Displaying a basic sphere

Question

hi guys..i am new to java3d need help to solve a rudimentary problem - displaying a sphere on the screen...
following is the code i have so far:
import com.sun.j3d.utils.applet.MainFrame;
import java.awt.GraphicsConfiguration;
import com.sun.j3d.utils.geometry.*;
import com.sun.j3d.utils.universe.*;
import java.awt.BorderLayout;
import java.awt.event.*;
import javax.media.j3d.*;
import javax.vecmath.*;
import java.applet.*;
import java.awt.Frame;
public class primary_struct extends Applet {
     primary_struct() {
          setLayout(new BorderLayout());
          GraphicsConfiguration config = SimpleUniverse.getPreferredConfiguration();
          Canvas3D canvas3D = new Canvas3D(config);
          add("Center", canvas3D);
          BranchGroup scene = new BranchGroup();
          addSphere(scene);
          scene.compile();
          SimpleUniverse simpleU = new SimpleUniverse(canvas3D);
          simpleU.getViewingPlatform().setNominalViewingTransform();
          simpleU.addBranchGraph(scene);
     public void addSphere(BranchGroup objRoot) {
          objRoot.addChild(new Sphere(0.1f,1,200));
     public static void main(String[] args) {
          new MainFrame(new primary_struct(),256,256);
}Results:
Compilation is successful.
This just prints out a 256x256 black screen...I don't see a sphere.
Seeing this, I have two questions:
- where in this code does it show that the screen is set to a black background color..
- how do i print a visible sphere??
Thanks in advance.

Answer 1

Black is the default background. Here is code to change the background.
     //Change Background to white
Color3f white = new Color3f(1.0f, 1.0f, 1.0f); // white color
     BoundingSphere bounds = new BoundingSphere(new Point3d(), 100.0);
     Background backg = new Background(white);
     backg.setApplicationBounds(bounds);
     objRoot.addChild(backg);
Just change the numbers in the Color3f(...) to get different colors.
Try that. As far as your sphere not showing, there are plenty of tutorials out that can help you with that.