百度的MAP的例子里提供了一个聚合效果，地址是http://developer.baidu.com/map/jsdemo.htm#c1_4 ，效果图如下图：
这个效果很赞，但效率很低，当数据量达到5000的时候就难以忍受了，加载和地图缩放都很卡，用户体验很差劲。官方提供的MarkerClusterer.js 文件是这样的：
/**
* @fileoverview MarkerClusterer标记聚合器用来解决加载大量点要素到地图上产生覆盖现象的问题，并提高性能。
* 主入口类是<a href="symbols/BMapLib.MarkerClusterer.html">MarkerClusterer</a>，
* 基于Baidu Map API 1.2。
*
* @author Baidu Map Api Group
* @version 1.2
*/
/**
* @namespace BMap的所有library类均放在BMapLib命名空间下
*/
var BMapLib = window.BMapLib = BMapLib || {};
(function(){
/**
* 获取一个扩展的视图范围，把上下左右都扩大一样的像素值。
* @param {Map} map BMap.Map的实例化对象
* @param {BMap.Bounds} bounds BMap.Bounds的实例化对象
* @param {Number} gridSize 要扩大的像素值
*
* @return {BMap.Bounds} 返回扩大后的视图范围。
*/
var getExtendedBounds = function(map, bounds, gridSize){
bounds = cutBoundsInRange(bounds);
var pixelNE = map.pointToPixel(bounds.getNorthEast());
var pixelSW = map.pointToPixel(bounds.getSouthWest());
pixelNE.x += gridSize;
pixelNE.y -= gridSize;
pixelSW.x -= gridSize;
pixelSW.y += gridSize;
var newNE = map.pixelToPoint(pixelNE);
var newSW = map.pixelToPoint(pixelSW);
return new BMap.Bounds(newSW, newNE);
};
/**
* 按照百度地图支持的世界范围对bounds进行边界处理
* @param {BMap.Bounds} bounds BMap.Bounds的实例化对象
*
* @return {BMap.Bounds} 返回不越界的视图范围
*/
var cutBoundsInRange = function (bounds) {
var maxX = getRange(bounds.getNorthEast().lng, -180, 180);
var minX = getRange(bounds.getSouthWest().lng, -180, 180);
var maxY = getRange(bounds.getNorthEast().lat, -74, 74);
var minY = getRange(bounds.getSouthWest().lat, -74, 74);
return new BMap.Bounds(new BMap.Point(minX, minY), new BMap.Point(maxX, maxY));
};
/**
* 对单个值进行边界处理。
* @param {Number} i 要处理的数值
* @param {Number} min 下边界值
* @param {Number} max 上边界值
*
* @return {Number} 返回不越界的数值
*/
var getRange = function (i, mix, max) {
mix && (i = Math.max(i, mix));
max && (i = Math.min(i, max));
return i;
};
/**
* 判断给定的对象是否为数组
* @param {Object} source 要测试的对象
*
* @return {Boolean} 如果是数组返回true，否则返回false
*/
var isArray = function (source) {
return ‘[object Array]‘ === Object.prototype.toString.call(source);
};
/**
* 返回item在source中的索引位置
* @param {Object} item 要测试的对象
* @param {Array} source 数组
*
* @return {Number} 如果在数组内，返回索引，否则返回-1
*/
var indexOf = function(item, source){
var index = -1;
if(isArray(source)){
if (source.indexOf) {
index = source.indexOf(item);
} else {
for (var i = 0, m; m = source[i]; i++) {
if (m === item) {
index = i;
break;
}
}
}
}
return index;
};
/**
*@exports MarkerClusterer as BMapLib.MarkerClusterer
*/
var MarkerClusterer =
/**
* MarkerClusterer
* @class 用来解决加载大量点要素到地图上产生覆盖现象的问题，并提高性能
* @constructor
* @param {Map} map 地图的一个实例。
* @param {Json Object} options 可选参数，可选项包括：<br />
* markers {Array<Marker>} 要聚合的标记数组<br />
* girdSize {Number} 聚合计算时网格的像素大小，默认60<br />
* maxZoom {Number} 最大的聚合级别，大于该级别就不进行相应的聚合<br />
* minClusterSize {Number} 最小的聚合数量，小于该数量的不能成为一个聚合，默认为2<br />
* isAverangeCenter {Boolean} 聚合点的落脚位置是否是所有聚合在内点的平均值，默认为否，落脚在聚合内的第一个点<br />
* styles {Array<IconStyle>} 自定义聚合后的图标风格，请参考TextIconOverlay类<br />
*/
BMapLib.MarkerClusterer = function(map, options){
if (!map){
return;
}
this._map = map;
this._markers = [];
this._clusters = [];
var opts = options || {};
this._gridSize = opts["gridSize"] || 60;
this._maxZoom = opts["maxZoom"] || 18;
this._minClusterSize = opts["minClusterSize"] || 2;
this._isAverageCenter = false;
if (opts[‘isAverageCenter‘] != undefined) {
this._isAverageCenter = opts[‘isAverageCenter‘];
}
