text: // ==ClosureCompiler==
  // @compilation_level ADVANCED_OPTIMIZATIONS
  // @externs_url http://closure-compiler.googlecode.com/svn/trunk/contrib/externs/maps/google_maps_api_v3_3.js
  // ==/ClosureCompiler==
  
  /**
   * @name MarkerClusterer for Google Maps v3
   * @version version 1.0
   * @author Luke Mahe
   * @fileoverview
   * The library creates and manages per-zoom-level clusters for large amounts of
   * markers.
   * <br/>
   * This is a v3 implementation of the
   * <a href="http://gmaps-utility-library-dev.googlecode.com/svn/tags/markerclusterer/"
   * >v2 MarkerClusterer</a>.
   */
  
  /**
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  
  /**
   * A Marker Clusterer that clusters markers.
   *
   * @param {google.maps.Map} map The Google map to attach to.
   * @param {Array.<google.maps.Marker>=} opt_markers Optional markers to add to
   *   the cluster.
   * @param {Object=} opt_options support the following options:
   *     'gridSize': (number) The grid size of a cluster in pixels.
   *     'maxZoom': (number) The maximum zoom level that a marker can be part of a
   *                cluster.
   *     'zoomOnClick': (boolean) Whether the default behaviour of clicking on a
   *                    cluster is to zoom into it.
   *     'averageCenter': (boolean) Wether the center of each cluster should be
   *                      the average of all markers in the cluster.
   *     'minimumClusterSize': (number) The minimum number of markers to be in a
   *                           cluster before the markers are hidden and a count
   *                           is shown.
   *     'styles': (object) An object that has style properties:
   *       'url': (string) The image url.
   *       'height': (number) The image height.
   *       'width': (number) The image width.
   *       'anchor': (Array) The anchor position of the label text.
   *       'textColor': (string) The text color.
   *       'textSize': (number) The text size.
   *       'backgroundPosition': (string) The position of the backgound x, y.
   *       'iconAnchor': (Array) The anchor position of the icon x, y.
   * @constructor
   * @extends google.maps.OverlayView
   */
  function MarkerClusterer(map, opt_markers, opt_options) {
    // MarkerClusterer implements google.maps.OverlayView interface. We use the
    // extend function to extend MarkerClusterer with google.maps.OverlayView
    // because it might not always be available when the code is defined so we
    // look for it at the last possible moment. If it doesn't exist now then
    // there is no point going ahead :)
    this.extend(MarkerClusterer, google.maps.OverlayView);
    this.map_ = map;
  
    /**
     * @type {Array.<google.maps.Marker>}
     * @private
     */
    this.markers_ = [];
  
    /**
     *  @type {Array.<Cluster>}
     */
    this.clusters_ = [];
  
    this.sizes = [53, 56, 66, 78, 90];
  
    /**
     * @private
     */
    this.styles_ = [];
  
    /**
     * @type {boolean}
     * @private
     */
    this.ready_ = false;
  
    var options = opt_options || {};
  
    /**
     * @type {number}
     * @private
     */
    this.gridSize_ = options['gridSize'] || 60;
  
    /**
     * @private
     */
    this.minClusterSize_ = options['minimumClusterSize'] || 2;
  
  
    /**
     * @type {?number}
     * @private
     */
    this.maxZoom_ = options['maxZoom'] || null;
  
    this.styles_ = options['styles'] || [];
  
    /**
     * @type {string}
     * @private
     */
    this.imagePath_ = options['imagePath'] ||
        this.MARKER_CLUSTER_IMAGE_PATH_;
  
    /**
     * @type {string}
     * @private
     */
    this.imageExtension_ = options['imageExtension'] ||
        this.MARKER_CLUSTER_IMAGE_EXTENSION_;
  
    /**
     * @type {boolean}
     * @private
     */
    this.zoomOnClick_ = true;
  
    if (options['zoomOnClick'] != undefined) {
      this.zoomOnClick_ = options['zoomOnClick'];
    }
  
    /**
     * @type {boolean}
     * @private
     */
    this.averageCenter_ = false;
  
    if (options['averageCenter'] != undefined) {
      this.averageCenter_ = options['averageCenter'];
    }
  
    this.setupStyles_();
  
    this.setMap(map);
  
    /**
     * @type {number}
     * @private
     */
    this.prevZoom_ = this.map_.getZoom();
  
    // Add the map event listeners
    var that = this;
    google.maps.event.addListener(this.map_, 'zoom_changed', function() {
      var zoom = that.map_.getZoom();
  
      if (that.prevZoom_ != zoom) {
        that.prevZoom_ = zoom;
        that.resetViewport();
      }
    });
  
    google.maps.event.addListener(this.map_, 'idle', function() {
      that.redraw();
    });
  
