Blame | Last modification | View Log | RSS feed
/*** @name MarkerClusterer* @version 1.0* @author Xiaoxi Wu* @copyright (c) 2009 Xiaoxi Wu* @fileoverview* This javascript library creates and manages per-zoom-level* clusters for large amounts of markers (hundreds or thousands).* This library was inspired by the <a href="http://www.maptimize.com">* Maptimize</a> hosted clustering solution.* <br /><br/>* <b>How it works</b>:<br/>* The <code>MarkerClusterer</code> will group markers into clusters according to* their distance from a cluster's center. When a marker is added,* the marker cluster will find a position in all the clusters, and* if it fails to find one, it will create a new cluster with the marker.* The number of markers in a cluster will be displayed* on the cluster marker. When the map viewport changes,* <code>MarkerClusterer</code> will destroy the clusters in the viewport* and regroup them into new clusters.**//** 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.*//*** @name MarkerClustererOptions* @class This class represents optional arguments to the {@link MarkerClusterer}* constructor.* @property {Number} [maxZoom] The max zoom level monitored by a* marker cluster. If not given, the marker cluster assumes the maximum map* zoom level. When maxZoom is reached or exceeded all markers will be shown* without cluster.* @property {Number} [gridSize=60] The grid size of a cluster in pixel. Each* cluster will be a square. If you want the algorithm to run faster, you can set* this value larger.* @property {Array of MarkerStyleOptions} [styles]* Custom styles for the cluster markers.* The array should be ordered according to increasing cluster size,* with the style for the smallest clusters first, and the style for the* largest clusters last.*//*** @name MarkerStyleOptions* @class An array of these is passed into the {@link MarkerClustererOptions}* styles option.* @property {String} [url] Image url.* @property {Number} [height] Image height.* @property {Number} [height] Image width.* @property {Array of Number} [opt_anchor] Anchor for label text, like [24, 12].* If not set, the text will align center and middle.* @property {String} [opt_textColor="black"] Text color.*//*** Creates a new MarkerClusterer to cluster markers on the map.** @constructor* @param {GMap2} map The map that the markers should be added to.* @param {Array of GMarker} opt_markers Initial set of markers to be clustered.* @param {MarkerClustererOptions} opt_opts A container for optional arguments.*/function MarkerClusterer(map, opt_markers, opt_opts) {// private membersvar clusters_ = [];var map_ = map;var maxZoom_ = null;var me_ = this;var gridSize_ = 60;var sizes = [53, 56, 66, 78, 90];var styles_ = [];var leftMarkers_ = [];var mcfn_ = null;var i = 0;for (i = 1; i <= 5; ++i) {styles_.push({'url': "http://gmaps-utility-library.googlecode.com/svn/trunk/markerclusterer/images/m" + i + ".png",'height': sizes[i - 1],'width': sizes[i - 1]});}if (typeof opt_opts === "object" && opt_opts !== null) {if (typeof opt_opts.gridSize === "number" && opt_opts.gridSize > 0) {gridSize_ = opt_opts.gridSize;}if (typeof opt_opts.maxZoom === "number") {maxZoom_ = opt_opts.maxZoom;}if (typeof opt_opts.styles === "object" && opt_opts.styles !== null && opt_opts.styles.length !== 0) {styles_ = opt_opts.styles;}}/*** When we add a marker, the marker may not in the viewport of map, then we don't deal with it, instead* we add the marker into a array called leftMarkers_. When we reset MarkerClusterer we should add the* leftMarkers_ into MarkerClusterer.*/function addLeftMarkers_() {if (leftMarkers_.length === 0) {return;}var leftMarkers = [];for (i = 0; i < leftMarkers_.length; ++i) {me_.addMarker(leftMarkers_[i], true, null, null, true);}leftMarkers_ = leftMarkers;}/*** Get cluster marker images of this marker cluster. Mostly used by {@link Cluster}* @private* @return {Array of String}*/this.getStyles_ = function () {return styles_;};/*** Remove all markers from MarkerClusterer.*/this.clearMarkers = function () {for (var i = 0; i < clusters_.length; ++i) {if (typeof clusters_[i] !== "undefined" && clusters_[i] !== null) {clusters_[i].clearMarkers();}}clusters_ = [];leftMarkers_ = [];GEvent.removeListener(mcfn_);};/*** Check a marker, whether it is in current map viewport.