this._styles = opts["styles"] || [];
var that = this;
this._map.addEventListener("zoomend",function(){
that._redraw();
});
this._map.addEventListener("moveend",function(){
that._redraw();
});
var mkrs = opts["markers"];
isArray(mkrs) && this.addMarkers(mkrs);
};
/**
* 添加要聚合的标记数组。
* @param {Array<Marker>} markers 要聚合的标记数组
*
* @return 无返回值。
*/
MarkerClusterer.prototype.addMarkers = function(markers){
for(var i = 0, len = markers.length; i <len ; i++){
this._pushMarkerTo(markers[i]);
}
this._createClusters();
};
/**
* 把一个标记添加到要聚合的标记数组中
* @param {BMap.Marker} marker 要添加的标记
*
* @return 无返回值。
*/
MarkerClusterer.prototype._pushMarkerTo = function(marker){
var index = indexOf(marker, this._markers);
if(index === -1){
marker.isInCluster = false;
this._markers.push(marker);//Marker拖放后enableDragging不做变化，忽略
}
};
/**
* 添加一个聚合的标记。
* @param {BMap.Marker} marker 要聚合的单个标记。
* @return 无返回值。
*/
MarkerClusterer.prototype.addMarker = function(marker) {
this._pushMarkerTo(marker);
this._createClusters();
};
/**
* 根据所给定的标记，创建聚合点
* @return 无返回值
*/
MarkerClusterer.prototype._createClusters = function(){
var mapBounds = this._map.getBounds();
var extendedBounds = getExtendedBounds(this._map, mapBounds, this._gridSize);
for(var i = 0, marker; marker = this._markers[i]; i++){
if(!marker.isInCluster && extendedBounds.containsPoint(marker.getPosition()) ){
this._addToClosestCluster(marker);
}
}
};
/**
* 根据标记的位置，把它添加到最近的聚合中
* @param {BMap.Marker} marker 要进行聚合的单个标记
*
* @return 无返回值。
*/
MarkerClusterer.prototype._addToClosestCluster = function (marker){
var distance = 4000000;
var clusterToAddTo = null;
var position = marker.getPosition();
for(var i = 0, cluster; cluster = this._clusters[i]; i++){
var center = cluster.getCenter();
if(center){
var d = this._map.getDistance(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);
}
};
/**
* 清除上一次的聚合的结果
* @return 无返回值。
*/
MarkerClusterer.prototype._clearLastClusters = function(){
for(var i = 0, cluster; cluster = this._clusters[i]; i++){
cluster.remove();
}
this._clusters = [];//置空Cluster数组
this._removeMarkersFromCluster();//把Marker的cluster标记设为false
};
/**
* 清除某个聚合中的所有标记
* @return 无返回值
*/
MarkerClusterer.prototype._removeMarkersFromCluster = function(){
for(var i = 0, marker; marker = this._markers[i]; i++){
marker.isInCluster = false;
}
};
/**
* 把所有的标记从地图上清除
* @return 无返回值
*/
MarkerClusterer.prototype._removeMarkersFromMap = function(){
for(var i = 0, marker; marker = this._markers[i]; i++){
marker.isInCluster = false;
this._map.removeOverlay(marker);
}
};
/**
* 删除单个标记
* @param {BMap.Marker} marker 需要被删除的marker
*
* @return {Boolean} 删除成功返回true，否则返回false
*/
MarkerClusterer.prototype._removeMarker = function(marker) {
var index = indexOf(marker, this._markers);
if (index === -1) {
return false;
}
this._map.removeOverlay(marker);
this._markers.splice(index, 1);
return true;
};
/**
* 删除单个标记
* @param {BMap.Marker} marker 需要被删除的marker
*
* @return {Boolean} 删除成功返回true，否则返回false
*/
MarkerClusterer.prototype.removeMarker = function(marker) {
var success = this._removeMarker(marker);
if (success) {
this._clearLastClusters();
this._createClusters();
}
return success;
};
/**
* 删除一组标记
* @param {Array<BMap.Marker>} markers 需要被删除的marker数组
*
* @return {Boolean} 删除成功返回true，否则返回false
*/
MarkerClusterer.prototype.removeMarkers = function(markers) {
var success = false;
for (var i = 0; i < markers.length; i++) {
