sphereTg);
        recursiveSetUserData(sphereTg, name);

        // create the collision behaviour
        CollisionBehavior collisionBehavior = new CollisionBehavior(bg, sphereTg, app, new Vector3d(x, y, z),
                incVector);
        collisionBehavior.setSchedulingBounds(getApplicationBounds());
        bg.addChild(collisionBehavior);
    }

    protected BranchGroup createSceneBranchGroup() {
        BranchGroup objRoot = super.createSceneBranchGroup();

        Bounds lightBounds = getApplicationBounds();

        AmbientLight ambLight = new AmbientLight(true, new Color3f(1.0f, 1.0f, 1.0f));
        ambLight.setInfluencingBounds(lightBounds);
        objRoot.addChild(ambLight);

        DirectionalLight headLight = new DirectionalLight();
        headLight.setInfluencingBounds(lightBounds);
        objRoot.addChild(headLight);

        // create ColorCube objects, one for each side of a cube
        addCube(objRoot, 0, boxSize, 0, boxSize, 0.1, boxSize, "Top", false);
        addCube(objRoot, 0, -boxSize, 0, boxSize, 0.1, boxSize, "Bottom", false);
        addCube(objRoot, boxSize, 0, 0, 0.1, boxSize, boxSize, "Right", false);
        addCube(objRoot, -boxSize, 0, 0, 0.1, boxSize, boxSize, "Left", false);
        addCube(objRoot, 0, 0, -boxSize, boxSize, boxSize, 0.1, "Back", false);
        addCube(objRoot, 0, 0, boxSize, boxSize, boxSize, 0.1, "Front", true);

        // create the spheres
        addSphere(objRoot, 0, 3, 4, new Vector3d(0.1, 0.3, 0.1), "Sphere 1");
        addSphere(objRoot, 3, 0, -2, new Vector3d(0.4, 0.1, 0.2), "Sphere 2");
        addSphere(objRoot, 0, -3, 0, new Vector3d(0.2, 0.2, 0.6), "Sphere 3");
        addSphere(objRoot, -3, 0, -4, new Vector3d(0.1, 0.6, 0.3), "Sphere 4");

        return objRoot;
    }

    public static void main(String[] args) {
        PickCollisionTest pickCollisionTest = new PickCollisionTest();
        pickCollisionTest.saveCommandLineArguments(args);

        new MainFrame(pickCollisionTest, m_kWidth, m_kHeight);
    }
}

/**
 * This behavior detects collisions between the branch of a scene, and a
 * collision object. The Java 3D 1.2 picking utilities are used to implement
 * collision detection. The objects in the scene that are collidable should have
 * their user data set. The collision object's user data is used to ignore
 * collisions between the object and itself.
 * 
 * When a collision is detected the trajectory of the collision object is
 * reversed (plus a small random factor) and an Appearance object is modified.
 * 
 * When a collision is not detected the collision object is moved along its
 * current trajectory and the Appearance color is reset.
 * 
 * Colision checking is run after every frame.
 *  
 */

class CollisionBehavior extends Behavior {
    // the wake up condition for the behavior
    protected WakeupCondition m_WakeupCondition = null;

    // how often we check for a collision
    private static final int ELAPSED_FRAME_COUNT = 1;

    // the branch that we check for collisions
    private BranchGroup pickRoot = null;

    // the collision object that we are controlling
    private TransformGroup collisionObject = null;

    // the appearance object that we are controlling
    private Appearance objectAppearance = null;

    // cached PickBounds object used for collision detection
    private PickBounds pickBounds = null;

    // cached Material objects that define the collided and missed colors
    private Material collideMaterial = null;

    private Material missMaterial = null;

    // the current trajectory of the object
    private Vector3d incrementVector = null;

    // the current position of the object
    private Vector3d positionVector = null;

    public CollisionBehavior(BranchGroup pickRoot, TransformGroup collisionObject, Appearance app,
            Vector3d posVector, Vector3d incVector) {
        // save references to the objects
        this.pickRoot = pickRoot;
        this.collisionObject = collisionObject;
        this.objectAppearance = app;

        incrementVector = incVector;
        positionVector = posVector;

