anchor.diff:              newNodeData.orientationSink.add(orientation);
   
               itemRenderer.orientation$sink.add(orientation);
  +
  +            newNodeData.node.recursiveWidth$sink.add(.0);
  +            newNodeData.node.recursiveHeight$sink.add(.0);
             });
   
             itemRenderer.renderingRequired$.listen((_) => renderer.materializeStage$sink.add(true));
  
positive.code:     renderer.orientation$sink.add(orientation);
      topLevelNodeData.orientationSink.add(orientation);
      _orientation$ctrl.add(orientation);
    }
  
    Future<Iterable<RenderState<T>>> _digest(Digestable digestable) {
  
negative.code:             newNodeData.orientationSink.add(orientation);
  
              itemRenderer.orientation$sink.add(orientation);
  
              newNodeData.node.recursiveWidth$sink.add(.0);
              newNodeData.node.recursiveHeight$sink.add(.0);
            });
  
            itemRenderer.renderingRequired$.listen((_) => renderer.materializeStage$sink.add(true));
  