var r = this._removeMarker(markers[i]);
success = success || r;
}
if (success) {
this._clearLastClusters();
this._createClusters();
}
return success;
};
/**
* 从地图上彻底清除所有的标记
* @return 无返回值
*/
MarkerClusterer.prototype.clearMarkers = function() {
this._clearLastClusters();
this._removeMarkersFromMap();
this._markers = [];
};
/**
* 重新生成，比如改变了属性等
* @return 无返回值
*/
MarkerClusterer.prototype._redraw = function () {
this._clearLastClusters();
this._createClusters();
};
/**
* 获取网格大小
* @return {Number} 网格大小
*/
MarkerClusterer.prototype.getGridSize = function() {
return this._gridSize;
};
/**
* 设置网格大小
* @param {Number} size 网格大小
* @return 无返回值
*/
MarkerClusterer.prototype.setGridSize = function(size) {
this._gridSize = size;
this._redraw();
};
/**
* 获取聚合的最大缩放级别。
* @return {Number} 聚合的最大缩放级别。
*/
MarkerClusterer.prototype.getMaxZoom = function() {
return this._maxZoom;
};
/**
* 设置聚合的最大缩放级别
* @param {Number} maxZoom 聚合的最大缩放级别
* @return 无返回值
*/
MarkerClusterer.prototype.setMaxZoom = function(maxZoom) {
this._maxZoom = maxZoom;
this._redraw();
};
/**
* 获取聚合的样式风格集合
* @return {Array<IconStyle>} 聚合的样式风格集合
*/
MarkerClusterer.prototype.getStyles = function() {
return this._styles;
};
/**
* 设置聚合的样式风格集合
* @param {Array<IconStyle>} styles 样式风格数组
* @return 无返回值
*/
MarkerClusterer.prototype.setStyles = function(styles) {
this._styles = styles;
this._redraw();
};
/**
* 获取单个聚合的最小数量。
* @return {Number} 单个聚合的最小数量。
*/
MarkerClusterer.prototype.getMinClusterSize = function() {
return this._minClusterSize;
};
/**
* 设置单个聚合的最小数量。
* @param {Number} size 单个聚合的最小数量。
* @return 无返回值。
*/
MarkerClusterer.prototype.setMinClusterSize = function(size) {
this._minClusterSize = size;
this._redraw();
};
/**
* 获取单个聚合的落脚点是否是聚合内所有标记的平均中心。
* @return {Boolean} true或false。
*/
MarkerClusterer.prototype.isAverageCenter = function() {
return this._isAverageCenter;
};
/**
* 获取聚合的Map实例。
* @return {Map} Map的示例。
*/
MarkerClusterer.prototype.getMap = function() {
return this._map;
};
/**
* 获取所有的标记数组。
* @return {Array<Marker>} 标记数组。
*/
MarkerClusterer.prototype.getMarkers = function() {
return this._markers;
};
/**
* 获取聚合的总数量。
* @return {Number} 聚合的总数量。
*/
MarkerClusterer.prototype.getClustersCount = function() {
var count = 0;
for(var i = 0, cluster; cluster = this._clusters[i]; i++){
cluster.isReal() && count++;
}
return count;
};
/**
* @ignore
* Cluster
* @class 表示一个聚合对象，该聚合，包含有N个标记，这N个标记组成的范围，并有予以显示在Map上的TextIconOverlay等。
* @constructor
* @param {MarkerClusterer} markerClusterer 一个标记聚合器示例。
*/
function Cluster(markerClusterer){
this._markerClusterer = markerClusterer;
this._map = markerClusterer.getMap();
this._minClusterSize = markerClusterer.getMinClusterSize();
this._isAverageCenter = markerClusterer.isAverageCenter();
this._center = null;//落脚位置
this._markers = [];//这个Cluster中所包含的markers
this._gridBounds = null;//以中心点为准，向四边扩大gridSize个像素的范围，也即网格范围
this._isReal = false; //真的是个聚合
this._clusterMarker = new BMapLib.TextIconOverlay(this._center, this._markers.length, {"styles":this._markerClusterer.getStyles()});
//this._map.addOverlay(this._clusterMarker);
}
/**
* 向该聚合添加一个标记。
* @param {Marker} marker 要添加的标记。
* @return 无返回值。
*/
Cluster.prototype.addMarker = function(marker){
if(this.isMarkerInCluster(marker)){
return false;
}//也可用marker.isInCluster判断,外面判断OK，这里基本不会命中
if (!this._center){
this._center = marker.getPosition();
this.updateGridBounds();//
} else {
if(this._isAverageCenter){