        // create the WakeupCriterion for the behavior
        WakeupCriterion criterionArray[] = new WakeupCriterion[1];
        criterionArray[0] = new WakeupOnElapsedFrames(ELAPSED_FRAME_COUNT);

        objectAppearance.setCapability(Appearance.ALLOW_MATERIAL_WRITE);

        collisionObject.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        collisionObject.setCapability(Node.ALLOW_BOUNDS_READ);

        // save the WakeupCriterion for the behavior
        m_WakeupCondition = new WakeupOr(criterionArray);
    }

    public void initialize() {
        // apply the initial WakeupCriterion
        wakeupOn(m_WakeupCondition);

        Color3f objColor = new Color3f(1.0f, 0.1f, 0.2f);
        Color3f black = new Color3f(0.0f, 0.0f, 0.0f);
        collideMaterial = new Material(objColor, black, objColor, black, 80.0f);

        objColor = new Color3f(0.0f, 0.1f, 0.8f);
        missMaterial = new Material(objColor, black, objColor, black, 80.0f);

        objectAppearance.setMaterial(missMaterial);
    }

    protected void onCollide() {
        objectAppearance.setMaterial(collideMaterial);

        incrementVector.negate();

        // add a little randomness
        incrementVector.x += (Math.random() - 0.5) / 20.0;
        incrementVector.y += (Math.random() - 0.5) / 20.0;
        incrementVector.z += (Math.random() - 0.5) / 20.0;
    }

    protected void onMiss() {
        objectAppearance.setMaterial(missMaterial);
    }

    protected void moveCollisionObject() {
        Transform3D t3d = new Transform3D();

        positionVector.add(incrementVector);
        t3d.setTranslation(positionVector);

        collisionObject.setTransform(t3d);
    }

    public boolean isCollision(PickResult[] resultArray) {
        if (resultArray == null || resultArray.length == 0)
            return false;

        // we use the user data on the nodes to ignore the
        // case of the collisionObject having collided with itself!
        // the user data also gives us a good mechanism for reporting the
        // collisions.
        for (int n = 0; n < resultArray.length; n++) {
            Object userData = resultArray[n].getObject().getUserData();

            if (userData != null && userData instanceof String) {
                // check that we are not colliding with ourselves...
                if (((String) userData).equals((String) collisionObject.getUserData()) == false) {
                    System.out.println("Collision between: " + collisionObject.getUserData() + " and: " + userData);
                    return true;
                }
            }
        }

        return false;
    }

    public void processStimulus(java.util.Enumeration criteria) {
        while (criteria.hasMoreElements()) {
            WakeupCriterion wakeUp = (WakeupCriterion) criteria.nextElement();

            // every N frames, check for a collision
            if (wakeUp instanceof WakeupOnElapsedFrames) {
                // create a PickBounds
                PickTool pickTool = new PickTool(pickRoot);
                pickTool.setMode(PickTool.BOUNDS);

                BoundingSphere bounds = (BoundingSphere) collisionObject.getBounds();
                pickBounds = new PickBounds(new BoundingSphere(
                        new Point3d(positionVector.x, positionVector.y, positionVector.z), bounds.getRadius()));
                pickTool.setShape(pickBounds, new Point3d(0, 0, 0));
                PickResult[] resultArray = pickTool.pickAll();

                if (isCollision(resultArray))
                    onCollide();
                else
                    onMiss();

                moveCollisionObject();
            }
        }

        // assign the next WakeUpCondition, so we are notified again
        wakeupOn(m_WakeupCondition);
    }
}

/*******************************************************************************
 * Copyright (C) 2001 Daniel Selman
 * 
 * First distributed with the book "Java 3D Programming" by Daniel Selman and
 * published by Manning Publications. http://manning.com/selman
 * 
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License as published by the Free Software
 * Foundation, version 2.
 * 
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
 * details.
 * 
 * The license can be found on the WWW at: http://www.fsf.org/copyleft/gpl.html
 * 
 * Or by writing to: Free Software Foundation, Inc., 59 Temple Place - Suite
 * 330, Boston, MA 02111-1307, USA.
 * 
 * Authors can be contacted at: Daniel Selman: daniel@selman.org
 * 
 * If you make changes you think others would like, please contact one of the
 * authors or someone at the www.j3d.org web site.
 ******************************************************************************/