* @private* @return {Boolean} if it is in current map viewport*/function isMarkerInViewport_(marker) {return map_.getBounds().containsLatLng(marker.getLatLng());}/*** When reset MarkerClusterer, there will be some markers get out of its cluster.* These markers should be add to new clusters.* @param {Array of GMarker} markers Markers to add.*/function reAddMarkers_(markers) {var len = markers.length;var clusters = [];for (var i = len - 1; i >= 0; --i) {me_.addMarker(markers[i].marker, true, markers[i].isAdded, clusters, true);}addLeftMarkers_();}/*** Add a marker.* @private* @param {GMarker} marker Marker you want to add* @param {Boolean} opt_isNodraw Whether redraw the cluster contained the marker* @param {Boolean} opt_isAdded Whether the marker is added to map. Never use it.* @param {Array of Cluster} opt_clusters Provide a list of clusters, the marker* cluster will only check these cluster where the marker should join.*/this.addMarker = function (marker, opt_isNodraw, opt_isAdded, opt_clusters, opt_isNoCheck) {if (opt_isNoCheck !== true) {if (!isMarkerInViewport_(marker)) {leftMarkers_.push(marker);return;}}var isAdded = opt_isAdded;var clusters = opt_clusters;var pos = map_.fromLatLngToDivPixel(marker.getLatLng());if (typeof isAdded !== "boolean") {isAdded = false;}if (typeof clusters !== "object" || clusters === null) {clusters = clusters_;}var length = clusters.length;var cluster = null;for (var i = length - 1; i >= 0; i--) {cluster = clusters[i];var center = cluster.getCenter();if (center === null) {continue;}center = map_.fromLatLngToDivPixel(center);// Found a cluster which contains the marker.if (pos.x >= center.x - gridSize_ && pos.x <= center.x + gridSize_ &&pos.y >= center.y - gridSize_ && pos.y <= center.y + gridSize_) {cluster.addMarker({'isAdded': isAdded,'marker': marker});if (!opt_isNodraw) {cluster.redraw_();}return;}}// No cluster contain the marker, create a new cluster.cluster = new Cluster(this, map);cluster.addMarker({'isAdded': isAdded,'marker': marker});if (!opt_isNodraw) {cluster.redraw_();}// Add this cluster both in clusters provided and clusters_clusters.push(cluster);if (clusters !== clusters_) {clusters_.push(cluster);}};/*** Remove a marker.** @param {GMarker} marker The marker you want to remove.*/this.removeMarker = function (marker) {for (var i = 0; i < clusters_.length; ++i) {if (clusters_[i].remove(marker)) {clusters_[i].redraw_();return;}}};/*** Redraw all clusters in viewport.*/this.redraw_ = function () {var clusters = this.getClustersInViewport_();for (var i = 0; i < clusters.length; ++i) {clusters[i].redraw_(true);}};/*** Get all clusters in viewport.* @return {Array of Cluster}*/this.getClustersInViewport_ = function () {var clusters = [];var curBounds = map_.getBounds();for (var i = 0; i < clusters_.length; i ++) {if (clusters_[i].isInBounds(curBounds)) {clusters.push(clusters_[i]);}}return clusters;};/*** Get max zoom level.* @private* @return {Number}*/this.getMaxZoom_ = function () {return maxZoom_;};/*** Get map object.* @private* @return {GMap2}*/this.getMap_ = function () {return map_;};/*** Get grid size* @private* @return {Number}*/this.getGridSize_ = function () {return gridSize_;};/*** Get total number of markers.* @return {Number}*/this.getTotalMarkers = function () {var result = 0;for (var i = 0; i < clusters_.length; ++i) {result += clusters_[i].getTotalMarkers();}return result;};/*** Get total number of clusters.* @return {int}*/this.getTotalClusters = function () {return clusters_.length;};/*** Collect all markers of clusters in viewport and regroup them.*/this.resetViewport = function () {var clusters = this.getClustersInViewport_();var tmpMarkers = [];var removed = 0;for (var i = 0; i < clusters.length; ++i) {var cluster = clusters[i];var oldZoom = cluster.getCurrentZoom();if (oldZoom === null) {continue;}var curZoom = map_.getZoom();if (curZoom !== oldZoom) {// If the cluster zoom level changed then destroy the cluster// and collect its markers.var mks = cluster.getMarkers();for (var j = 0; j < mks.length; ++j) {var newMarker = {'isAdded': false,'marker': mks[j].marker};tmpMarkers.push(newMarker);}cluster.clearMarkers();removed++;for (j = 0; j < clusters_.length; ++j) {if (cluster === clusters_[j]) {clusters_.splice(j, 1);}}}}// Add the markers collected into marker cluster to resetreAddMarkers_(tmpMarkers);this.redraw_();};/*** Add a set of markers.** @param {Array of GMarker} markers The markers you want to add.