    // Finally, add the markers
    if (opt_markers && opt_markers.length) {
      this.addMarkers(opt_markers, false);
    }
  }
  
  
  /**
   * The marker cluster image path.
   *
   * @type {string}
   * @private
   */
  MarkerClusterer.prototype.MARKER_CLUSTER_IMAGE_PATH_ = '../images/m';
  
  
  /**
   * The marker cluster image path.
   *
   * @type {string}
   * @private
   */
  MarkerClusterer.prototype.MARKER_CLUSTER_IMAGE_EXTENSION_ = 'png';
  
  
  /**
   * Extends a objects prototype by anothers.
   *
   * @param {Object} obj1 The object to be extended.
   * @param {Object} obj2 The object to extend with.
   * @return {Object} The new extended object.
   * @ignore
   */
  MarkerClusterer.prototype.extend = function(obj1, obj2) {
    return (function(object) {
      for (var property in object.prototype) {
        this.prototype[property] = object.prototype[property];
      }
      return this;
    }).apply(obj1, [obj2]);
  };
  
  
  /**
   * Implementaion of the interface method.
   * @ignore
   */
  MarkerClusterer.prototype.onAdd = function() {
    this.setReady_(true);
  };
  
  /**
   * Implementaion of the interface method.
   * @ignore
   */
  MarkerClusterer.prototype.draw = function() {};
  
  /**
   * Sets up the styles object.
   *
   * @private
   */
  MarkerClusterer.prototype.setupStyles_ = function() {
    if (this.styles_.length) {
      return;
    }
  
    for (var i = 0, size; size = this.sizes[i]; i++) {
      this.styles_.push({
        url: this.imagePath_ + (i + 1) + '.' + this.imageExtension_,
        height: size,
        width: size
      });
    }
  };
  
  /**
   *  Fit the map to the bounds of the markers in the clusterer.
   */
  MarkerClusterer.prototype.fitMapToMarkers = function() {
    var markers = this.getMarkers();
    var bounds = new google.maps.LatLngBounds();
    for (var i = 0, marker; marker = markers[i]; i++) {
      bounds.extend(marker.getPosition());
    }
  
    this.map_.fitBounds(bounds);
  };
  
  
  /**
   *  Sets the styles.
   *
   *  @param {Object} styles The style to set.
   */
  MarkerClusterer.prototype.setStyles = function(styles) {
    this.styles_ = styles;
  };
  
  
  /**
   *  Gets the styles.
   *
   *  @return {Object} The styles object.
   */
  MarkerClusterer.prototype.getStyles = function() {
    return this.styles_;
  };
  
  
  /**
   * Whether zoom on click is set.
   *
   * @return {boolean} True if zoomOnClick_ is set.
   */
  MarkerClusterer.prototype.isZoomOnClick = function() {
    return this.zoomOnClick_;
  };
  
  /**
   * Whether average center is set.
   *
   * @return {boolean} True if averageCenter_ is set.
   */
  MarkerClusterer.prototype.isAverageCenter = function() {
    return this.averageCenter_;
  };
  
  
  /**
   *  Returns the array of markers in the clusterer.
   *
   *  @return {Array.<google.maps.Marker>} The markers.
   */
  MarkerClusterer.prototype.getMarkers = function() {
    return this.markers_;
  };
  
  
  /**
   *  Returns the number of markers in the clusterer
   *
   *  @return {Number} The number of markers.
   */
  MarkerClusterer.prototype.getTotalMarkers = function() {
    return this.markers_.length;
  };
  
  
  /**
   *  Sets the max zoom for the clusterer.
   *
   *  @param {number} maxZoom The max zoom level.
   */
  MarkerClusterer.prototype.setMaxZoom = function(maxZoom) {
    this.maxZoom_ = maxZoom;
  };
  
  
  /**
   *  Gets the max zoom for the clusterer.
   *
   *  @return {number} The max zoom level.
   */
  MarkerClusterer.prototype.getMaxZoom = function() {
    return this.maxZoom_;
  };
  
  
  /**
   *  The function for calculating the cluster icon image.
   *
   *  @param {Array.<google.maps.Marker>} markers The markers in the clusterer.
   *  @param {number} numStyles The number of styles available.
   *  @return {Object} A object properties: 'text' (string) and 'index' (number).
   *  @private
   */
  MarkerClusterer.prototype.calculator_ = function(markers, numStyles) {
    var index = 0;
    var count = markers.length;
    var dv = count;
    while (dv !== 0) {
      dv = parseInt(dv / 10, 10);
      index++;
    }
  
    index = Math.min(index, numStyles);
    return {
      text: count,
      index: index
    };
  };
  