//*****************************************************************************
/**
 * Java3dApplet
 * 
 * Base class for defining a Java 3D applet. Contains some useful methods for
 * defining views and scenegraphs etc.
 * 
 * @author Daniel Selman
 * @version 1.0
 */
//*****************************************************************************

abstract class Java3dApplet extends Applet {
    public static int m_kWidth = 300;

    public static int m_kHeight = 300;

    protected String[] m_szCommandLineArray = null;

    protected VirtualUniverse m_Universe = null;

    protected BranchGroup m_SceneBranchGroup = null;

    protected Bounds m_ApplicationBounds = null;

    //   protected com.tornadolabs.j3dtree.Java3dTree m_Java3dTree = null;

    public Java3dApplet() {
    }

    public boolean isApplet() {
        try {
            System.getProperty("user.dir");
            System.out.println("Running as Application.");
            return false;
        } catch (Exception e) {
        }

        System.out.println("Running as Applet.");
        return true;
    }

    public URL getWorkingDirectory() throws java.net.MalformedURLException {
        URL url = null;

        try {
            File file = new File(System.getProperty("user.dir"));
            System.out.println("Running as Application:");
            System.out.println("   " + file.toURL());
            return file.toURL();
        } catch (Exception e) {
        }

        System.out.println("Running as Applet:");
        System.out.println("   " + getCodeBase());

        return getCodeBase();
    }

    public VirtualUniverse getVirtualUniverse() {
        return m_Universe;
    }

    //public com.tornadolabs.j3dtree.Java3dTree getJ3dTree() {
    //return m_Java3dTree;
    //   }

    public Locale getFirstLocale() {
        java.util.Enumeration e = m_Universe.getAllLocales();

        if (e.hasMoreElements() != false)
            return (Locale) e.nextElement();

        return null;
    }

    protected Bounds getApplicationBounds() {
        if (m_ApplicationBounds == null)
            m_ApplicationBounds = createApplicationBounds();

        return m_ApplicationBounds;
    }

    protected Bounds createApplicationBounds() {
        m_ApplicationBounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);
        return m_ApplicationBounds;
    }

    protected Background createBackground() {
        Background back = new Background(new Color3f(0.9f, 0.9f, 0.9f));
        back.setApplicationBounds(createApplicationBounds());
        return back;
    }

    public void initJava3d() {
        //   m_Java3dTree = new com.tornadolabs.j3dtree.Java3dTree();
        m_Universe = createVirtualUniverse();

        Locale locale = createLocale(m_Universe);

        BranchGroup sceneBranchGroup = createSceneBranchGroup();

        ViewPlatform vp = createViewPlatform();
        BranchGroup viewBranchGroup = createViewBranchGroup(getViewTransformGroupArray(), vp);

        createView(vp);

        Background background = createBackground();

        if (background != null)
            sceneBranchGroup.addChild(background);

        //      m_Java3dTree.recursiveApplyCapability(sceneBranchGroup);
        //   m_Java3dTree.recursiveApplyCapability(viewBranchGroup);

        locale.addBranchGraph(sceneBranchGroup);
        addViewBranchGroup(locale, viewBranchGroup);

        onDoneInit();
    }

    protected void onDoneInit() {
        //   m_Java3dTree.updateNodes(m_Universe);
    }

    protected double getScale() {
        return 1.0;
    }

    public TransformGroup[] getViewTransformGroupArray() {
        TransformGroup[] tgArray = new TransformGroup[1];
        tgArray[0] = new TransformGroup();