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 BMap.Point(lng, lat);
this.updateGridBounds();
}//计算新的Center
}
marker.isInCluster = true;
this._markers.push(marker);
var len = this._markers.length;
if(len < this._minClusterSize ){
this._map.addOverlay(marker);
//this.updateClusterMarker();
return true;
} else if (len === this._minClusterSize) {
for (var i = 0; i < len; i++) {
this._markers[i].getMap() && this._map.removeOverlay(this._markers[i]);
}
}
this._map.addOverlay(this._clusterMarker);
this._isReal = true;
this.updateClusterMarker();
return true;
};
/**
* 判断一个标记是否在该聚合中。
* @param {Marker} marker 要判断的标记。
* @return {Boolean} true或false。
*/
Cluster.prototype.isMarkerInCluster= 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;
};
/**
* 判断一个标记是否在该聚合网格范围中。
* @param {Marker} marker 要判断的标记。
* @return {Boolean} true或false。
*/
Cluster.prototype.isMarkerInClusterBounds = function(marker) {
return this._gridBounds.containsPoint(marker.getPosition());
};
Cluster.prototype.isReal = function(marker) {
return this._isReal;
};
/**
* 更新该聚合的网格范围。
* @return 无返回值。
*/
Cluster.prototype.updateGridBounds = function() {
var bounds = new BMap.Bounds(this._center, this._center);
this._gridBounds = getExtendedBounds(this._map, bounds, this._markerClusterer.getGridSize());
};
/**
* 更新该聚合的显示样式，也即TextIconOverlay。
* @return 无返回值。
*/
Cluster.prototype.updateClusterMarker = function () {
if (this._map.getZoom() > this._markerClusterer.getMaxZoom()) {
this._clusterMarker && this._map.removeOverlay(this._clusterMarker);
for (var i = 0, marker; marker = this._markers[i]; i++) {
this._map.addOverlay(marker);
}
return;
}
if (this._markers.length < this._minClusterSize) {
this._clusterMarker.hide();
return;
}
this._clusterMarker.setPosition(this._center);
this._clusterMarker.setText(this._markers.length);
var thatMap = this._map;
var thatBounds = this.getBounds();
this._clusterMarker.addEventListener("click", function(event){
thatMap.setViewport(thatBounds);
});
};
/**
* 删除该聚合。
* @return 无返回值。
*/
Cluster.prototype.remove = function(){
for (var i = 0, m; m = this._markers[i]; i++) {
this._markers[i].getMap() && this._map.removeOverlay(this._markers[i]);
}//清除散的标记点
this._map.removeOverlay(this._clusterMarker);
this._markers.length = 0;
delete this._markers;
}
/**
* 获取该聚合所包含的所有标记的最小外接矩形的范围。
* @return {BMap.Bounds} 计算出的范围。
*/
Cluster.prototype.getBounds = function() {
var bounds = new BMap.Bounds(this._center,this._center);
for (var i = 0, marker; marker = this._markers[i]; i++) {
bounds.extend(marker.getPosition());
}
return bounds;
};
/**
* 获取该聚合的落脚点。
* @return {BMap.Point} 该聚合的落脚点。
*/
Cluster.prototype.getCenter = function() {
return this._center;
};
})();
这经过测试发现_addToClosestCluster耗时最严重，进一步跟踪到这里，发现是addMarker太占资源了：
跟踪到 Cluster.prototype.addMarker 找到 updateClusterMarker 这个方法
进入 Cluster.prototype.updateClusterMarker 在下图的位置加一个return; 发现效率提供了几百倍，只是地图上再也没有热点了，因为return 屏蔽了下面的绘制。
仔细看了一下这个函数发现这里有个比较严重的问题，如果有5000个点，那么就会调用5000次的addMarker，也就会执行5000次的 setPosition和 setText，这样当然会慢了。应该是在 Cluster数据准备好了一次性绘制到MAP上，例如有10个聚合也只需要绘制10次而已。
于是我加一个聚合的绘制方法：
我同时屏蔽了click事件，因为发现 setViewport 会触发多次的zoomend和moveend，导致聚合被_redraw了很多次！
Cluster.prototype.drawToMap = function(){
this._clusterMarker.setPosition(this._center);
this._clusterMarker.setText(this._markers.length);
return;
var thatMap = this._map;
var thatBounds = this.getBounds();
this._clusterMarker.addEventListener("click", function(event){
