docs: function(renderer) {
          var layer = this.map.getLayer(renderer.container.id);
          if(layer instanceof OpenLayers.Layer.Vector.RootContainer) {
              layer = this.map.getLayer(this.container.id);
          }
          layer && layer.renderer.clear();
          OpenLayers.Renderer.Elements.prototype.moveRoot.apply(this, arguments);
          layer && layer.redraw();
      }