kali ini saya akan share turorial cara menggunakan marker cluster di gmaps, fungsi dari marker cluster sendiri adalah untuk mengelompokan marker / pointer yang jarak latitude dan longitude nya saling berdekatan antara suatu marker dengan marker yang lainnya.
marker cluster sangat perlu di gunakan jika jumlah marker yang akan di tampilkan di peta sudah membludak, karena dengan menggunakan marker cluster marker satu dengan marker yang lainnya tidak akan bertumpuk atau tumpang tindih, dan menggunakan marker cluster juga tampilan marker pada peta akan lebih enak di lihat di bandingkan dengan yang tidak menggunakan marker cluster
ok dari pada berlama lama kita langsung saja ke inti pembahasan, pertama buatlah projek dengan nama terserah anda lalu salin kode berikut dan simpan file dengan nama markerclusterer_compiled.js

(function(){var d=null;function e(a){return function(b){this[a]=b}}function h(a){return function(){return this[a]}}var j;
function k(a,b,c){this.extend(k,google.maps.OverlayView);this.c=a;this.a=[];this.f=[];this.ca=[53,56,66,78,90];this.j=[];this.A=!1;c=c||{};this.g=c.gridSize||60;this.l=c.minimumClusterSize||2;this.J=c.maxZoom||d;this.j=c.styles||[];this.X=c.imagePath||this.Q;this.W=c.imageExtension||this.P;this.O=!0;if(c.zoomOnClick!=void 0)this.O=c.zoomOnClick;this.r=!1;if(c.averageCenter!=void 0)this.r=c.averageCenter;l(this);this.setMap(a);this.K=this.c.getZoom();var f=this;google.maps.event.addListener(this.c,
"zoom_changed",function(){var a=f.c.getZoom();if(f.K!=a)f.K=a,f.m()});google.maps.event.addListener(this.c,"idle",function(){f.i()});b&&b.length&&this.C(b,!1)}j=k.prototype;j.Q="http://google-maps-utility-library-v3.googlecode.com/svn/trunk/markerclusterer/images/m";j.P="png";j.extend=function(a,b){return function(a){for(var b in a.prototype)this.prototype[b]=a.prototype[b];return this}.apply(a,[b])};j.onAdd=function(){if(!this.A)this.A=!0,n(this)};j.draw=function(){};
function l(a){if(!a.j.length)for(var b=0,c;c=a.ca[b];b++)a.j.push({url:a.X+(b+1)+"."+a.W,height:c,width:c})}j.S=function(){for(var a=this.o(),b=new google.maps.LatLngBounds,c=0,f;f=a[c];c++)b.extend(f.getPosition());this.c.fitBounds(b)};j.z=h("j");j.o=h("a");j.V=function(){return this.a.length};j.ba=e("J");j.I=h("J");j.G=function(a,b){for(var c=0,f=a.length,g=f;g!==0;)g=parseInt(g/10,10),c++;c=Math.min(c,b);return{text:f,index:c}};j.$=e("G");j.H=h("G");
j.C=function(a,b){for(var c=0,f;f=a[c];c++)q(this,f);b||this.i()};function q(a,b){b.s=!1;b.draggable&&google.maps.event.addListener(b,"dragend",function(){b.s=!1;a.L()});a.a.push(b)}j.q=function(a,b){q(this,a);b||this.i()};function r(a,b){var c=-1;if(a.a.indexOf)c=a.a.indexOf(b);else for(var f=0,g;g=a.a[f];f++)if(g==b){c=f;break}if(c==-1)return!1;b.setMap(d);a.a.splice(c,1);return!0}j.Y=function(a,b){var c=r(this,a);return!b&&c?(this.m(),this.i(),!0):!1};