  
  /**
   * Set the calculator function.
   *
   * @param {function(Array, number)} calculator The function to set as the
   *     calculator. The function should return a object properties:
   *     'text' (string) and 'index' (number).
   *
   */
  MarkerClusterer.prototype.setCalculator = function(calculator) {
    this.calculator_ = calculator;
  };
  
  
  /**
   * Get the calculator function.
   *
   * @return {function(Array, number)} the calculator function.
   */
  MarkerClusterer.prototype.getCalculator = function() {
    return this.calculator_;
  };
  
  
  /**
   * Add an array of markers to the clusterer.
   *
   * @param {Array.<google.maps.Marker>} markers The markers to add.
   * @param {boolean=} opt_nodraw Whether to redraw the clusters.
   */
  MarkerClusterer.prototype.addMarkers = function(markers, opt_nodraw) {
    for (var i = 0, marker; marker = markers[i]; i++) {
      this.pushMarkerTo_(marker);
    }
    if (!opt_nodraw) {
      this.redraw();
    }
  };
  
  
  /**
   * Pushes a marker to the clusterer.
   *
   * @param {google.maps.Marker} marker The marker to add.
   * @private
   */
  MarkerClusterer.prototype.pushMarkerTo_ = function(marker) {
    marker.isAdded = false;
    if (marker['draggable']) {
      // If the marker is draggable add a listener so we update the clusters on
      // the drag end.
      var that = this;
      google.maps.event.addListener(marker, 'dragend', function() {
        marker.isAdded = false;
        that.repaint();
      });
    }
    this.markers_.push(marker);
  };
  
  
  /**
   * Adds a marker to the clusterer and redraws if needed.
   *
   * @param {google.maps.Marker} marker The marker to add.
   * @param {boolean=} opt_nodraw Whether to redraw the clusters.
   */
  MarkerClusterer.prototype.addMarker = function(marker, opt_nodraw) {
    this.pushMarkerTo_(marker);
    if (!opt_nodraw) {
      this.redraw();
    }
  };
  
  
  /**
   * Removes a marker and returns true if removed, false if not
   *
   * @param {google.maps.Marker} marker The marker to remove
   * @return {boolean} Whether the marker was removed or not
   * @private
   */
  MarkerClusterer.prototype.removeMarker_ = function(marker) {
    var index = -1;
    if (this.markers_.indexOf) {
      index = this.markers_.indexOf(marker);
    } else {
      for (var i = 0, m; m = this.markers_[i]; i++) {
        if (m == marker) {
          index = i;
          break;
        }
      }
    }
  
    if (index == -1) {
      // Marker is not in our list of markers.
      return false;
    }
  
    marker.setMap(null);
  
    this.markers_.splice(index, 1);
  
    return true;
  };
  
  
  /**
   * Remove a marker from the cluster.
   *
   * @param {google.maps.Marker} marker The marker to remove.
   * @param {boolean=} opt_nodraw Optional boolean to force no redraw.
   * @return {boolean} True if the marker was removed.
   */
  MarkerClusterer.prototype.removeMarker = function(marker, opt_nodraw) {
    var removed = this.removeMarker_(marker);
  
    if (!opt_nodraw && removed) {
      this.resetViewport();
      this.redraw();
      return true;
    } else {
     return false;
    }
  };
  
  
  /**
   * Removes an array of markers from the cluster.
   *
   * @param {Array.<google.maps.Marker>} markers The markers to remove.
   * @param {boolean=} opt_nodraw Optional boolean to force no redraw.
   */
  MarkerClusterer.prototype.removeMarkers = function(markers, opt_nodraw) {
    var removed = false;
  
    for (var i = 0, marker; marker = markers[i]; i++) {
      var r = this.removeMarker_(marker);
      removed = removed || r;
    }
  
    if (!opt_nodraw && removed) {
      this.resetViewport();
      this.redraw();
      return true;
    }
  };
  
  
  /**
   * Sets the clusterer's ready state.
   *
   * @param {boolean} ready The state.
   * @private
   */
  MarkerClusterer.prototype.setReady_ = function(ready) {
    if (!this.ready_) {
      this.ready_ = ready;
      this.createClusters_();
    }
  };
  
  
  /**
   * Returns the number of clusters in the clusterer.
   *
   * @return {number} The number of clusters.
   */
  MarkerClusterer.prototype.getTotalClusters = function() {
    return this.clusters_.length;
  };
  
  
  /**
   * Returns the google map that the clusterer is associated with.
   *
   * @return {google.maps.Map} The map.
   */
  MarkerClusterer.prototype.getMap = function() {
    return this.map_;
  };
  
  
  /**
   * Sets the google map that the clusterer is associated with.
   *
   * @param {google.maps.Map} map The map.
   */
  MarkerClusterer.prototype.setMap = function(map) {
    this.map_ = map;
  };
  
