anchor.diff:        base + "/" + endpoint + "/" + endpointID + "/{z}/{x}/{y}.png", options );
     });
     return this.addLayerAndControl( { tiles: tileURLs }, options );
  -};
  -
  -google.maps.Map.prototype.addLayerByEndpoint = function( endpoint, endpointID, options ) {
  -  // prevent the tilt feature, which cannot overlay tiles at higher zooms
  -  this.setTilt(0);
  -  var options = options || { },
  -      layerTileURL = <%= CONFIG.tile_servers.windshaft.inspect %> +
  -        "/" + endpoint + "/" + endpointID + "/{z}/{x}/{y}.png";
  -  layerTileURL = appendValidParamsToURL( layerTileURL, options );
  -  return this.addLayerAndControl( { tiles: [ layerTileURL ] }, options );
   };
   
   // Convenience method that likely isn't called outside this file.
  
positive.code:   var options = options || {},
        interactivity = options.interactivity;
    if( options.interactivity ) {
      // windshaft needs the interactivity param to know what data to render
      options.grids = _.map( tileURLs, function( l ) {
        return google.maps.Map.prototype.interactivityURL( l, options.interactivity );
      })
    }
    // finish preparing the tile options hash
  
negative.code:   }
    // add a utfgrid data layer and custom JS events to catch interactivity
    if( options.interactivity ) {
      this.addTileInteractivity( tilejson, layerID, options );
    }
    // return the layer and index of this layer in the current stack
    return { layer: layer, layerID: layerID };
  }
  
  google.maps.Map.prototype.utfgridURL = function( tileURL ) {
    url = tileURL.replace( /\.png/, ".grid.json" );
    url += ( url.indexOf("?") < 0 ) ? "?" : "&";
    return url;
  };
  
  google.maps.Map.prototype.addTileInteractivity = function( tilejson, layerID, options ) {
    var map = this;
    var interactionOn = false;
    var waxInteraction = wax.g.interaction( );
    var oldFeature = waxInteraction.screen_feature;
    waxInteraction.screen_feature = function( pos, callback ) {
      // making sure the colored heatmap doesn't have offset interactions
      if( options.maxzoom && map.getZoom( ) <= options.maxzoom ) {
        return oldFeature( pos, callback );
      }
      oldFeature( { x: pos.x, y: pos.y + 13 }, function( f ) {
        if( f && f.mappable === "true" && !f.private_location ) { return callback( f ); }
        oldFeature( pos, function( f ) {
  