j.Z=function(a,b){for(var c=!1,f=0,g;g=a[f];f++)g=r(this,g),c=c||g;if(!b&&c)return this.m(),this.i(),!0};j.U=function(){return this.f.length};j.getMap=h("c");j.setMap=e("c");j.w=h("g");j.aa=e("g");
j.v=function(a){var b=this.getProjection(),c=new google.maps.LatLng(a.getNorthEast().lat(),a.getNorthEast().lng()),f=new google.maps.LatLng(a.getSouthWest().lat(),a.getSouthWest().lng()),c=b.fromLatLngToDivPixel(c);c.x+=this.g;c.y-=this.g;f=b.fromLatLngToDivPixel(f);f.x-=this.g;f.y+=this.g;c=b.fromDivPixelToLatLng(c);b=b.fromDivPixelToLatLng(f);a.extend(c);a.extend(b);return a};j.R=function(){this.m(!0);this.a=[]};
j.m=function(a){for(var b=0,c;c=this.f[b];b++)c.remove();for(b=0;c=this.a[b];b++)c.s=!1,a&&c.setMap(d);this.f=[]};j.L=function(){var a=this.f.slice();this.f.length=0;this.m();this.i();window.setTimeout(function(){for(var b=0,c;c=a[b];b++)c.remove()},0)};j.i=function(){n(this)};
function n(a){if(a.A)for(var b=a.v(new google.maps.LatLngBounds(a.c.getBounds().getSouthWest(),a.c.getBounds().getNorthEast())),c=0,f;f=a.a[c];c++)if(!f.s&&b.contains(f.getPosition())){for(var g=a,u=4E4,o=d,v=0,m=void 0;m=g.f[v];v++){var i=m.getCenter();if(i){var p=f.getPosition();if(!i||!p)i=0;else var w=(p.lat()-i.lat())*Math.PI/180,x=(p.lng()-i.lng())*Math.PI/180,i=Math.sin(w/2)*Math.sin(w/2)+Math.cos(i.lat()*Math.PI/180)*Math.cos(p.lat()*Math.PI/180)*Math.sin(x/2)*Math.sin(x/2),i=6371*2*Math.atan2(Math.sqrt(i),
Math.sqrt(1-i));i<u&&(u=i,o=m)}}o&&o.F.contains(f.getPosition())?o.q(f):(m=new s(g),m.q(f),g.f.push(m))}}function s(a){this.k=a;this.c=a.getMap();this.g=a.w();this.l=a.l;this.r=a.r;this.d=d;this.a=[];this.F=d;this.n=new t(this,a.z(),a.w())}j=s.prototype;
j.q=function(a){var b;a:if(this.a.indexOf)b=this.a.indexOf(a)!=-1;else{b=0;for(var c;c=this.a[b];b++)if(c==a){b=!0;break a}b=!1}if(b)return!1;if(this.d){if(this.r)c=this.a.length+1,b=(this.d.lat()*(c-1)+a.getPosition().lat())/c,c=(this.d.lng()*(c-1)+a.getPosition().lng())/c,this.d=new google.maps.LatLng(b,c),y(this)}else this.d=a.getPosition(),y(this);a.s=!0;this.a.push(a);b=this.a.length;b<this.l&&a.getMap()!=this.c&&a.setMap(this.c);if(b==this.l)for(c=0;c<b;c++)this.a[c].setMap(d);b>=this.l&&a.setMap(d);
a=this.c.getZoom();if((b=this.k.I())&&a>b)for(a=0;b=this.a[a];a++)b.setMap(this.c);else if(this.a.length<this.l)z(this.n);else{b=this.k.H()(this.a,this.k.z().length);this.n.setCenter(this.d);a=this.n;a.B=b;a.ga=b.text;a.ea=b.index;if(a.b)a.b.innerHTML=b.text;b=Math.max(0,a.B.index-1);b=Math.min(a.j.length-1,b);b=a.j[b];a.da=b.url;a.h=b.height;a.p=b.width;a.M=b.textColor;a.e=b.anchor;a.N=b.textSize;a.D=b.backgroundPosition;this.n.show()}return!0};
j.getBounds=function(){for(var a=new google.maps.LatLngBounds(this.d,this.d),b=this.o(),c=0,f;f=b[c];c++)a.extend(f.getPosition());return a};j.remove=function(){this.n.remove();this.a.length=0;delete this.a};j.T=function(){return this.a.length};j.o=h("a");j.getCenter=h("d");function y(a){a.F=a.k.v(new google.maps.LatLngBounds(a.d,a.d))}j.getMap=h("c");
