anchor.diff:      # https://developers.google.com/maps/documentation/javascript/tutorial#zoom-levels
       zoom = 10
     end
  +end
  +if !defined?(marker_cluster)
  +  marker_cluster = false
   end
   Rails.logger.debug{"map/display latitude: #{defined?(latitude)}, #{latitude.inspect}"}
   if !defined?(latitude) || latitude.nil?
  
positive.code:       return marker;
      });
      
      new MarkerClusterer(
        map,
        markers,
        {
          imagePath: "https://developers.google.com/maps/documentation/javascript/examples/markerclusterer/m"
        }
      );
    }
  </script>
  
negative.code:         position: location.position,
          label: location.label,
          title: location.tooltip,
          <% if !marker_cluster %>
          map: map,
          <% end %>
        });
        if (location.popupHtml) {
          var infoWindow = new google.maps.InfoWindow({
  