  
  /**
   * Returns the size of the grid.
   *
   * @return {number} The grid size.
   */
  MarkerClusterer.prototype.getGridSize = function() {
    return this.gridSize_;
  };
  
  
  /**
   * Sets the size of the grid.
   *
   * @param {number} size The grid size.
   */
  MarkerClusterer.prototype.setGridSize = function(size) {
    this.gridSize_ = size;
  };
  
  
  /**
   * Returns the min cluster size.
   *
   * @return {number} The grid size.
   */
  MarkerClusterer.prototype.getMinClusterSize = function() {
    return this.minClusterSize_;
  };
  
  /**
   * Sets the min cluster size.
   *
   * @param {number} size The grid size.
   */
  MarkerClusterer.prototype.setMinClusterSize = function(size) {
    this.minClusterSize_ = size;
  };
  
  
  /**
   * Extends a bounds object by the grid size.
   *
   * @param {google.maps.LatLngBounds} bounds The bounds to extend.
   * @return {google.maps.LatLngBounds} The extended bounds.
   */
  MarkerClusterer.prototype.getExtendedBounds = function(bounds) {
    var projection = this.getProjection();
  
    // Turn the bounds into latlng.
    var tr = new google.maps.LatLng(bounds.getNorthEast().lat(),
        bounds.getNorthEast().lng());
    var bl = new google.maps.LatLng(bounds.getSouthWest().lat(),
        bounds.getSouthWest().lng());
  
    // Convert the points to pixels and the extend out by the grid size.
    var trPix = projection.fromLatLngToDivPixel(tr);
    trPix.x += this.gridSize_;
    trPix.y -= this.gridSize_;
  
    var blPix = projection.fromLatLngToDivPixel(bl);
    blPix.x -= this.gridSize_;
    blPix.y += this.gridSize_;
  
    // Convert the pixel points back to LatLng
    var ne = projection.fromDivPixelToLatLng(trPix);
    var sw = projection.fromDivPixelToLatLng(blPix);
  
    // Extend the bounds to contain the new bounds.
    bounds.extend(ne);
    bounds.extend(sw);
  
    return bounds;
  };
  
  
  /**
   * Determins if a marker is contained in a bounds.
   *
   * @param {google.maps.Marker} marker The marker to check.
   * @param {google.maps.LatLngBounds} bounds The bounds to check against.
   * @return {boolean} True if the marker is in the bounds.
   * @private
   */
  MarkerClusterer.prototype.isMarkerInBounds_ = function(marker, bounds) {
    return bounds.contains(marker.getPosition());
  };
  
  
  /**
   * Clears all clusters and markers from the clusterer.
   */
  MarkerClusterer.prototype.clearMarkers = function() {
    this.resetViewport(true);
  
    // Set the markers a empty array.
    this.markers_ = [];
  };
  
  
  /**
   * Clears all existing clusters and recreates them.
   * @param {boolean} opt_hide To also hide the marker.
   */
  MarkerClusterer.prototype.resetViewport = function(opt_hide) {
    // Remove all the clusters
    for (var i = 0, cluster; cluster = this.clusters_[i]; i++) {
      cluster.remove();
    }
  
    // Reset the markers to not be added and to be invisible.
    for (var i = 0, marker; marker = this.markers_[i]; i++) {
      marker.isAdded = false;
      if (opt_hide) {
        marker.setMap(null);
      }
    }
  
    this.clusters_ = [];
  };
  
  /**
   *
   */
  MarkerClusterer.prototype.repaint = function() {
    var oldClusters = this.clusters_.slice();
    this.clusters_.length = 0;
    this.resetViewport();
    this.redraw();
  
    // Remove the old clusters.
    // Do it in a timeout so the other clusters have been drawn first.
    window.setTimeout(function() {
      for (var i = 0, cluster; cluster = oldClusters[i]; i++) {
        cluster.remove();
      }
    }, 0);
  };
  
  
  /**
   * Redraws the clusters.
   */
  MarkerClusterer.prototype.redraw = function() {
    this.createClusters_();
  };
  
  
  /**
   * Calculates the distance between two latlng locations in km.
   * @see http://www.movable-type.co.uk/scripts/latlong.html
   *
   * @param {google.maps.LatLng} p1 The first lat lng point.
   * @param {google.maps.LatLng} p2 The second lat lng point.
   * @return {number} The distance between the two points in km.
   * @private
  */
  MarkerClusterer.prototype.distanceBetweenPoints_ = function(p1, p2) {
    if (!p1 || !p2) {
      return 0;
    }
  
    var R = 6371; // Radius of the Earth in km
    var dLat = (p2.lat() - p1.lat()) * Math.PI / 180;
    var dLon = (p2.lng() - p1.lng()) * Math.PI / 180;
    var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
      Math.cos(p1.lat() * Math.PI / 180) * Math.cos(p2.lat() * Math.PI / 180) *
      Math.sin(dLon / 2) * Math.sin(dLon / 2);
    var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    var d = R * c;
    return d;
  };
  