function t(a,b,c){a.k.extend(t,google.maps.OverlayView);this.j=b;this.fa=c||0;this.u=a;this.d=d;this.c=a.getMap();this.B=this.b=d;this.t=!1;this.setMap(this.c)}j=t.prototype;
j.onAdd=function(){this.b=document.createElement("DIV");if(this.t)this.b.style.cssText=A(this,B(this,this.d)),this.b.innerHTML=this.B.text;this.getPanes().overlayMouseTarget.appendChild(this.b);var a=this;google.maps.event.addDomListener(this.b,"click",function(){var b=a.u.k;google.maps.event.trigger(b,"clusterclick",a.u);b.O&&a.c.fitBounds(a.u.getBounds())})};function B(a,b){var c=a.getProjection().fromLatLngToDivPixel(b);c.x-=parseInt(a.p/2,10);c.y-=parseInt(a.h/2,10);return c}
j.draw=function(){if(this.t){var a=B(this,this.d);this.b.style.top=a.y+"px";this.b.style.left=a.x+"px"}};function z(a){if(a.b)a.b.style.display="none";a.t=!1}j.show=function(){if(this.b)this.b.style.cssText=A(this,B(this,this.d)),this.b.style.display="";this.t=!0};j.remove=function(){this.setMap(d)};j.onRemove=function(){if(this.b&&this.b.parentNode)z(this),this.b.parentNode.removeChild(this.b),this.b=d};j.setCenter=e("d");
function A(a,b){var c=[];c.push("background-image:url("+a.da+");");c.push("background-position:"+(a.D?a.D:"0 0")+";");typeof a.e==="object"?(typeof a.e[0]==="number"&&a.e[0]>0&&a.e[0]<a.h?c.push("height:"+(a.h-a.e[0])+"px; padding-top:"+a.e[0]+"px;"):c.push("height:"+a.h+"px; line-height:"+a.h+"px;"),typeof a.e[1]==="number"&&a.e[1]>0&&a.e[1]<a.p?c.push("width:"+(a.p-a.e[1])+"px; padding-left:"+a.e[1]+"px;"):c.push("width:"+a.p+"px; text-align:center;")):c.push("height:"+a.h+"px; line-height:"+a.h+
"px; width:"+a.p+"px; text-align:center;");c.push("cursor:pointer; top:"+b.y+"px; left:"+b.x+"px; color:"+(a.M?a.M:"black")+"; position:absolute; font-size:"+(a.N?a.N:11)+"px; font-family:Arial,sans-serif; font-weight:bold");return c.join("")}window.MarkerClusterer=k;k.prototype.addMarker=k.prototype.q;k.prototype.addMarkers=k.prototype.C;k.prototype.clearMarkers=k.prototype.R;k.prototype.fitMapToMarkers=k.prototype.S;k.prototype.getCalculator=k.prototype.H;k.prototype.getGridSize=k.prototype.w;
k.prototype.getExtendedBounds=k.prototype.v;k.prototype.getMap=k.prototype.getMap;k.prototype.getMarkers=k.prototype.o;k.prototype.getMaxZoom=k.prototype.I;k.prototype.getStyles=k.prototype.z;k.prototype.getTotalClusters=k.prototype.U;k.prototype.getTotalMarkers=k.prototype.V;k.prototype.redraw=k.prototype.i;k.prototype.removeMarker=k.prototype.Y;k.prototype.removeMarkers=k.prototype.Z;k.prototype.resetViewport=k.prototype.m;k.prototype.repaint=k.prototype.L;k.prototype.setCalculator=k.prototype.$;
k.prototype.setGridSize=k.prototype.aa;k.prototype.setMaxZoom=k.prototype.ba;k.prototype.onAdd=k.prototype.onAdd;k.prototype.draw=k.prototype.draw;s.prototype.getCenter=s.prototype.getCenter;s.prototype.getSize=s.prototype.T;s.prototype.getMarkers=s.prototype.o;t.prototype.onAdd=t.prototype.onAdd;t.prototype.draw=t.prototype.draw;t.prototype.onRemove=t.prototype.onRemove;
})();

