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Clusters appear when the map is zoomed out far enough that locations points are too small and close together to be able to easily select. A cluster will show up as a numbered square on the map (pictured below). The number signifies the number of locations points that are part of the cluster. For clusters that include 5 or more locations points a “5+” will display.
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The clustering functionality mainly follows this algorithm: https://developers.google.com/maps/documentation/javascript/marker-clustering
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On selection:
When a cluster is clicked, the map will zoom to the point where the individual locations of the cluster are shown. into the cluster where:
The zoom in will be close enough where the cluster icon is no longer necessary and the individual points can be selected.
The cluster will break up into clusters (Ex. a cluster of 4 will break into two clusters of 2 once zoomed in). These clusters can then be selected to zoom in further.
If the map reaches the maximum zoom level and
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points are still overlapping, then the cluster icons will not show and the pop-up interaction (shown above) will take place
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Zooming In & Out:
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.