  
  /**
   * Add a marker to a cluster, or creates a new cluster.
   *
   * @param {google.maps.Marker} marker The marker to add.
   * @private
   */
  MarkerClusterer.prototype.addToClosestCluster_ = function(marker) {
    var distance = 40000; // Some large number
    var clusterToAddTo = null;
    var pos = marker.getPosition();
    for (var i = 0, cluster; cluster = this.clusters_[i]; i++) {
      var center = cluster.getCenter();
      if (center) {
        var d = this.distanceBetweenPoints_(center, marker.getPosition());
        if (d < distance) {
          distance = d;
          clusterToAddTo = cluster;
        }
      }
    }
  
    if (clusterToAddTo && clusterToAddTo.isMarkerInClusterBounds(marker)) {
      clusterToAddTo.addMarker(marker);
    } else {
      var cluster = new Cluster(this);
      cluster.addMarker(marker);
      this.clusters_.push(cluster);
    }
  };
  
  
  /**
   * Creates the clusters.
   *
   * @private
   */
  MarkerClusterer.prototype.createClusters_ = function() {
    if (!this.ready_) {
      return;
    }
  
    // Get our current map view bounds.
    // Create a new bounds object so we don't affect the map.
    var mapBounds = new google.maps.LatLngBounds(this.map_.getBounds().getSouthWest(),
        this.map_.getBounds().getNorthEast());
    var bounds = this.getExtendedBounds(mapBounds);
  
    for (var i = 0, marker; marker = this.markers_[i]; i++) {
      if (!marker.isAdded && this.isMarkerInBounds_(marker, bounds)) {
        this.addToClosestCluster_(marker);
      }
    }
  };
  
  
  /**
   * A cluster that contains markers.
   *
   * @param {MarkerClusterer} markerClusterer The markerclusterer that this
   *     cluster is associated with.
   * @constructor
   * @ignore
   */
  function Cluster(markerClusterer) {
    this.markerClusterer_ = markerClusterer;
    this.map_ = markerClusterer.getMap();
    this.gridSize_ = markerClusterer.getGridSize();
    this.minClusterSize_ = markerClusterer.getMinClusterSize();
    this.averageCenter_ = markerClusterer.isAverageCenter();
    this.center_ = null;
    this.markers_ = [];
    this.bounds_ = null;
    this.clusterIcon_ = new ClusterIcon(this, markerClusterer.getStyles(),
        markerClusterer.getGridSize());
  }
  
  /**
   * Determins if a marker is already added to the cluster.
   *
   * @param {google.maps.Marker} marker The marker to check.
   * @return {boolean} True if the marker is already added.
   */
  Cluster.prototype.isMarkerAlreadyAdded = function(marker) {
    if (this.markers_.indexOf) {
      return this.markers_.indexOf(marker) != -1;
    } else {
      for (var i = 0, m; m = this.markers_[i]; i++) {
        if (m == marker) {
          return true;
        }
      }
    }
    return false;
  };
  
  
  /**
   * Add a marker the cluster.
   *
   * @param {google.maps.Marker} marker The marker to add.
   * @return {boolean} True if the marker was added.
   */
  Cluster.prototype.addMarker = function(marker) {
    if (this.isMarkerAlreadyAdded(marker)) {
      return false;
    }
  
    if (!this.center_) {
      this.center_ = marker.getPosition();
      this.calculateBounds_();
    } else {
      if (this.averageCenter_) {
        var l = this.markers_.length + 1;
        var lat = (this.center_.lat() * (l-1) + marker.getPosition().lat()) / l;
        var lng = (this.center_.lng() * (l-1) + marker.getPosition().lng()) / l;
        this.center_ = new google.maps.LatLng(lat, lng);
        this.calculateBounds_();
      }
    }
  
    marker.isAdded = true;
    this.markers_.push(marker);
  
    var len = this.markers_.length;
    if (len < this.minClusterSize_ && marker.getMap() != this.map_) {
      // Min cluster size not reached so show the marker.
      marker.setMap(this.map_);
    }
  
    if (len == this.minClusterSize_) {
      // Hide the markers that were showing.
      for (var i = 0; i < len; i++) {
        this.markers_[i].setMap(null);
      }
    }
  
    if (len >= this.minClusterSize_) {
      marker.setMap(null);
    }
  
    this.updateIcon();
    return true;
  };
  