selanjutnya buat file dengan nama index.php kemudian salin kode di bawah ini

<!DOCTYPE html>
<html>
<head>
<title>MEMBUAT MARKER CLUSTER</title>
<script type="text/javascript" src="http://maps.google.com/maps/api/js"></script>
<script type="text/javascript" src="markerclusterer_compiled.js"></script>
<script type="text/javascript">
 window.onload = function() {
  // set info window
  var infowindow = new google.maps.InfoWindow();

  // set position
  var pos = new google.maps.LatLng(-3.050444,116.323242);

  // set option untuk peta
  var option = {
   center: pos,
   zoom: 4,
   mapTypeId:google.maps.MapTypeId.ROADMAP
  };

  // set peta
  var map = new google.maps.Map(document.getElementById('maps'), option);
  infowindow = new google.maps.InfoWindow({
   content: 'loading...'
  });

  // set lokasi 
  var lokasi = [
   [1, 'Marker 1', -6.28096974938, 106.97618132000002, 'Ini marker 1'],
   [2, 'Marker 2', -6.1353311, 106.77639049999993, 'Ini marker 2'],
   [3, 'Marker 3', -6.284479, 107.132158, 'Ini marker 3'],
   [4, 'Marker 4', -7.644871999999999, 112.90329700000007, 'Ini marker 4'],
   [5, 'Marker 5', -6.9277375, 107.56980859999999, 'Ini marker 5'],
   [6, 'Marker 6', 0.4976277, 101.39423220000003, 'Ini marker 6'],
   [7, 'Marker 7', -6.222443200000001, 106.7334588, 'Ini marker 7'],
   [8, 'Marker 8', -7.289166000000001, 112.73439800000006, 'Ini marker 8'],
   [9, 'Marker 9', -6.156798999999999, 106.61758699999996, 'Ini marker 9'],
   [10, 'Marker 10', -7.981894, 112.62650299999996, 'Ini marker 10']
  ];

  // set bounds
  var bounds = new google.maps.LatLngBounds();
  var markers = [];

  // loop lokasi and push to markers
  for (var i = 0; i < lokasi.length; i++) {
   var pos = new google.maps.LatLng(lokasi[i][2], lokasi[i][3]);
   var marker = new google.maps.Marker({
    position: pos,
    map: map,
    title: lokasi[i][1],
    zIndex: lokasi[i][0],
    html: lokasi[i][4]
   });
   bounds.extend(pos);
   google.maps.event.addListener(marker, 'click', function () {
    infowindow.setContent('<b>'+ this.title +'</b><br/>'+ this.html);
    infowindow.open(map, this);
   });
   markers.push(marker);
  }
  map.fitBounds(bounds);

  // set marker cluster
  var markerCluster = new MarkerClusterer(map, markers);

 }
</script>
</head>
<body>
<div id="maps" style="width: 600px; height: 400px; background-color: #EEE"></div>
</body>
</html>

anda juga bisa merubah isi dari varibale lokasi berdasarkan data dari database anda.
Ok, sampai disini dulu turorial kali ini, selamat mencoba dan semoga bisa bermanfaat