*/this.addMarkers = function (markers) {for (var i = 0; i < markers.length; ++i) {this.addMarker(markers[i], true);}this.redraw_();};// initializeif (typeof opt_markers === "object" && opt_markers !== null) {this.addMarkers(opt_markers);}// when map move end, regroup.mcfn_ = GEvent.addListener(map_, "moveend", function () {me_.resetViewport();});}/*** Create a cluster to collect markers.* A cluster includes some markers which are in a block of area.* If there are more than one markers in cluster, the cluster* will create a {@link ClusterMarker_} and show the total number* of markers in cluster.** @constructor* @private* @param {MarkerClusterer} markerClusterer The marker cluster object*/function Cluster(markerClusterer) {var center_ = null;var markers_ = [];var markerClusterer_ = markerClusterer;var map_ = markerClusterer.getMap_();var clusterMarker_ = null;var zoom_ = map_.getZoom();/*** Get markers of this cluster.** @return {Array of GMarker}*/this.getMarkers = function () {return markers_;};/*** If this cluster intersects certain bounds.** @param {GLatLngBounds} bounds A bounds to test* @return {Boolean} Is this cluster intersects the bounds*/this.isInBounds = function (bounds) {if (center_ === null) {return false;}if (!bounds) {bounds = map_.getBounds();}var sw = map_.fromLatLngToDivPixel(bounds.getSouthWest());var ne = map_.fromLatLngToDivPixel(bounds.getNorthEast());var centerxy = map_.fromLatLngToDivPixel(center_);var inViewport = true;var gridSize = markerClusterer.getGridSize_();if (zoom_ !== map_.getZoom()) {var dl = map_.getZoom() - zoom_;gridSize = Math.pow(2, dl) * gridSize;}if (ne.x !== sw.x && (centerxy.x + gridSize < sw.x || centerxy.x - gridSize > ne.x)) {inViewport = false;}if (inViewport && (centerxy.y + gridSize < ne.y || centerxy.y - gridSize > sw.y)) {inViewport = false;}return inViewport;};/*** Get cluster center.** @return {GLatLng}*/this.getCenter = function () {return center_;};/*** Add a marker.** @param {Object} marker An object of marker you want to add:* {Boolean} isAdded If the marker is added on map.* {GMarker} marker The marker you want to add.*/this.addMarker = function (marker) {if (center_ === null) {/*var pos = marker['marker'].getLatLng();pos = map.fromLatLngToContainerPixel(pos);pos.x = parseInt(pos.x - pos.x % (GRIDWIDTH * 2) + GRIDWIDTH);pos.y = parseInt(pos.y - pos.y % (GRIDWIDTH * 2) + GRIDWIDTH);center = map.fromContainerPixelToLatLng(pos);*/center_ = marker.marker.getLatLng();}markers_.push(marker);};/*** Remove a marker from cluster.** @param {GMarker} marker The marker you want to remove.* @return {Boolean} Whether find the marker to be removed.*/this.removeMarker = function (marker) {for (var i = 0; i < markers_.length; ++i) {if (marker === markers_[i].marker) {if (markers_[i].isAdded) {map_.removeOverlay(markers_[i].marker);}markers_.splice(i, 1);return true;}}return false;};/*** Get current zoom level of this cluster.* Note: the cluster zoom level and map zoom level not always the same.** @return {Number}*/this.getCurrentZoom = function () {return zoom_;};/*** Redraw a cluster.* @private* @param {Boolean} isForce If redraw by force, no matter if the cluster is* in viewport.*/this.redraw_ = function (isForce) {if (!isForce && !this.isInBounds()) {return;}// Set cluster zoom level.zoom_ = map_.getZoom();var i = 0;var mz = markerClusterer.getMaxZoom_();if (mz === null) {mz = map_.getCurrentMapType().getMaximumResolution();}if (zoom_ >= mz || this.getTotalMarkers() === 1) {// If current zoom level is beyond the max zoom level or the cluster// have only one marker, the marker(s) in cluster will be showed on map.for (i = 0; i < markers_.length; ++i) {if (markers_[i].isAdded) {if (markers_[i].marker.isHidden()) {markers_[i].marker.show();}} else {map_.addOverlay(markers_[i].marker);markers_[i].isAdded = true;}}if (clusterMarker_ !== null) {clusterMarker_.hide();}} else {// Else add a cluster marker on map to show the number of markers in// this cluster.for (i = 0; i < markers_.length; ++i) {if (markers_[i].isAdded && (!markers_[i].marker.isHidden())) {markers_[i].marker.hide();}}if (clusterMarker_ === null) {clusterMarker_ = new ClusterMarker_(center_, this.getTotalMarkers(), markerClusterer_.getStyles_(), markerClusterer_.getGridSize_());map_.addOverlay(clusterMarker_);} else {if (clusterMarker_.isHidden()) {clusterMarker_.show();}clusterMarker_.redraw(true);}}};/*** Remove all the markers from this cluster.