        // move the camera BACK a little...
        // note that we have to invert the matrix as
        // we are moving the viewer
        Transform3D t3d = new Transform3D();
        t3d.setScale(getScale());
        t3d.setTranslation(new Vector3d(0.0, 0.0, -20.0));
        t3d.invert();
        tgArray[0].setTransform(t3d);

        return tgArray;
    }

    protected void addViewBranchGroup(Locale locale, BranchGroup bg) {
        locale.addBranchGraph(bg);
    }

    protected Locale createLocale(VirtualUniverse u) {
        return new Locale(u);
    }

    protected BranchGroup createSceneBranchGroup() {
        m_SceneBranchGroup = new BranchGroup();
        return m_SceneBranchGroup;
    }

    protected View createView(ViewPlatform vp) {
        View view = new View();

        PhysicalBody pb = createPhysicalBody();
        PhysicalEnvironment pe = createPhysicalEnvironment();

        AudioDevice audioDevice = createAudioDevice(pe);

        if (audioDevice != null) {
            pe.setAudioDevice(audioDevice);
            audioDevice.initialize();
        }

        view.setPhysicalEnvironment(pe);
        view.setPhysicalBody(pb);

        if (vp != null)
            view.attachViewPlatform(vp);

        view.setBackClipDistance(getBackClipDistance());
        view.setFrontClipDistance(getFrontClipDistance());

        Canvas3D c3d = createCanvas3D();
        view.addCanvas3D(c3d);
        addCanvas3D(c3d);

        return view;
    }

    protected PhysicalBody createPhysicalBody() {
        return new PhysicalBody();
    }

    protected AudioDevice createAudioDevice(PhysicalEnvironment pe) {
        JavaSoundMixer javaSoundMixer = new JavaSoundMixer(pe);

        if (javaSoundMixer == null)
            System.out.println("create of audiodevice failed");

        return javaSoundMixer;
    }

    protected PhysicalEnvironment createPhysicalEnvironment() {
        return new PhysicalEnvironment();
    }

    protected float getViewPlatformActivationRadius() {
        return 100;
    }

    protected ViewPlatform createViewPlatform() {
        ViewPlatform vp = new ViewPlatform();
        vp.setViewAttachPolicy(View.RELATIVE_TO_FIELD_OF_VIEW);
        vp.setActivationRadius(getViewPlatformActivationRadius());

        return vp;
    }

    protected Canvas3D createCanvas3D() {
        GraphicsConfigTemplate3D gc3D = new GraphicsConfigTemplate3D();
        gc3D.setSceneAntialiasing(GraphicsConfigTemplate.PREFERRED);
        GraphicsDevice gd[] = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();

        Canvas3D c3d = new Canvas3D(gd[0].getBestConfiguration(gc3D));
        c3d.setSize(getCanvas3dWidth(c3d), getCanvas3dHeight(c3d));

        return c3d;
    }

    protected int getCanvas3dWidth(Canvas3D c3d) {
        return m_kWidth;
    }

    protected int getCanvas3dHeight(Canvas3D c3d) {
        return m_kHeight;
    }

    protected double getBackClipDistance() {
        return 100.0;
    }

    protected double getFrontClipDistance() {
        return 1.0;
    }

    protected BranchGroup createViewBranchGroup(TransformGroup[] tgArray, ViewPlatform vp) {
        BranchGroup vpBranchGroup = new BranchGroup();

        if (tgArray != null && tgArray.length > 0) {
            Group parentGroup = vpBranchGroup;
            TransformGroup curTg = null;

            for (int n = 0; n < tgArray.length; n++) {
                curTg = tgArray[n];
                parentGroup.addChild(curTg);
                parentGroup = curTg;
            }

            tgArray[tgArray.length - 1].addChild(vp);
        } else
            vpBranchGroup.addChild(vp);

        return vpBranchGroup;
    }

    protected void addCanvas3D(Canvas3D c3d) {
        setLayout(new BorderLayout());
        add(c3d, BorderLayout.CENTER);
        doLayout();
    }

    protected VirtualUniverse createVirtualUniverse() {
        return new VirtualUniverse();
    }

    protected void saveCommandLineArguments(String[] szArgs) {
        m_szCommandLineArray = szArgs;
    }

    protected String[] getCommandLineArguments() {
        return m_szCommandLineArray;
    }
}