百度点聚合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。
http://api.map.baidu.com/library/MarkerClusterer/1.2/docs/symbols/BMapLib.MarkerClusterer.html
最基本的实现（在此两个按钮的功能没有实现）：
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
<style type="text/css">
body, html { 100%;height: 100%;margin:0;font-family:"微软雅黑";}
#allmap{100%;height:80%;}
#r-result{100%;}
</style>
<script type="text/javascript" src="http://api.map.baidu.com/api?v=2.0&ak=您的密钥"></script>
<script type="text/javascript" src="http://api.map.baidu.com/library/TextIconOverlay/1.2/src/TextIconOverlay_min.js"></script>
<script type="text/javascript" src="http://api.map.baidu.com/library/MarkerClusterer/1.2/src/MarkerClusterer_min.js"></script>
<title>点聚合</title>
</head>
<body>
<div id="allmap"></div>
<div id="r-result">
<input type="button" onclick="add_overlay();" value="添加点聚合" />
<input type="button" onclick="remove_overlay();" value="重新生成点聚合" />
</div>
</body>
</html>
<script type="text/javascript">
// 百度地图API功能
var map = new BMap.Map("allmap");
map.centerAndZoom(new BMap.Point(116.404, 39.915), 4);
map.enableScrollWheelZoom();
var MAX = 10;
var markers = [];
var markerClusterer = null;
for (var i = 0; i < MAX; i++) {
var pt = new BMap.Point(Math.random()*40+85, Math.random()*30+21);
var marker = new BMap.Marker(pt);
map.addOverlay(marker);
markers.push(marker);
}
//最简单的用法，生成一个marker数组，然后调用markerClusterer类即可。
markerClusterer = new BMapLib.MarkerClusterer(map, {markers:markers});
</script>
实现两个按钮的功能，用于添加点聚合，和删除点聚合并重新加载新的点
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
<style type="text/css">
body, html { 100%;height: 100%;margin:0;font-family:"微软雅黑";}
#allmap{100%;height:80%;}
#r-result{100%;}
</style>
<script type="text/javascript" src="http://api.map.baidu.com/api?v=2.0&ak=您的密钥"></script>
<script type="text/javascript" src="http://api.map.baidu.com/library/TextIconOverlay/1.2/src/TextIconOverlay_min.js"></script>
<script type="text/javascript" src="http://api.map.baidu.com/library/MarkerClusterer/1.2/src/MarkerClusterer_min.js"></script>
<title>点聚合</title>
</head>
<body>
<div id="allmap"></div>
<div id="r-result">
<input type="button" onclick="add_overlay();" value="添加点聚合" />
<input type="button" onclick="remove_overlay();" value="重新生成点聚合" />
</div>
</body>
</html>
<script type="text/javascript">
// 百度地图API功能
var map = new BMap.Map("allmap");
map.centerAndZoom(new BMap.Point(116.404, 39.915), 4);
map.enableScrollWheelZoom();
var MAX = 10;
var markers = [];
var markerClusterer = null;
for (var i = 0; i < MAX; i++) {
var pt = new BMap.Point(Math.random()*40+85, Math.random()*30+21);
var marker = new BMap.Marker(pt);
map.addOverlay(marker);
markers.push(marker);
}
function add_overlay(){
//最简单的用法，生成一个marker数组，然后调用markerClusterer类即可。
markerClusterer = new BMapLib.MarkerClusterer(map, {markers:markers});
}
function remove_overlay(){
for(var i=0; i<4; i++){
map.removeOverlay(markers[i]);
}
var markers1 = markers.slice(4,markers.length);
markerClusterer.clearMarkers(); //此步骤需要
markerClusterer = new BMapLib.MarkerClusterer(map, {markers:markers1});
}
</script>