thatMap.setViewport(thatBounds); //bug! 这里多次出发 moveend _redraw
});
}
这个在 MarkerClusterer.prototype._createClusters 最后循环调用一次即可：
MarkerClusterer.prototype._createClusters = function(){
log(‘_createClusters begin..‘);
var mapBounds = this._map.getBounds();
var extendedBounds = getExtendedBounds(this._map, mapBounds, this._gridSize);
for(var i = 0, marker; marker = this._markers[i]; i++){
//marker 不属于任何聚合 && marker 在map视图范围内
if(!marker.isInCluster && extendedBounds.containsPoint(marker.getPosition()) ){
this._addToClosestCluster(marker);
}
}
log(‘_createClusters end..‘);
for(var i = 0, cluster; cluster = this._clusters[i]; i++){
cluster.drawToMap(); //一起绘制到地图上
}
};
修改后有个小BUG，需要同时修改下TextIconOverlay脚本，在TextIconOverlay.prototype._updateCss里加一个判断：
/**
*更新相应的CSS。
*@return 无返回值。
*/
TextIconOverlay.prototype._updateCss = function(){
var style = this.getStyleByText(this._text, this._styles);
if(this._domElement){
this._domElement.style.cssText = this._buildCssText(style);
}
};
经过修改后的MarkerClusterer效率提高了不少，5000个坐标下运行还是比较流畅的，到了3w个坐标还是有点吃力。
1.8w数据
1W数据
修改后的 MarkerClusterer.js
var BMapLib = window.BMapLib = BMapLib || {};
(function() {
var getExtendedBounds = function(map, bounds, gridSize) {
bounds = cutBoundsInRange(bounds);
var pixelNE = map.pointToPixel(bounds.getNorthEast());
var pixelSW = map.pointToPixel(bounds.getSouthWest());
pixelNE.x += gridSize;
pixelNE.y -= gridSize;
pixelSW.x -= gridSize;
pixelSW.y += gridSize;
var newNE = map.pixelToPoint(pixelNE);
var newSW = map.pixelToPoint(pixelSW);
return new BMap.Bounds(newSW, newNE)
};
var cutBoundsInRange = function(bounds) {
var maxX = getRange(bounds.getNorthEast().lng, -180, 180);
var minX = getRange(bounds.getSouthWest().lng, -180, 180);
var maxY = getRange(bounds.getNorthEast().lat, -74, 74);
var minY = getRange(bounds.getSouthWest().lat, -74, 74);
return new BMap.Bounds(new BMap.Point(minX, minY), new BMap.Point(maxX, maxY))
};
var getRange = function(i, mix, max) {
mix && (i = Math.max(i, mix));
max && (i = Math.min(i, max));
return i
};
var isArray = function(source) {
return ‘[object Array]‘ === Object.prototype.toString.call(source)
};
var indexOf = function(item, source) {
var index = -1;
if (isArray(source)) {
if (source.indexOf) {
index = source.indexOf(item)
} else {
for (var i = 0, m; m = source[i]; i++) {
if (m === item) {
index = i;
break
}
}
}
}
return index
};
var MarkerClusterer = BMapLib.MarkerClusterer = function(map, options) {
if (!map) {
return
}
this._map = map;
this._markers = [];
this._clusters = [];
var opts = options || {};
this._gridSize = opts["gridSize"] || 60;
this._maxZoom = opts["maxZoom"] || 18;
this._minClusterSize = opts["minClusterSize"] || 2;
this._isAverageCenter = false;
if (opts[‘isAverageCenter‘] != undefined) {
this._isAverageCenter = opts[‘isAverageCenter‘]
}
this._styles = opts["styles"] || [];
var that = this;
this._map.addEventListener("zoomend", function() {
that._redraw()
});
this._map.addEventListener("moveend", function() {
that._redraw()
});
var mkrs = opts["markers"];
isArray(mkrs) && this.addMarkers(mkrs)
};
MarkerClusterer.prototype.addMarkers = function(markers) {
for (var i = 0, len = markers.length; i < len; i++) {
this._pushMarkerTo(markers[i])
}
this._createClusters()
};
MarkerClusterer.prototype._pushMarkerTo = function(marker) {
var index = indexOf(marker, this._markers);
if (index === -1) {
