public SpinningTopSpaceView(SpinningTop rigidBody) {
   this.rigidBody = rigidBody;
   frame.setSize(600, 600);
   // panel.setDisplayMode(VisualizationHints.DISPLAY_NO_PERSPECTIVE);
   double d = 4;
   frame.setPreferredMinMax(-d, d, -d, d, -d, d);
   frame.setDecorationType(
       org.opensourcephysics.display3d.core.VisualizationHints.DECORATION_AXES);
   orientation.getStyle().setFillColor(java.awt.Color.RED);
   orientationTrace.getStyle().setLineColor(java.awt.Color.BLACK);
   base.setSizeXYZ(2, 2, 0.15);
   base.getStyle().setResolution(new Resolution(4, 12, 1));
   base.getStyle().setFillColor(java.awt.Color.RED);
   base.setZ(-3);
   post.setSizeXYZ(0.2, 0.2, 3);
   post.getStyle().setResolution(new Resolution(2, 10, 15));
   post.setZ(-1.5); // shift by half the length
   post.getStyle().setFillColor(java.awt.Color.RED);
   shaft.setSizeXYZ(0.2, 0.2, 3);
   shaft.setXYZ(0, 0, 1.5);
   shaft.getStyle().setResolution(new Resolution(1, 10, 15));
   disk.setSizeXYZ(1.75, 1.75, 0.25);
   disk.setXYZ(0, 0, 2.0);
   disk.getStyle().setResolution(new Resolution(4, 12, 1));
   topGroup.addElement(shaft);
   topGroup.addElement(disk);
   topGroup.setTransformation(rigidBody.getTransformation());
   frame.addElement(base);
   frame.addElement(post);
   frame.addElement(orientation);
   frame.addElement(orientationTrace);
   frame.addElement(topGroup);
 }
 void initialize() {
   double dx = 1 / Math.sqrt(rigidBody.I1); // dimension of ellipsoid is inverse to inertia
   double dy = 1 / Math.sqrt(rigidBody.I2);
   double dz = 1 / Math.sqrt(rigidBody.I3);
   double scale = Math.max(Math.max(4 * dx, 4 * dy), 4 * dz); // bounding dimension
   frame.setPreferredMinMax(-scale, scale, -scale, scale, -scale, scale);
   orientationTrace.clear();
   update();
 }