ArcGIS实现聚合点效果

function queryfunc(){map.graphics.clear();if(clusterLayer!=undefined){map.removeLayer(clusterLayer);}$.ajax({url:'gis/tt',data:{month:$('#search_date').val(),city:$('#cityName').combobox('getValue')},success : function(data) {obj= $.parseJSON(data);if(obj.length<1){alert("当前条件下未查询到数据");return false;} require(["dojo/_base/array","esri/Color","esri/map","esri/layers/ArcGISTiledMapServiceLayer","esri/request","esri/graphic","esri/geometry/Extent","esri/symbols/SimpleMarkerSymbol","esri/symbols/PictureMarkerSymbol","esri/symbols/SimpleLineSymbol","esri/symbols/SimpleFillSymbol","esri/renderers/ClassBreaksRenderer","esri/layers/GraphicsLayer","esri/SpatialReference","esri/geometry/Point","esri/geometry/webMercatorUtils","ClusterLayer","dojo/domReady!"      ], function (arrayUtils,                Color,                Map,                ArcGISTiledMapServiceLayer,                esriRequest,                Graphic,                Extent,                SimpleMarkerSymbol,                PictureMarkerSymbol,                SimpleLineSymbol,                SimpleFillSymbol,                ClassBreaksRenderer,                GraphicsLayer,                SpatialReference,                Point,                webMercatorUtils,                ClusterLayer){ var countyInfo = {}; var multipoint = new esri.geometry.Multipoint(); var resultUnionExtent;             countyInfo.data = arrayUtils.map(obj, function(item) {                 var latlng = new  Point(item.LONGITUDE, item.LATITUDE, map.spatialReference);                 multipoint.addPoint(new  Point(item.LONGITUDE, item.LATITUDE));                   var webMercator = webMercatorUtils.geographicToWebMercator(latlng);                 var attributes = {                   /*   "小区名称": item.cell_name, */                     "经度": item.LONGITUDE,                     "纬度": item.LATITUDE,                 };                 return {                     "x": webMercator.x,                     "y": webMercator.y,                     "attributes": attributes                 };         });         clusterLayer = new ClusterLayer({                "data": countyInfo.data,                "distance": 100,                "labelColor": "#fff",                "labelOffset": 10,                "resolution": map.extent.getWidth() / map.width,                "singleColor": "#888"            });            var defaultSym = new SimpleMarkerSymbol().setSize(4);            var renderer = new ClassBreaksRenderer(defaultSym, "clusterCount");            var picBaseUrl = "${basePath}app/templates/manage/wyproblemcell/images/";            var marker = new PictureMarkerSymbol("${basePath}app/templates/manage/arcgis319/img/marker.png",44,33);            var blue = new PictureMarkerSymbol(picBaseUrl + "BluePin1LargeB.png", 32, 32).setOffset(0, 15);            var green = new PictureMarkerSymbol(picBaseUrl + "GreenPin1LargeB.png", 64, 64).setOffset(0, 15);            var red = new PictureMarkerSymbol(picBaseUrl + "RedPin1LargeB.png", 72, 72).setOffset(0, 15);            renderer.addBreak(0, 2, marker);            renderer.addBreak(2, 500, green);            renderer.addBreak(500, 20001, red);            clusterLayer.setRenderer(renderer);            map.addLayer(clusterLayer);            if(multipoint.points.length > 0){    if(resultUnionExtent == null){    resultUnionExtent = multipoint.getExtent();    }else{    resultUnionExtent = resultUnionExtent.union(multipoint.getExtent());    } } map.setExtent(resultUnionExtent.expand(1.2));  }); }});}