code: public void showControllerModel(boolean flag)
      {
          boolean show = flag && isEnabled();
          mShowControllerModel = flag;
          if (mControllerModel != null)
          {
              mControllerModel.setEnable(show);
              mControllerGroup.setEnable(show);
          }
          else if (show)
          {
              createControllerModel();
          }
      }
docs: Show or hide the controller model and picking ray.
  <p>
  The scene objects remain in the scene but they are not rendered.
  
  @param flag true to show the model and ray, false to hide it.