  
  /**
   * Returns the marker clusterer that the cluster is associated with.
   *
   * @return {MarkerClusterer} The associated marker clusterer.
   */
  Cluster.prototype.getMarkerClusterer = function() {
    return this.markerClusterer_;
  };
  
  
  /**
   * Returns the bounds of the cluster.
   *
   * @return {google.maps.LatLngBounds} the cluster bounds.
   */
  Cluster.prototype.getBounds = function() {
    var bounds = new google.maps.LatLngBounds(this.center_, this.center_);
    var markers = this.getMarkers();
    for (var i = 0, marker; marker = markers[i]; i++) {
      bounds.extend(marker.getPosition());
    }
    return bounds;
  };
  
  
  /**
   * Removes the cluster
   */
  Cluster.prototype.remove = function() {
    this.clusterIcon_.remove();
    this.markers_.length = 0;
    delete this.markers_;
  };
  
  
  /**
   * Returns the center of the cluster.
   *
   * @return {number} The cluster center.
   */
  Cluster.prototype.getSize = function() {
    return this.markers_.length;
  };
  
  
  /**
   * Returns the center of the cluster.
   *
   * @return {Array.<google.maps.Marker>} The cluster center.
   */
  Cluster.prototype.getMarkers = function() {
    return this.markers_;
  };
  
  
  /**
   * Returns the center of the cluster.
   *
   * @return {google.maps.LatLng} The cluster center.
   */
  Cluster.prototype.getCenter = function() {
    return this.center_;
  };
  
  
  /**
   * Calculated the extended bounds of the cluster with the grid.
   *
   * @private
   */
  Cluster.prototype.calculateBounds_ = function() {
    var bounds = new google.maps.LatLngBounds(this.center_, this.center_);
    this.bounds_ = this.markerClusterer_.getExtendedBounds(bounds);
  };
  
  
  /**
   * Determines if a marker lies in the clusters bounds.
   *
   * @param {google.maps.Marker} marker The marker to check.
   * @return {boolean} True if the marker lies in the bounds.
   */
  Cluster.prototype.isMarkerInClusterBounds = function(marker) {
    return this.bounds_.contains(marker.getPosition());
  };
  
  
  /**
   * Returns the map that the cluster is associated with.
   *
   * @return {google.maps.Map} The map.
   */
  Cluster.prototype.getMap = function() {
    return this.map_;
  };
  
  
  /**
   * Updates the cluster icon
   */
  Cluster.prototype.updateIcon = function() {
    var zoom = this.map_.getZoom();
    var mz = this.markerClusterer_.getMaxZoom();
  
    if (mz && zoom > mz) {
      // The zoom is greater than our max zoom so show all the markers in cluster.
      for (var i = 0, marker; marker = this.markers_[i]; i++) {
        marker.setMap(this.map_);
      }
      return;
    }
  
    if (this.markers_.length < this.minClusterSize_) {
      // Min cluster size not yet reached.
      this.clusterIcon_.hide();
      return;
    }
  
    var numStyles = this.markerClusterer_.getStyles().length;
    var sums = this.markerClusterer_.getCalculator()(this.markers_, numStyles);
    this.clusterIcon_.setCenter(this.center_);
    this.clusterIcon_.setSums(sums);
    this.clusterIcon_.show();
  };
  
  
  /**
   * A cluster icon
   *
   * @param {Cluster} cluster The cluster to be associated with.
   * @param {Object} styles An object that has style properties:
   *     'url': (string) The image url.
   *     'height': (number) The image height.
   *     'width': (number) The image width.
   *     'anchor': (Array) The anchor position of the label text.
   *     'textColor': (string) The text color.
   *     'textSize': (number) The text size.
   *     'backgroundPosition: (string) The background postition x, y.
   * @param {number=} opt_padding Optional padding to apply to the cluster icon.
   * @constructor
   * @extends google.maps.OverlayView
   * @ignore
   */
  function ClusterIcon(cluster, styles, opt_padding) {
    cluster.getMarkerClusterer().extend(ClusterIcon, google.maps.OverlayView);
  
    this.styles_ = styles;
    this.padding_ = opt_padding || 0;
    this.cluster_ = cluster;
    this.center_ = null;
    this.map_ = cluster.getMap();
    this.div_ = null;
    this.sums_ = null;
    this.visible_ = false;
  
    this.setMap(this.map_);
  }
  
  
  /**
   * Triggers the clusterclick event and zoom's if the option is set.
   *
   * @param {google.maps.MouseEvent} event The event to propagate
   */
  ClusterIcon.prototype.triggerClusterClick = function(event) {
    var markerClusterer = this.cluster_.getMarkerClusterer();
  
    // Trigger the clusterclick event.
    google.maps.event.trigger(markerClusterer, 'clusterclick', this.cluster_, event);
  
    if (markerClusterer.isZoomOnClick()) {
      // Zoom into the cluster.
      this.map_.fitBounds(this.cluster_.getBounds());
    }
  };
  
