SimpleBillboard.java Source code

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Here is the source code for SimpleBillboard.java

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/*
Essential Java 3D Fast
    
Ian Palmer
    
Publisher: Springer-Verlag
    
ISBN: 1-85233-394-4
    
*/
import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.Frame;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.Appearance;
import javax.media.j3d.Billboard;
import javax.media.j3d.BoundingLeaf;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.DirectionalLight;
import javax.media.j3d.Locale;
import javax.media.j3d.Material;
import javax.media.j3d.PhysicalBody;
import javax.media.j3d.PhysicalEnvironment;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.media.j3d.View;
import javax.media.j3d.ViewPlatform;
import javax.media.j3d.VirtualUniverse;
import javax.vecmath.Color3f;
import javax.vecmath.Point3d;
import javax.vecmath.Vector3d;
import javax.vecmath.Vector3f;

import com.sun.j3d.utils.behaviors.keyboard.KeyNavigatorBehavior;
import com.sun.j3d.utils.geometry.Box;
import com.sun.j3d.utils.geometry.ColorCube;

/**
 * This application demonstrates the use of a billboard node. Two cubes are
 * created, one yellow and the other with a a different colour on each face. The
 * billboard is created so that the red face of the right cube is always facing
 * the viewer. A key board utility class is used to allow modification of the
 * view angle.
 * 
 * @author I.J.Palmer
 * @version 1.0
 */
public class SimpleBillboard extends Frame implements ActionListener {
    protected Canvas3D myCanvas3D = new Canvas3D(null);

    protected Button exitButton = new Button("Exit");

    protected BoundingSphere bounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);

    /**
     * Build the view branch of the scene graph. In this case a key navigation
     * utility object is created and associated with the view transform so that
     * the view can be changed via the keyboard.
     * 
     * @return BranchGroup that is the root of the view branch
     */
    protected BranchGroup buildViewBranch(Canvas3D c) {
        BranchGroup viewBranch = new BranchGroup();
        Transform3D viewXfm = new Transform3D();
        viewXfm.set(new Vector3f(0.0f, 0.0f, 10.0f));
        TransformGroup viewXfmGroup = new TransformGroup(viewXfm);
        viewXfmGroup.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
        viewXfmGroup.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        BoundingSphere movingBounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);
        BoundingLeaf boundLeaf = new BoundingLeaf(movingBounds);
        ViewPlatform myViewPlatform = new ViewPlatform();
        viewXfmGroup.addChild(boundLeaf);
        PhysicalBody myBody = new PhysicalBody();
        PhysicalEnvironment myEnvironment = new PhysicalEnvironment();
        viewXfmGroup.addChild(myViewPlatform);
        viewBranch.addChild(viewXfmGroup);
        View myView = new View();
        myView.addCanvas3D(c);
        myView.attachViewPlatform(myViewPlatform);
        myView.setPhysicalBody(myBody);
        myView.setPhysicalEnvironment(myEnvironment);

        KeyNavigatorBehavior keyNav = new KeyNavigatorBehavior(viewXfmGroup);
        keyNav.setSchedulingBounds(movingBounds);
        viewBranch.addChild(keyNav);

        return viewBranch;
    }

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

    /**
     * Build the content branch for the scene graph. This creates two cubes and
     * uses a billboard node to keep one face of one of the cubes facing the
     * viewer.
     * 
     * @return BranchGroup that is the root of the content
     */
    protected BranchGroup buildContentBranch() {
        //Create the appearance
        Appearance app = new Appearance();
        Color3f ambientColour = new Color3f(1.0f, 1.0f, 0.0f);
        Color3f emissiveColour = new Color3f(0.0f, 0.0f, 0.0f);
        Color3f specularColour = new Color3f(1.0f, 1.0f, 1.0f);
        Color3f diffuseColour = new Color3f(1.0f, 1.0f, 0.0f);
        float shininess = 20.0f;
        app.setMaterial(new Material(ambientColour, emissiveColour, diffuseColour, specularColour, shininess));
        //Make the cubes
        Box leftCube = new Box(1.0f, 1.0f, 1.0f, app);
        ColorCube rightCube = new ColorCube();
        //Create the transformgroup used for the billboard
        TransformGroup billBoardGroup = new TransformGroup();
        //Set the access rights to the group
        billBoardGroup.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
        //Add the cube to the group
        billBoardGroup.addChild(rightCube);
        //Create and activate the billboard
        Billboard myBillboard = new Billboard(billBoardGroup, Billboard.ROTATE_ABOUT_AXIS,
                new Vector3f(0.0f, 1.0f, 0.0f));
        myBillboard.setSchedulingBounds(bounds);
        BranchGroup contentBranch = new BranchGroup();
        contentBranch.addChild(myBillboard);
        addLights(contentBranch);
        //Position the cubes
        TransformGroup bothGroup = new TransformGroup();
        Transform3D leftGroupXfm = new Transform3D();
        leftGroupXfm.set(new Vector3d(-1.5, 0.0, 0.0));
        TransformGroup leftGroup = new TransformGroup(leftGroupXfm);
        Transform3D rightGroupXfm = new Transform3D();
        rightGroupXfm.set(new Vector3d(1.5, 0.0, 0.0));
        TransformGroup rightGroup = new TransformGroup(rightGroupXfm);
        //Put it all together
        bothGroup.addChild(leftGroup);
        leftGroup.addChild(leftCube);
        bothGroup.addChild(rightGroup);
        rightGroup.addChild(billBoardGroup);
        contentBranch.addChild(bothGroup);
        return contentBranch;

    }

    /**
     * Use the action event of the exit button to end the application.
     */
    public void actionPerformed(ActionEvent e) {
        dispose();
        System.exit(0);
    }

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

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