Clusterer=function(map)
{this.map=map;this.markers=[];
 this.clusters=[];
 this.timeout=null;
 this.currentZoomLevel=map.getZoom();
 this.maxVisibleMarkers=Clusterer.defaultMaxVisibleMarkers;
 this.gridSize=Clusterer.defaultGridSize;
 this.minMarkersPerCluster=Clusterer.defaultMinMarkersPerCluster;
 this.maxLinesPerInfoBox=Clusterer.defaultMaxLinesPerInfoBox;
 this.icon=Clusterer.defaultIcon;
 GEvent.addListener(map,'zoomend',Clusterer.MakeCaller(Clusterer.Display,this));
 GEvent.addListener(map,'moveend',Clusterer.MakeCaller(Clusterer.Display,this));
 GEvent.addListener(map,'infowindowclose',Clusterer.MakeCaller(Clusterer.PopDown,this));
};

Clusterer.defaultMaxVisibleMarkers=150;
Clusterer.defaultGridSize=5;
Clusterer.defaultMinMarkersPerCluster=5;
Clusterer.defaultMaxLinesPerInfoBox=10;
Clusterer.defaultIcon=new GIcon();
Clusterer.defaultIcon.image='http://www.acme.com/resources/images/markers/blue_large.PNG';
Clusterer.defaultIcon.shadow='http://www.acme.com/resources/images/markers/shadow_large.PNG';
Clusterer.defaultIcon.iconSize=new GSize(30,51);
Clusterer.defaultIcon.shadowSize=new GSize(56,51);
Clusterer.defaultIcon.iconAnchor=new GPoint(13,34);
Clusterer.defaultIcon.infoWindowAnchor=new GPoint(13,3);
Clusterer.defaultIcon.infoShadowAnchor=new GPoint(27,37);
Clusterer.prototype.SetIcon=function(icon) { 
    this.icon=icon;
  };
Clusterer.prototype.SetMaxVisibleMarkers=function(n) { 
    this.maxVisibleMarkers=n;
  };
Clusterer.prototype.SetMinMarkersPerCluster=function(n) { 
    this.minMarkersPerCluster=n;
  };
Clusterer.prototype.SetMaxLinesPerInfoBox=function(n) { 
    this.maxLinesPerInfoBox=n;
  };
Clusterer.prototype.AddMarker=function(marker,title) {
  if(marker.setMap!=null)
    marker.setMap(this.map);
    marker.title=title;
    marker.onMap=false;
    this.markers.push(marker);
    this.DisplayLater();
};
Clusterer.prototype.RemoveMarker=function(marker) {
  for(var i=0;i<this.markers.length;++i)
    if(this.markers[i]==marker) {
      if(marker.onMap)
        this.map.removeOverlay(marker);
        for(var j=0;j<this.clusters.length;++j) {
          var cluster=this.clusters[j];
          if(cluster!=null) {
            for(var k=0;k<cluster.markers.length;++k)
              if(cluster.markers[k]==marker) {
                cluster.markers[k]=null;
                --cluster.markerCount;
                break;
              }
              if(cluster.markerCount==0) {
                this.ClearCluster(cluster);
                this.clusters[j]=null;
              } else if(cluster==this.poppedUpCluster)
                Clusterer.RePop(this);
          }
        }
        this.markers[i]=null;break;
    }
    this.DisplayLater();
};
Clusterer.prototype.DisplayLater=function() {
  if(this.timeout!=null)
    clearTimeout(this.timeout);
    this.timeout=setTimeout(Clusterer.MakeCaller(Clusterer.Display,this),50);
};
Clusterer.Display=function(clusterer) {
  var i,j,marker,cluster;
  clearTimeout(clusterer.timeout);
  var newZoomLevel=clusterer.map.getZoom();
  if(newZoomLevel!=clusterer.currentZoomLevel) {
    for(i=0;i<clusterer.clusters.length;++i)
      if(clusterer.clusters[i]!=null) {
        clusterer.ClearCluster(clusterer.clusters[i]);
        clusterer.clusters[i]=null;
      }
    clusterer.clusters.length=0;
    clusterer.currentZoomLevel=newZoomLevel;
  }
  var bounds=clusterer.map.getBounds();
  var sw=bounds.getSouthWest();
  var ne=bounds.getNorthEast();
  var dx=ne.lng()-sw.lng();
  var dy=ne.lat()-sw.lat();
  if(dx<300&&dy<150) {
    dx*=0.10;dy*=0.10;
    bounds=new GLatLngBounds(new GLatLng(sw.lat()-dy,sw.lng()-dx),new GLatLng(ne.lat()+dy,ne.lng()+dx));
  }
  var visibleMarkers=[];
  var nonvisibleMarkers=[];
  for(i=0;i<clusterer.markers.length;++i) {
    marker=clusterer.markers[i];
    if(marker!=null)
      if(bounds.contains(marker.getPoint())) {
        visibleMarkers.push(marker);
      } else {
