SimpleSpotLights.java Source code

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Here is the source code for SimpleSpotLights.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.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.media.j3d.AmbientLight;
import javax.media.j3d.Appearance;
import javax.media.j3d.BoundingSphere;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.Locale;
import javax.media.j3d.Material;
import javax.media.j3d.PhysicalBody;
import javax.media.j3d.PhysicalEnvironment;
import javax.media.j3d.SpotLight;
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.AxisAngle4d;
import javax.vecmath.Color3f;
import javax.vecmath.Point3d;
import javax.vecmath.Point3f;
import javax.vecmath.Vector3f;

import com.sun.j3d.utils.geometry.Sphere;

/**
 * This builds a red sphere using the Sphere utility class and adds lights so
 * that you can see it shape. It creates a material for the sphere, creates an
 * ambient light and a two spot lights of different colours.
 * 
 * @author I.J.Palmer
 * @version 1.0
 */
public class SimpleSpotLights extends Frame implements ActionListener {
    protected Canvas3D myCanvas3D = new Canvas3D(null);

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

    /**
     * This function builds the view branch of the scene graph. It creates a
     * branch group and then creates the necessary view elements to give a
     * useful view of our content.
     * 
     * @param c
     *            Canvas3D that will display the view
     * @return BranchGroup that is the root of the view elements
     */
    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);
        ViewPlatform myViewPlatform = new ViewPlatform();
        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);
        return viewBranch;
    }

    /**
     * This creates some lights and adds them to the BranchGroup.
     * 
     * @param b
     *            BranchGroup that the lights are added to.
     */
    protected void addLights(BranchGroup b) {
        // Create a bounds for the lights
        BoundingSphere bounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);
        //Set up the ambient light
        Color3f ambientColour = new Color3f(0.2f, 0.2f, 0.2f);
        AmbientLight ambientLight = new AmbientLight(ambientColour);
        ambientLight.setInfluencingBounds(bounds);
        Color3f blueColour = new Color3f(0.0f, 0.0f, 1.0f);
        Point3f bluePosition = new Point3f(1.8f, 1.8f, 1.8f);
        Point3f blueAtten = new Point3f(1.0f, 0.0f, 0.0f);
        Vector3f blueDir = new Vector3f(-1.0f, -1.0f, -1.0f);
        SpotLight blueLight = new SpotLight(blueColour, bluePosition, blueAtten, blueDir, (float) (Math.PI / 2.0),
                0.0f);
        blueLight.setInfluencingBounds(bounds);
        Color3f greenColour = new Color3f(0.0f, 1.0f, 0.0f);
        Point3f greenPosition = new Point3f(0.0f, 0.0f, 3.0f);
        Point3f greenAtten = new Point3f(1.0f, 0.0f, 0.0f);
        Vector3f greenDir = new Vector3f(0.0f, 0.0f, -1.0f);
        SpotLight greenLight = new SpotLight(greenColour, greenPosition, greenAtten, greenDir,
                (float) (Math.PI / 2.0), 0.0f);
        greenLight.setInfluencingBounds(bounds);
        //Add the lights to the BranchGroup
        b.addChild(ambientLight);
        b.addChild(greenLight);
        b.addChild(blueLight);
    }

    /**
     * This build the content branch of our scene graph. It creates a transform
     * group so that the shape is slightly tilted to reveal its 3D shape.
     * 
     * @param shape
     *            Node that represents the geometry for the content
     * @return BranchGroup that is the root of the content branch
     */
    protected BranchGroup buildContentBranch() {
        BranchGroup contentBranch = new BranchGroup();
        Transform3D rotateCube = new Transform3D();
        rotateCube.set(new AxisAngle4d(1.0, 1.0, 0.0, Math.PI / 4.0));
        TransformGroup rotationGroup = new TransformGroup(rotateCube);
        contentBranch.addChild(rotationGroup);
        //Create a new appearance
        Appearance app = new Appearance();
        //Create the colours for the material
        Color3f ambientColour = new Color3f(1.0f, 1.0f, 1.0f);
        Color3f diffuseColour = new Color3f(1.0f, 1.0f, 1.0f);
        Color3f specularColour = new Color3f(1.0f, 1.0f, 1.0f);
        Color3f emissiveColour = new Color3f(0.0f, 0.0f, 0.0f);
        //Define the shininess
        float shininess = 20.0f;
        //Set the material of the appearance
        app.setMaterial(new Material(ambientColour, emissiveColour, diffuseColour, specularColour, shininess));
        //Create and add a new sphere using the appearance
        rotationGroup.addChild(new Sphere(2.0f, Sphere.GENERATE_NORMALS, 120, app));
        //Use the addLights function to add the lights to the branch
        addLights(contentBranch);
        //Return the root of the content branch
        return contentBranch;
    }

    /**
     * Handles the exit button action to quit the program.
     */
    public void actionPerformed(ActionEvent e) {
        dispose();
        System.exit(0);
    }

    /**
     * This creates a default universe and locale, creates a window and uses the
     * functions defined in this class to build the view and content branches of
     * the scene graph.
     */
    public SimpleSpotLights() {
        VirtualUniverse myUniverse = new VirtualUniverse();
        Locale myLocale = new Locale(myUniverse);
        myLocale.addBranchGraph(buildViewBranch(myCanvas3D));
        myLocale.addBranchGraph(buildContentBranch());
        setTitle("SimpleDirLight");
        setSize(400, 400);
        setLayout(new BorderLayout());
        add("Center", myCanvas3D);
        add("South", myButton);
        myButton.addActionListener(this);
        setVisible(true);
    }

    public static void main(String[] args) {
        SimpleSpotLights spl = new SimpleSpotLights();
    }
}