Clustering
This sample demonstrates how to enable point clustering on a GeoJSONLayer. Clustering is a method of reducing points in a FeatureLayer, CSVLayer, GeoJSONLayer, WFSLayer, or OGCFeatureLayer by grouping them based on their spatial proximity to one another. Typically, clusters are proportionally sized based on the number of features within each cluster.
GeoBlazor
dymaptic
About this sample
This GeoBlazor Pro sample, written in Blazor for .NET developers, demonstrates point clustering on a GeoJSONLayer from the ArcGIS Maps SDK for JavaScript exposed through GeoBlazor's GeoJSONLayer and FeatureReductionCluster Razor components. The page shows a polar 2D map (Alaska Polar Stereographic projection) of the world rendered in dark gray, displaying earthquake points from the USGS feed for the last month. Nearby earthquakes are reduced into light-blue circular clusters labeled with the count of events they represent, and individual quakes appear as triangles when zoomed in. A HomeWidget pinned in the upper-left corner returns to the starting extent, and an adjacent ExpandWidget opens a panel with an Enable/Disable Clustering toggle button and a LegendWidget. Clicking the toggle calls SetFeatureReduction to switch between aggregated clusters and raw points. The sample is intended to demonstrate spatial clustering of streamed GeoJSON data with custom cluster sizing and labeling.