s.link.fromNode.ensureBounds();
        this.link.toNode.ensureBounds();
        this.link.updateRoute();
      }
      super.commit();
      if (this.data && routed) {
        this.data.points = this.link.points.copy();
        this.link = null;
      }
    }
  }

  // end of VirtualizedTree[Layout/Network] classes

  // This function is only used in this sample to demonstrate the effects of the virtualization.
  // In a real application you would delete this function and all calls to it.
  function update