Hi Pat

    Could you tell us what class are you using to plot the points from your JSON feed ? I'm assuming this is an ObjectLayer in the explanation below.

    Your requirement can be achieved by adding a ClusterLayer and an ObjectLayer to your map, then using a button to switch between the two. To act as the datasource for your ClusterLayer you can write your own IPointFeatureSource class that uses the JSON feed as a source for clustering data. This could even potentially be integrated into your existing Web Service. The button would then effectively toggle between point data and clusters.

    It would be worth modifying the ASP.NET program that produces clusters for our JS Clustering demo script to get your IPointFeatureSource working. This can be found in the files tutorial.clustering.ashx in your Scripts folder.

    You can directly email us at gbsupport@telogis.com if you need to share code or has further queries on this topic.


    We developed a totally client side clustering routine that we use with Geostream. We have our core database and data server on a Linux environment and we were passing vehicle data points that we were using in graphs, listings and pois on the map. Anyway we some clustering routines that would allow us to create our own cluster poi point which has the vehicle count. So we don't have a clustering layer, we simply have single point pois and clustered pois.

    We then added a declutter on click which would pinwheel out the individual icons from the cluster (think we maxed it to 30, clusters bigger we popped a balloon stating to zoom in more). This allowed us to link our clusters to the data lists that we show, to highlight rows and interact between map pois, listings and even the chart components - all client side javascript.

    We had our doubts about the speed when we started but we actually found our cluster routine handled the clustering and setting the poi on the map even faster than the map/satellite tiles load in sometimes.

    We have some work on making it more general and object oriented for broader use - but you may find it useful.

    Feel free to e-mail me and I can get you more detail and possibly a demonstration of it.

    Chuck Durham