marker.isInCluster = false;
this._markers.push(marker)
}
};
MarkerClusterer.prototype.addMarker = function(marker) {
this._pushMarkerTo(marker);
this._createClusters()
};
MarkerClusterer.prototype._createClusters = function() {
var mapBounds = this._map.getBounds();
var extendedBounds = getExtendedBounds(this._map, mapBounds, this._gridSize);
for (var i = 0, marker; marker = this._markers[i]; i++) {
if (!marker.isInCluster && extendedBounds.containsPoint(marker.getPosition())) {
this._addToClosestCluster(marker)
}
}
for (var i = 0, cluster; cluster = this._clusters[i]; i++) {
cluster.drawToMap()
}
};
MarkerClusterer.prototype._addToClosestCluster = function(marker) {
var distance = 4000000;
var clusterToAddTo = null;
var position = marker.getPosition();
for (var i = 0, cluster; cluster = this._clusters[i]; i++) {
var center = cluster.getCenter();
if (center) {
var d = this._map.getDistance(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)
}
};
MarkerClusterer.prototype._clearLastClusters = function() {
for (var i = 0, cluster; cluster = this._clusters[i]; i++) {
cluster.remove()
}
this._clusters = [];
this._removeMarkersFromCluster()
};
MarkerClusterer.prototype._removeMarkersFromCluster = function() {
for (var i = 0, marker; marker = this._markers[i]; i++) {
marker.isInCluster = false
}
};
MarkerClusterer.prototype._removeMarkersFromMap = function() {
for (var i = 0, marker; marker = this._markers[i]; i++) {
marker.isInCluster = false;
this._map.removeOverlay(marker)
}
};
MarkerClusterer.prototype._removeMarker = function(marker) {
var index = indexOf(marker, this._markers);
if (index === -1) {
return false
}
this._map.removeOverlay(marker);
this._markers.splice(index, 1);
return true
};
MarkerClusterer.prototype.removeMarker = function(marker) {
var success = this._removeMarker(marker);
if (success) {
this._clearLastClusters();
this._createClusters()
}
return success
};
MarkerClusterer.prototype.removeMarkers = function(markers) {
var success = false;
for (var i = 0; i < markers.length; i++) {
var r = this._removeMarker(markers[i]);
success = success || r
}
if (success) {
this._clearLastClusters();
this._createClusters()
}
return success
};
MarkerClusterer.prototype.clearMarkers = function() {
this._clearLastClusters();
this._removeMarkersFromMap();
this._markers = []
};
MarkerClusterer.prototype._redraw = function() {
this._clearLastClusters();
this._createClusters()
};
MarkerClusterer.prototype.getGridSize = function() {
return this._gridSize
};
MarkerClusterer.prototype.setGridSize = function(size) {
this._gridSize = size;
this._redraw()
};
MarkerClusterer.prototype.getMaxZoom = function() {
return this._maxZoom
};
MarkerClusterer.prototype.setMaxZoom = function(maxZoom) {
this._maxZoom = maxZoom;
this._redraw()
};
MarkerClusterer.prototype.getStyles = function() {
return this._styles
};
MarkerClusterer.prototype.setStyles = function(styles) {
this._styles = styles;
this._redraw()
};
MarkerClusterer.prototype.getMinClusterSize = function() {
return this._minClusterSize
};
MarkerClusterer.prototype.setMinClusterSize = function(size) {
this._minClusterSize = size;
this._redraw()
};
MarkerClusterer.prototype.isAverageCenter = function() {
return this._isAverageCenter
};
MarkerClusterer.prototype.getMap = function() {
return this._map
};
MarkerClusterer.prototype.getMarkers = function() {
return this._markers
};
