docs: function(boundsOnly) {
          var onScreen = false;
          if(this.layer && this.layer.map) {
              var screenBounds = this.layer.map.getExtent();
              if(boundsOnly) {
                  var featureBounds = this.geometry.getBounds();
                  onScreen = screenBounds.intersectsBounds(featureBounds);
              } else {
                  var screenPoly = screenBounds.toGeometry();
                  onScreen = screenPoly.intersects(this.geometry);
              }
          }    
          return onScreen;
      }