  
  /**
   * Adding the cluster icon to the dom.
   * @ignore
   */
  ClusterIcon.prototype.onAdd = function() {
    this.div_ = document.createElement('DIV');
    if (this.visible_) {
      var pos = this.getPosFromLatLng_(this.center_);
      this.div_.style.cssText = this.createCss(pos);
      this.div_.innerHTML = this.sums_.text;
    }
  
    var panes = this.getPanes();
    panes.overlayMouseTarget.appendChild(this.div_);
  
    var that = this;
    google.maps.event.addDomListener(this.div_, 'click', function(event) {
      that.triggerClusterClick(event);
    });
  };
  
  
  /**
   * Returns the position to place the div dending on the latlng.
   *
   * @param {google.maps.LatLng} latlng The position in latlng.
   * @return {google.maps.Point} The position in pixels.
   * @private
   */
  ClusterIcon.prototype.getPosFromLatLng_ = function(latlng) {
    var pos = this.getProjection().fromLatLngToDivPixel(latlng);
  
    if (typeof this.iconAnchor_ === 'object' && this.iconAnchor_.length === 2) {
      pos.x -= this.iconAnchor_[0];
      pos.y -= this.iconAnchor_[1];
    } else {
      pos.x -= parseInt(this.width_ / 2, 10);
      pos.y -= parseInt(this.height_ / 2, 10);
    }
    return pos;
  };
  
  
  /**
   * Draw the icon.
   * @ignore
   */
  ClusterIcon.prototype.draw = function() {
    if (this.visible_) {
      var pos = this.getPosFromLatLng_(this.center_);
      this.div_.style.top = pos.y + 'px';
      this.div_.style.left = pos.x + 'px';
    }
  };
  
  
  /**
   * Hide the icon.
   */
  ClusterIcon.prototype.hide = function() {
    if (this.div_) {
      this.div_.style.display = 'none';
    }
    this.visible_ = false;
  };
  
  
  /**
   * Position and show the icon.
   */
  ClusterIcon.prototype.show = function() {
    if (this.div_) {
      var pos = this.getPosFromLatLng_(this.center_);
      this.div_.style.cssText = this.createCss(pos);
      this.div_.style.display = '';
    }
    this.visible_ = true;
  };
  
  
  /**
   * Remove the icon from the map
   */
  ClusterIcon.prototype.remove = function() {
    this.setMap(null);
  };
  
  
  /**
   * Implementation of the onRemove interface.
   * @ignore
   */
  ClusterIcon.prototype.onRemove = function() {
    if (this.div_ && this.div_.parentNode) {
      this.hide();
      this.div_.parentNode.removeChild(this.div_);
      this.div_ = null;
    }
  };
  
  
  /**
   * Set the sums of the icon.
   *
   * @param {Object} sums The sums containing:
   *   'text': (string) The text to display in the icon.
   *   'index': (number) The style index of the icon.
   */
  ClusterIcon.prototype.setSums = function(sums) {
    this.sums_ = sums;
    this.text_ = sums.text;
    this.index_ = sums.index;
    if (this.div_) {
      this.div_.innerHTML = sums.text;
    }
  
    this.useStyle();
  };
  
  
  /**
   * Sets the icon to the the styles.
   */
  ClusterIcon.prototype.useStyle = function() {
    var index = Math.max(0, this.sums_.index - 1);
    index = Math.min(this.styles_.length - 1, index);
    var style = this.styles_[index];
    this.url_ = style['url'];
    this.height_ = style['height'];
    this.width_ = style['width'];
    this.textColor_ = style['textColor'];
    this.anchor_ = style['anchor'];
    this.textSize_ = style['textSize'];
    this.backgroundPosition_ = style['backgroundPosition'];
    this.iconAnchor_ = style['iconAnchor'];
  };
  
  
  /**
   * Sets the center of the icon.
   *
   * @param {google.maps.LatLng} center The latlng to set as the center.
   */
  ClusterIcon.prototype.setCenter = function(center) {
    this.center_ = center;
  };
  
