OpenLayers, nice marker clustering

Question

Do you know how to have a nice clustering in OpenLayers such as this google example ?

Answer 1

Here is the JSfiddle for clustering based on custom attributes added to the layers. I struggled a bit with this so putting it here; Also shows creating a summary pie graph image when zoomed out with the clustered data http://jsfiddle.net/alexcpn/518p59k4/

Also created a small openlayer tutorial to explain this OpenLayers Advanced Clustering

    var getClusterCount = function (feature) {

    var clustercount = {};
    var planningcount = 0;
    var onaircount = 0;
    var inerrorcount = 0;

    for (var i = 0; i < feature.cluster.length; i++) {

        if (feature.cluster[i].attributes.cluster) {
        //THE MOST IMPORTANT LINE IS THE ONE BELOW, While clustering open layers removes the orginial feature layer with its own. So to get the attributes of the feature you have added add it to the openlayer created feature layer
            feature.attributes.cluster = feature.cluster[i].attributes.cluster;
            switch (feature.cluster[i].attributes.cluster) {

 ......
    return clustercount;
};