MarkerClusterer.prototype.getClustersCount = function() {
var count = 0;
for (var i = 0, cluster; cluster = this._clusters[i]; i++) {
cluster.isReal() && count++
}
return count
};
function Cluster(markerClusterer) {
this._markerClusterer = markerClusterer;
this._map = markerClusterer.getMap();
this._minClusterSize = markerClusterer.getMinClusterSize();
this._isAverageCenter = markerClusterer.isAverageCenter();
this._center = null;
this._markers = [];
this._gridBounds = null;
this._isReal = false;
this._clusterMarker = new BMapLib.TextIconOverlay(this._center, this._markers.length, {
"styles": this._markerClusterer.getStyles()
})
}
Cluster.prototype.addMarker = function(marker) {
if (this.isMarkerInCluster(marker)) {
return false
}
if (!this._center) {
this._center = marker.getPosition();
this.updateGridBounds()
} else {
if (this._isAverageCenter) {
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 BMap.Point(lng, lat);
this.updateGridBounds()
}
}
marker.isInCluster = true;
this._markers.push(marker);
var len = this._markers.length;
if (len < this._minClusterSize) {
this._map.addOverlay(marker);
return true
} else if (len === this._minClusterSize) {
for (var i = 0; i < len; i++) {
this._markers[i].getMap() && this._map.removeOverlay(this._markers[i])
}
}
this._map.addOverlay(this._clusterMarker);
this._isReal = true;
this.updateClusterMarker();
return true
};
Cluster.prototype.isMarkerInCluster = 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
};
Cluster.prototype.isMarkerInClusterBounds = function(marker) {
return this._gridBounds.containsPoint(marker.getPosition())
};
Cluster.prototype.isReal = function(marker) {
return this._isReal
};
Cluster.prototype.updateGridBounds = function() {
var bounds = new BMap.Bounds(this._center, this._center);
this._gridBounds = getExtendedBounds(this._map, bounds, this._markerClusterer.getGridSize())
};
Cluster.prototype.drawToMap = function() {
this._clusterMarker.setPosition(this._center);
this._clusterMarker.setText(this._markers.length);
return;
var thatMap = this._map;
var thatBounds = this.getBounds();
this._clusterMarker.addEventListener("click", function(event) {
thatMap.setViewport(thatBounds)
})
}
Cluster.prototype.updateClusterMarker = function() {
if (this._map.getZoom() > this._markerClusterer.getMaxZoom()) {
this._clusterMarker && this._map.removeOverlay(this._clusterMarker);
for (var i = 0, marker; marker = this._markers[i]; i++) {
this._map.addOverlay(marker)
}
return
}
if (this._markers.length < this._minClusterSize) {
this._clusterMarker.hide();
return
}
return;
this._clusterMarker.setPosition(this._center);
this._clusterMarker.setText(this._markers.length);
var thatMap = this._map;
var thatBounds = this.getBounds();
this._clusterMarker.addEventListener("click", function(event) {
thatMap.setViewport(thatBounds)
})
};
Cluster.prototype.remove = function() {
for (var i = 0, m; m = this._markers[i]; i++) {
this._markers[i].getMap() && this._map.removeOverlay(this._markers[i])
}
this._map.removeOverlay(this._clusterMarker);
this._markers.length = 0;
delete this._markers
}
Cluster.prototype.getBounds = function() {
var bounds = new BMap.Bounds(this._center, this._center);
for (var i = 0, marker; marker = this._markers[i]; i++) {
bounds.extend(marker.getPosition())
}
return bounds
};
Cluster.prototype.getCenter = function() {
return this._center
}
})();
时间： 2024-10-16 00:47:27