        nonvisibleMarkers.push(marker);
      }
  }
  for(i=0;i<nonvisibleMarkers.length;++i) {
    marker=nonvisibleMarkers[i];
    if(marker.onMap) {
      clusterer.map.removeOverlay(marker);
      marker.onMap=false;
    }
  }
  for(i=0;i<clusterer.clusters.length;++i) {
    cluster=clusterer.clusters[i];
    if(cluster!=null&&!bounds.contains(cluster.marker.getPoint())&&cluster.onMap) {
      clusterer.map.removeOverlay(cluster.marker);
      cluster.onMap=false;
    }
  }
  if(visibleMarkers.length>clusterer.maxVisibleMarkers) {
    var latRange=bounds.getNorthEast().lat()-bounds.getSouthWest().lat();
    var latInc=latRange/clusterer.gridSize;
    var lngInc=latInc/Math.cos((bounds.getNorthEast().lat()+bounds.getSouthWest().lat())/2.0*Math.PI/180.0);
    for(var lat=bounds.getSouthWest().lat();lat<=bounds.getNorthEast().lat();lat+=latInc)
      for(var lng=bounds.getSouthWest().lng();lng<=bounds.getNorthEast().lng();lng+=lngInc) {
        cluster=new Object();
        cluster.clusterer=clusterer;
        cluster.bounds=new GLatLngBounds(new GLatLng(lat,lng),new GLatLng(lat+latInc,lng+lngInc));
        cluster.markers=[];
        cluster.markerCount=0;
        cluster.onMap=false;
        cluster.marker=null;
        clusterer.clusters.push(cluster);
      }
      for(i=0;i<visibleMarkers.length;++i) {
        marker=visibleMarkers[i];
        if(marker!=null&&!marker.inCluster) {
          for(j=0;j<clusterer.clusters.length;++j) {
            cluster=clusterer.clusters[j];
            if(cluster!=null&&cluster.bounds.contains(marker.getPoint())) {
              cluster.markers.push(marker);
              ++cluster.markerCount;
              marker.inCluster=true;
            }
          }
        }
      }
      for(i=0;i<clusterer.clusters.length;++i)
        if(clusterer.clusters[i]!=null&&clusterer.clusters[i].markerCount<clusterer.minMarkersPerCluster) {
          clusterer.ClearCluster(clusterer.clusters[i]);
          clusterer.clusters[i]=null;
        }
      for(i=clusterer.clusters.length-1;i>=0;--i)
        if(clusterer.clusters[i]!=null)
          break;
        else
          --clusterer.clusters.length;
          for(i=0;i<clusterer.clusters.length;++i) {
            cluster=clusterer.clusters[i];
            if(cluster!=null) {
              for(j=0;j<cluster.markers.length;++j) {
                marker=cluster.markers[j];
                if(marker!=null&&marker.onMap) {
                  clusterer.map.removeOverlay(marker);
                  marker.onMap=false;
                }
              }
            }
          }
          for(i=0;i<clusterer.clusters.length;++i) {
            cluster=clusterer.clusters[i];
            if(cluster!=null&&cluster.marker==null) {
              var xTotal=0.0,yTotal=0.0;
              for(j=0;j<cluster.markers.length;++j) {
                marker=cluster.markers[j];
                if(marker!=null) {
                  xTotal+=(+marker.getPoint().lng());
                  yTotal+=(+marker.getPoint().lat());
                }
              }
              var location=new GLatLng(yTotal/cluster.markerCount,xTotal/cluster.markerCount);
              marker=new GMarker(location,{icon:clusterer.icon});
              cluster.marker=marker;
              GEvent.addListener(marker,'click',Clusterer.MakeCaller(Clusterer.PopUp,cluster));
            }
         }
  }
  for(i=0;i<visibleMarkers.length;++i) {
    marker=visibleMarkers[i];
    if(marker!=null&&!marker.onMap&&!marker.inCluster) {
      clusterer.map.addOverlay(marker);
      if(marker.addedToMap!=null) marker.addedToMap();
      marker.onMap=true;
    }
  }
  for(i=0;i<clusterer.clusters.length;++i) {
    cluster=clusterer.clusters[i];
    if(cluster!=null&&!cluster.onMap&&bounds.contains(cluster.marker.getPoint())) {
      clusterer.map.addOverlay(cluster.marker);
      cluster.onMap=true;
    }
  }
  Clusterer.RePop(clusterer);
};

