code: function (layer) {
              return function (attributes, record) {
                  // Add the label for a name record in the database to a separate layer.
                  if (!!layer) {
                      addLabelForName(attributes, record, layer);
                  }
  
                  if (record.isPointType()) {
                      // Modify placemark attributes in a data dependent manner as appropriate.
  
                      var currentPlacemarkAttributes = new WorldWind.PlacemarkAttributes(placemarkAttributes);
  
                      if (attributes.values.hasOwnProperty('pop_max')) {
                          var population = attributes.values.pop_max;
                          currentPlacemarkAttributes.imageScale = 0.01 * Math.log(population);
                      }
  
                      return {attributes: currentPlacemarkAttributes};
                  }
                  else {
                      // This should never be reached.
                      alert("Invalid record type was encountered!");
                      return null;
                  }
              }
          }
docs: For this example, cities are provided in a shapefile that just has points, and a database that has names (among other attributes).