/*
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();
}
}
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