URGENT: Custom Behavior Problem

Question

I'm writing an application which must plot a 3D curve. It has 3 panels, each of which has a 2D projection of the curve (xy, xz, yz). Moving the points on the panels will change the properties of the underlying 3D curve.
When I start the application, The 3D curve is shown correctly, but when I move the points, the 3D curve disappears.
The problem is not the canvas3d not being redrawn, because resizing the window doesn't bring the curve back. Any idea why the curve isn't redrawn?
The code for the curve is as follows:
import javax.media.j3d.*;
import javax.vecmath.*;
import java.lang.Math.*;
public class CubicCurve3D extends Shape3D{
     public CubicCurve3D(Point3d p1, Point3d p2, Point3d p3, Point3d p4){
          this.setGeometry(createGeometry(p1,p2,p3,p4));
     public Geometry createGeometry(Point3d p1, Point3d p2, Point3d p3, Point3d p4){
          // setup the LineArray to represent the curve
          LineArray curveLine = new LineArray(148, GeometryArray.COORDINATES);
          // Add vertices to the array
          setupLineArray(p1,p2,p3,p4,curveLine);
          return curveLine;
     // This method adds the vertices into the array
     public void setupLineArray(Point3d p1, Point3d p2, Point3d p3, Point3d p4, LineArray curve){
          final Point3d p = new Point3d();;
          double nx = 0;
          double ny = 0;
          double nz = 0;
          double u = 0.0;
          int lIndex = 0;
          for(int i=0;i<75;i++){
               u = ((double)i/100)/0.75;
               // Equations to work out point
               nx = ((p1.x)*Math.pow((1-u),3.0)) + ((p2.x)*(3*u)*Math.pow((1-u),2.0)) + ((p3.x)*(3*u*u)*(1-u)) + ((p4.x)*Math.pow(u,3.0));
               ny = ((p1.y)*Math.pow((1-u),3.0)) + ((p2.y)*(3*u)*Math.pow((1-u),2.0)) + ((p3.y)*(3*u*u)*(1-u)) + ((p4.y)*Math.pow(u,3.0));
               nz = ((p1.z)*Math.pow((1-u),3.0)) + ((p2.z)*(3*u)*Math.pow((1-u),2.0)) + ((p3.z)*(3*u*u)*(1-u)) + ((p4.z)*Math.pow(u,3.0));
               p.set(nx,ny,nz);
               // Put point into LineArray
               curve.setCoordinate(lIndex,p);
               if((i > 0) && (i < 74)){
                    lIndex++;
                    curve.setCoordinate(lIndex,p);
               lIndex++;
     public void updateGeometry(Point3d p1, Point3d p2, Point3d p3, Point3d p4){
          this.setGeometry(createGeometry(p1,p2,p3,p4));
}The behavior, called UpdateBehavior, is:
import javax.media.j3d.*;
import javax.vecmath.*;
import java.util.Enumeration;
public class UpdateBehavior extends Behavior
     // The set of points to be updated
     private Point3d[] points;
     private CubicCurve3D cc;
     public UpdateBehavior(CubicCurve3D c)
          cc = c;
          postId(1);
     public void initialize()
          this.wakeupOn(new WakeupOnBehaviorPost(this, 1));
     public void processStimulus(Enumeration e)
          cc.updateGeometry(points[0],points[1],points[2],points[3]);
          this.wakeupOn(new WakeupOnBehaviorPost(this, 1));
     public void setNewPoints(Point3d[] p)
          points = p;
          this.postId(1);
}And the createSceneGraph() method from the Graph3D class is:
     public BranchGroup createSceneGraph() {
          // Create the root of the branch group
          BranchGroup objRoot = new BranchGroup();
          // rotate object has composite transformation matrix
          Transform3D rotate = new Transform3D();
          Transform3D tempRotate = new Transform3D();
          rotate.rotX(Math.PI/20.0d);
          tempRotate.rotY(Math.PI/6.0d);
          rotate.mul(tempRotate);
          TransformGroup objRotate = new TransformGroup(rotate);
          cc = new CubicCurve3D(points[0],points[1],points[2],points[3]);
          cc.setCapability(Shape3D.ALLOW_GEOMETRY_WRITE);
          cc.setCapability(Shape3D.ALLOW_GEOMETRY_READ);
          Line3D ax1 = new Line3D(new Point3d(0,0,0), new Point3d(0.75,0,0));
          Line3D ax2 = new Line3D(new Point3d(0,0,0), new Point3d(0,0.75,0));
          Line3D ax3 = new Line3D(new Point3d(0,0,0), new Point3d(0,0,0.75));
          objRotate.addChild(ax1);
          objRotate.addChild(ax2);
          objRotate.addChild(ax3);
          objRotate.addChild(cc);
          uBehavior = new UpdateBehavior(cc);
          uBehavior.setSchedulingBounds(new BoundingSphere());
          objRoot.addChild(objRotate);
          objRoot.addChild(uBehavior);
          return objRoot;
     }Graph3D also has a method updatePoints():
     public void updatePoints(Point3d[] p)
          points = p;
          uBehavior.setNewPoints(points);
          System.out.println(cc.getP1() + "," + cc.getP2() + "," + cc.getP3() + "," + cc.getP4());

Answer 1

Have you checked if the processStimulus method will ever be executed (e.g. print something or use a debugger and set a breakpoint). If it is not executed maybe the radius of the BoundingSphere of the Behavior is to small ?
I don't know what the initial values of the points and the values of the points you are supplying after change are. So check the coordinates of the new created points ad the calculated curve points.
Is the curve moving out of the viewing frustrum (behind the front or back clipping planes) ?
Add some Appearance object with a color other than the default.