*/this.clearMarkers = function () {if (clusterMarker_ !== null) {map_.removeOverlay(clusterMarker_);}for (var i = 0; i < markers_.length; ++i) {if (markers_[i].isAdded) {map_.removeOverlay(markers_[i].marker);}}markers_ = [];};/*** Get number of markers.* @return {Number}*/this.getTotalMarkers = function () {return markers_.length;};}/*** ClusterMarker_ creates a marker that shows the number of markers that* a cluster contains.** @constructor* @private* @param {GLatLng} latlng Marker's lat and lng.* @param {Number} count Number to show.* @param {Array of Object} styles The image list to be showed:* {String} url Image url.* {Number} height Image height.* {Number} width Image width.* {Array of Number} anchor Text anchor of image left and top.* {String} textColor text color.* @param {Number} padding Padding of marker center.*/function ClusterMarker_(latlng, count, styles, padding) {var index = 0;var dv = count;while (dv !== 0) {dv = parseInt(dv / 10, 10);index ++;}if (styles.length < index) {index = styles.length;}this.url_ = styles[index - 1].url;this.height_ = styles[index - 1].height;this.width_ = styles[index - 1].width;this.textColor_ = styles[index - 1].opt_textColor;this.anchor_ = styles[index - 1].opt_anchor;this.latlng_ = latlng;this.index_ = index;this.styles_ = styles;this.text_ = count;this.padding_ = padding;}ClusterMarker_.prototype = new GOverlay();/*** Initialize cluster marker.* @private*/ClusterMarker_.prototype.initialize = function (map) {this.map_ = map;var div = document.createElement("div");var latlng = this.latlng_;var pos = map.fromLatLngToDivPixel(latlng);pos.x -= parseInt(this.width_ / 2, 10);pos.y -= parseInt(this.height_ / 2, 10);var mstyle = "";if (document.all) {mstyle = 'filter:progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale,src="' + this.url_ + '");';} else {mstyle = "background:url(" + this.url_ + ");";}if (typeof this.anchor_ === "object") {if (typeof this.anchor_[0] === "number" && this.anchor_[0] > 0 && this.anchor_[0] < this.height_) {mstyle += 'height:' + (this.height_ - this.anchor_[0]) + 'px;padding-top:' + this.anchor_[0] + 'px;';} else {mstyle += 'height:' + this.height_ + 'px;line-height:' + this.height_ + 'px;';}if (typeof this.anchor_[1] === "number" && this.anchor_[1] > 0 && this.anchor_[1] < this.width_) {mstyle += 'width:' + (this.width_ - this.anchor_[1]) + 'px;padding-left:' + this.anchor_[1] + 'px;';} else {mstyle += 'width:' + this.width_ + 'px;text-align:center;';}} else {mstyle += 'height:' + this.height_ + 'px;line-height:' + this.height_ + 'px;';mstyle += 'width:' + this.width_ + 'px;text-align:center;';}var txtColor = this.textColor_ ? this.textColor_ : 'black';div.style.cssText = mstyle + 'cursor:pointer;top:' + pos.y + "px;left:" +pos.x + "px;color:" + txtColor + ";position:absolute;font-size:11px;" +'font-family:Arial,sans-serif;font-weight:bold';div.innerHTML = this.text_;map.getPane(G_MAP_MAP_PANE).appendChild(div);var padding = this.padding_;GEvent.addDomListener(div, "click", function () {var pos = map.fromLatLngToDivPixel(latlng);var sw = new GPoint(pos.x - padding, pos.y + padding);sw = map.fromDivPixelToLatLng(sw);var ne = new GPoint(pos.x + padding, pos.y - padding);ne = map.fromDivPixelToLatLng(ne);var zoom = map.getBoundsZoomLevel(new GLatLngBounds(sw, ne), map.getSize());map.setCenter(latlng, zoom);});this.div_ = div;};/*** Remove this overlay.* @private*/ClusterMarker_.prototype.remove = function () {this.div_.parentNode.removeChild(this.div_);};/*** Copy this overlay.* @private*/ClusterMarker_.prototype.copy = function () {return new ClusterMarker_(this.latlng_, this.index_, this.text_, this.styles_, this.padding_);};/*** Redraw this overlay.* @private*/ClusterMarker_.prototype.redraw = function (force) {if (!force) {return;}var pos = this.map_.fromLatLngToDivPixel(this.latlng_);pos.x -= parseInt(this.width_ / 2, 10);pos.y -= parseInt(this.height_ / 2, 10);this.div_.style.top = pos.y + "px";this.div_.style.left = pos.x + "px";};/*** Hide this cluster marker.*/ClusterMarker_.prototype.hide = function () {this.div_.style.display = "none";};/*** Show this cluster marker.*/ClusterMarker_.prototype.show = function () {this.div_.style.display = "";};/*** Get whether the cluster marker is hidden.* @return {Boolean}*/ClusterMarker_.prototype.isHidden = function () {return this.div_.style.display === "none";};