  
  /**
   * Create the css text based on the position of the icon.
   *
   * @param {google.maps.Point} pos The position.
   * @return {string} The css style text.
   */
  ClusterIcon.prototype.createCss = function(pos) {
    var style = [];
    style.push('background-image:url(' + this.url_ + ');');
    var backgroundPosition = this.backgroundPosition_ ? this.backgroundPosition_ : '0 0';
    style.push('background-position:' + backgroundPosition + ';');
  
    if (typeof this.anchor_ === 'object') {
      if (typeof this.anchor_[0] === 'number' && this.anchor_[0] > 0 &&
          this.anchor_[0] < this.height_) {
        style.push('height:' + (this.height_ - this.anchor_[0]) +
            'px; padding-top:' + this.anchor_[0] + 'px;');
      } else if (typeof this.anchor_[0] === 'number' && this.anchor_[0] < 0 &&
          -this.anchor_[0] < this.height_) {
        style.push('height:' + this.height_ + 'px; line-height:' + (this.height_ + this.anchor_[0]) +
            'px;');
      } else {
        style.push('height:' + this.height_ + 'px; line-height:' + this.height_ +
            'px;');
      }
      if (typeof this.anchor_[1] === 'number' && this.anchor_[1] > 0 &&
          this.anchor_[1] < this.width_) {
        style.push('width:' + (this.width_ - this.anchor_[1]) +
            'px; padding-left:' + this.anchor_[1] + 'px;');
      } else {
        style.push('width:' + this.width_ + 'px; text-align:center;');
      }
    } else {
      style.push('height:' + this.height_ + 'px; line-height:' +
          this.height_ + 'px; width:' + this.width_ + 'px; text-align:center;');
    }
  
    var txtColor = this.textColor_ ? this.textColor_ : 'black';
    var txtSize = this.textSize_ ? this.textSize_ : 11;
  
    style.push('cursor:pointer; top:' + pos.y + 'px; left:' +
        pos.x + 'px; color:' + txtColor + '; position:absolute; font-size:' +
        txtSize + 'px; font-family:Arial,sans-serif; font-weight:bold');
    return style.join('');
  };
  
  
  // Export Symbols for Closure
  // If you are not going to compile with closure then you can remove the
  // code below.
  window['MarkerClusterer'] = MarkerClusterer;
  MarkerClusterer.prototype['addMarker'] = MarkerClusterer.prototype.addMarker;
  MarkerClusterer.prototype['addMarkers'] = MarkerClusterer.prototype.addMarkers;
  MarkerClusterer.prototype['clearMarkers'] =
      MarkerClusterer.prototype.clearMarkers;
  MarkerClusterer.prototype['fitMapToMarkers'] =
      MarkerClusterer.prototype.fitMapToMarkers;
  MarkerClusterer.prototype['getCalculator'] =
      MarkerClusterer.prototype.getCalculator;
  MarkerClusterer.prototype['getGridSize'] =
      MarkerClusterer.prototype.getGridSize;
  MarkerClusterer.prototype['getExtendedBounds'] =
      MarkerClusterer.prototype.getExtendedBounds;
  MarkerClusterer.prototype['getMap'] = MarkerClusterer.prototype.getMap;
  MarkerClusterer.prototype['getMarkers'] = MarkerClusterer.prototype.getMarkers;
  MarkerClusterer.prototype['getMaxZoom'] = MarkerClusterer.prototype.getMaxZoom;
  MarkerClusterer.prototype['getStyles'] = MarkerClusterer.prototype.getStyles;
  MarkerClusterer.prototype['getTotalClusters'] =
      MarkerClusterer.prototype.getTotalClusters;
  MarkerClusterer.prototype['getTotalMarkers'] =
      MarkerClusterer.prototype.getTotalMarkers;
  MarkerClusterer.prototype['redraw'] = MarkerClusterer.prototype.redraw;
  MarkerClusterer.prototype['removeMarker'] =
      MarkerClusterer.prototype.removeMarker;
  MarkerClusterer.prototype['removeMarkers'] =
      MarkerClusterer.prototype.removeMarkers;
  MarkerClusterer.prototype['resetViewport'] =
      MarkerClusterer.prototype.resetViewport;
  MarkerClusterer.prototype['repaint'] =
      MarkerClusterer.prototype.repaint;
  MarkerClusterer.prototype['setCalculator'] =
      MarkerClusterer.prototype.setCalculator;
  MarkerClusterer.prototype['setGridSize'] =
      MarkerClusterer.prototype.setGridSize;
  MarkerClusterer.prototype['setMaxZoom'] =
      MarkerClusterer.prototype.setMaxZoom;
  MarkerClusterer.prototype['onAdd'] = MarkerClusterer.prototype.onAdd;
  MarkerClusterer.prototype['draw'] = MarkerClusterer.prototype.draw;
  
  Cluster.prototype['getCenter'] = Cluster.prototype.getCenter;
  Cluster.prototype['getSize'] = Cluster.prototype.getSize;
  Cluster.prototype['getMarkers'] = Cluster.prototype.getMarkers;
  
  ClusterIcon.prototype['onAdd'] = ClusterIcon.prototype.onAdd;
  ClusterIcon.prototype['draw'] = ClusterIcon.prototype.draw;
  ClusterIcon.prototype['onRemove'] = ClusterIcon.prototype.onRemove;
  