/supercluster

A crazy fast geospatial point clustering library for browsers and Node.

Primary LanguageJavaScriptISC LicenseISC

supercluster Simply Awesome Build Status

A very fast JavaScript library for geospatial point clustering for browsers and Node.

<script src="https://unpkg.com/supercluster@2.3.0/dist/supercluster.min.js"></script>
var index = supercluster({
    radius: 40,
    maxZoom: 16
});
index.load(points);
index.getClusters([-180, -85, 180, 85], 2);

Clustering 6 million points in Leaflet:

clusters2

Methods

load(points)

Loads an array of GeoJSON.Feature objects. Each feature's geometry must be a GeoJSON.Point. Once loaded, index is immutable.

getClusters(bbox, zoom)

For the given bbox array ([westLng, southLat, eastLng, northLat]) and integer zoom, returns an array of clusters and points as GeoJSON.Feature objects.

getTile(z, x, y)

For a given zoom and x/y coordinates, returns a geojson-vt-compatible JSON tile object with cluster/point features.

getChildren(clusterId, clusterZoom)

Returns the children of a cluster (on the next zoom level) given its id (cluster_id value from feature properties) and zoom the cluster was from.

getLeaves(clusterId, clusterZoom, limit = 10, offset = 0)

Returns all the points of a cluster (given its cluster_id and zoom), with pagination support: limit is the number of points to return (set to Infinity for all points), and offset is the amount of points to skip (for pagination).

getClusterExpansionZoom(clusterId, clusterZoom)

Returns the zoom on which the cluster expands into several children (useful for "click to zoom" feature), given the cluster's cluster_id and zoom.

Options

Option Default Description
minZoom 0 Minimum zoom level at which clusters are generated.
maxZoom 16 Maximum zoom level at which clusters are generated.
radius 40 Cluster radius, in pixels.
extent 512 (Tiles) Tile extent. Radius is calculated relative to this value.
nodeSize 64 Size of the KD-tree leaf node. Affects performance.
log false Whether timing info should be logged.

Developing Supercluster

npm install       # install dependencies
npm run build-dev # generate dist/supercluster.js
npm run build-min # generate dist/supercluster.min.js
npm test          # run tests