Pure immediate mode example program. In pure immediate mode, the renderer must be stopped on the Canvas being rendered into. In our example, this is done immediately after the canvas is created. A separate thread is started up to do the immediate mode rendering.

 import java.applet.Applet;
import java.awt.BorderLayout;
import java.awt.GraphicsConfiguration;

import javax.media.j3d.Alpha;
import javax.media.j3d.Appearance;
import javax.media.j3d.Canvas3D;
import javax.media.j3d.Geometry;
import javax.media.j3d.GraphicsContext3D;
import javax.media.j3d.Transform3D;

import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.geometry.ColorCube;
import com.sun.j3d.utils.universe.SimpleUniverse;

/**
 * Pure immediate mode example program. In pure immediate mode, the renderer
 * must be stopped on the Canvas being rendered into. In our example, this is
 * done immediately after the canvas is created. A separate thread is started up
 * to do the immediate mode rendering.
 */
public class PureImmediate extends Applet implements Runnable {

  private Canvas3D canvas;

  private GraphicsContext3D gc = null;

  private Geometry cube = null;

  private Transform3D cmt = new Transform3D();

  // One rotation (2*PI radians) every 6 seconds
  private Alpha rotAlpha = new Alpha(-1, 6000);

  private SimpleUniverse u = null;

  //
  // Renders a single frame by clearing the canvas, drawing the
  // geometry, and swapping the draw and display buffer.
  //
  public void render() {
    if (gc == null) {
      // Set up Graphics context
      gc = canvas.getGraphicsContext3D();
      gc.setAppearance(new Appearance());

      // Set up geometry
      cube = new ColorCube(0.4).getGeometry();
    }

    // Compute angle of rotation based on alpha value
    double angle = rotAlpha.value() * 2.0 * Math.PI;
    cmt.rotY(angle);

    // Render the geometry for this frame
    gc.clear();
    gc.setModelTransform(cmt);
    gc.draw(cube);
    canvas.swap();
  }

  //
  // Run method for our immediate mode rendering thread.
  //
  public void run() {
    System.out.println("PureImmediate.run: starting main loop");
    while (true) {
      render();
      Thread.yield();
    }
  }

  public PureImmediate() {
  }

  //
  // init: create the canvas, stop the renderer,
  // create the universe, and start the drawing thread.
  //
  public void init() {
    setLayout(new BorderLayout());
    GraphicsConfiguration config = SimpleUniverse
        .getPreferredConfiguration();

    canvas = new Canvas3D(config);
    canvas.stopRenderer();
    add("Center", canvas);

    // Create the universe and viewing branch
    u = new SimpleUniverse(canvas);

    // This will move the ViewPlatform back a bit so the
    // objects in the scene can be viewed.
    u.getViewingPlatform().setNominalViewingTransform();

    // Start a new thread that will continuously render
    new Thread(this).start();
  }

  public void destroy() {
    u.cleanup();
  }

  //
  // The following allows PureImmediate to be run as an application
  // as well as an applet
  //
  public static void main(String[] args) {
    new MainFrame(new PureImmediate(), 256, 256);
  }
}