Clusterer.PopUp=function(cluster) {
  var clusterer=cluster.clusterer;
  var html='<table width="300">';
  var n=0;
  for(var i=0;i<cluster.markers.length;++i) {
    var marker=cluster.markers[i];
    if(marker!=null) {
      ++n;
      html+='<tr><td>';
      if(marker.getIcon().smallImage!=null) 
        html+='<img src="'+marker.getIcon().smallImage+'">';
      else
        html+='<img src="'+marker.getIcon().image+'" width="'+(marker.getIcon().iconSize.width/2)+'" height="'+(marker.getIcon().iconSize.height/2)+'">';
        html+='</td><td>'+marker.title+'</td></tr>';
      if(n==clusterer.maxLinesPerInfoBox-1&&cluster.markerCount>clusterer.maxLinesPerInfoBox) {
        html+='<tr><td colspan="2">...and '+(cluster.markerCount-n)+' more</td></tr>';
        break;
      }
    }
  }
  html+='</table>';
  clusterer.map.closeInfoWindow();
  cluster.marker.openInfoWindowHtml(html);
  clusterer.poppedUpCluster=cluster;
};

Clusterer.RePop=function(clusterer) {
  if(clusterer.poppedUpCluster!=null)
    Clusterer.PopUp(clusterer.poppedUpCluster);
};

Clusterer.PopDown=function(clusterer) {
  clusterer.poppedUpCluster=null;
};

Clusterer.prototype.ClearCluster=function(cluster) {
  var i,marker;
  for(i=0;i<cluster.markers.length;++i)
    if(cluster.markers[i]!=null) {
      cluster.markers[i].inCluster=false;
      cluster.markers[i]=null;
    }
  cluster.markers.length=0;
  cluster.markerCount=0;
  if(cluster==this.poppedUpCluster)
    this.map.closeInfoWindow();
    if(cluster.onMap) {
      this.map.removeOverlay(cluster.marker);
      cluster.onMap=false;
    }
};

Clusterer.MakeCaller=function(func,arg) {
  return function(){
    func(arg);
  };
};

GMarker.prototype.setMap=function(map) {
  this.map=map;
};

GMarker.prototype.addedToMap=function() {
  this.map=null;
};

GMarker.prototype.origOpenInfoWindow=GMarker.prototype.openInfoWindow;

GMarker.prototype.openInfoWindow=function(node,opts) {
  if(this.map!=null)
    return this.map.openInfoWindow(this.getPoint(),node,opts);
  else
    return this.origOpenInfoWindow(node,opts);
};

GMarker.prototype.origOpenInfoWindowHtml=GMarker.prototype.openInfoWindowHtml;

GMarker.prototype.openInfoWindowHtml=function(html,opts) {
  if(this.map!=null)
    return this.map.openInfoWindowHtml(this.getPoint(),html,opts);
  else
    return this.origOpenInfoWindowHtml(html,opts);
};

GMarker.prototype.origOpenInfoWindowTabs=GMarker.prototype.openInfoWindowTabs;

GMarker.prototype.openInfoWindowTabs=function(tabNodes,opts) {
  if(this.map!=null)
    return this.map.openInfoWindowTabs(this.getPoint(),tabNodes,opts);
  else
    return this.origOpenInfoWindowTabs(tabNodes,opts);
};

GMarker.prototype.origOpenInfoWindowTabsHtml=GMarker.prototype.openInfoWindowTabsHtml;

GMarker.prototype.openInfoWindowTabsHtml=function(tabHtmls,opts) {
  if(this.map!=null)
    return this.map.openInfoWindowTabsHtml(this.getPoint(),tabHtmls,opts);
  else
    return this.origOpenInfoWindowTabsHtml(tabHtmls,opts);
};

GMarker.prototype.origShowMapBlowup=GMarker.prototype.showMapBlowup;

GMarker.prototype.showMapBlowup=function(opts) {
  if(this.map!=null)
    return this.map.showMapBlowup(this.getPoint(),opts);
  else
    return this.origShowMapBlowup(opts);
};