SimpleWorld.java Source code

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Here is the source code for SimpleWorld.java

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/*
Essential Java 3D Fast
    
Ian Palmer
    
Publisher: Springer-Verlag
    
ISBN: 1-85233-394-4
    
*/
//Import the Java3D classes

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.Appearance;
import javax.media.j3d.BranchGroup;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.Locale;
import javax.media.j3d.Node;
import javax.media.j3d.PhysicalBody;
import javax.media.j3d.PhysicalEnvironment;
import javax.media.j3d.QuadArray;
import javax.media.j3d.Shape3D;
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.Vector3f;

/**
 * This is our first simple program that creates a cube. We have no lighting
 * defined so the object appears a bright white colour. The cube is tilted
 * slightly so that we can see its shape by creating a transform group.
 * 
 * @author I.J.Palmer
 * @version 1.0
 */
public class SimpleWorld extends Frame implements ActionListener {
    /** The canvas 3D used to display the scene. */
    protected Canvas3D myCanvas3D = new Canvas3D(null);

    /** The AWT button used to exit the application. */
    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) {
        //This is the root of our view branch
        BranchGroup viewBranch = new BranchGroup();

        //The transform that will move our view
        //back 5 units along the z-axis
        Transform3D viewXfm = new Transform3D();
        viewXfm.set(new Vector3f(0.0f, 0.0f, 5.0f));

        //The transform group that will be the parent
        //of our view platform elements
        TransformGroup viewXfmGroup = new TransformGroup(viewXfm);
        ViewPlatform myViewPlatform = new ViewPlatform();

        //Next the physical elements are created
        PhysicalBody myBody = new PhysicalBody();
        PhysicalEnvironment myEnvironment = new PhysicalEnvironment();

        //Then we put it all together
        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 builds the content branch of our scene graph. It uses the buildCube
     * function to create the actual shape, adding to to the 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(Node shape) {
        //Create the branch group that will be the root of the content branch
        BranchGroup contentBranch = new BranchGroup();

        //Create the transform that will cause the shape to appear tilted
        Transform3D rotateCube = new Transform3D();
        rotateCube.set(new AxisAngle4d(1.0, 1.0, 0.0, Math.PI / 4.0));
        TransformGroup rotationGroup = new TransformGroup(rotateCube);

        //Put the branch together
        contentBranch.addChild(rotationGroup);
        rotationGroup.addChild(shape);

        return contentBranch;
    }

    /**
     * This constructs a cube as an array of quadrilateral polygons. There are
     * six faces, each with four vertices (obviously!). The cube extends 1 unit
     * along each axis in the positive and negavtive directions and is centred
     * on the origin.
     * 
     * @return Shape3D that is the cube
     */
    protected Shape3D buildCube() {
        //Create the array of numbers that will form the
        //vertex information.
        float[] cubeFaces = { 1.0f, -1.0f, 1.0f, 1.0f, 1.0f, 1.0f, -1.0f, 1.0f, 1.0f, -1.0f, -1.0f, 1.0f, -1.0f,
                -1.0f, -1.0f, -1.0f, 1.0f, -1.0f, 1.0f, 1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f,
                1.0f, -1.0f, 1.0f, 1.0f, 1.0f, 1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, -1.0f, 1.0f, 1.0f, -1.0f,
                1.0f, -1.0f, -1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, -1.0f, -1.0f, 1.0f, -1.0f, -1.0f,
                1.0f, 1.0f, -1.0f, -1.0f, 1.0f, -1.0f, -1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, -1.0f, 1.0f };

        //Create the array of quadrilaterals from the vertices
        QuadArray cubeData = new QuadArray(24, QuadArray.COORDINATES);
        cubeData.setCoordinates(0, cubeFaces);

        //Create a default appearance
        Appearance app = new Appearance();

        //Create and return the cube
        return new Shape3D(cubeData, app);
    }

    /**
     * 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 SimpleWorld() {
        //Create a default universe and locale
        VirtualUniverse myUniverse = new VirtualUniverse();
        Locale myLocale = new Locale(myUniverse);

        //Use the functions to build the scene graph
        myLocale.addBranchGraph(buildViewBranch(myCanvas3D));
        myLocale.addBranchGraph(buildContentBranch(buildCube()));

        //Do some AWT stuff to set up the window
        setTitle("SimpleWorld");
        setSize(400, 400);
        setLayout(new BorderLayout());
        add("Center", myCanvas3D);
        myButton.addActionListener(this);
        add("South", myButton);
        setVisible(true);
    }

    /**
     * Just create the class and run!
     */
    public static void main(String[] args) {
        SimpleWorld sw = new SimpleWorld();
    }
}