Supercluster

A very fast Rust crate for geospatial point clustering.

This crate is inspired by Mapbox's supercluster blog post.

Reference implementation

Features

• load(points): Loads a FeatureCollection Object. Each feature should be a Feature Object.

• get_clusters(bbox, zoom): For the given bbox array ([west_lng, south_lat, east_lng, north_lat]) and zoom, returns an array of clusters and points as Feature Object objects.

• get_tile(z, x, y): For a given zoom and x/y coordinates, returns a FeatureCollection Object.

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

• get_leaves(cluster_id, limit, offset): Returns all the points of a cluster (given its cluster_id), with pagination support.

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

Options

Option	Description
min_zoom	Minimum zoom level at which clusters are generated.
max_zoom	Maximum zoom level at which clusters are generated.
min_points	Minimum number of points to form a cluster.
radius	Cluster radius, in pixels.
extent	(Tiles) Tile extent. Radius is calculated relative to this value.
node_size	Size of the KD-tree leaf node. Affects performance.

Safety

This crate uses #![forbid(unsafe_code)] to ensure everything is implemented in 100% safe Rust.

Documentation

For more in-depth details, please refer to the full documentation.

If you encounter any issues or have questions that are not addressed in the documentation, feel free to submit an issue.

Usage

Run the following Cargo command in your project directory:

cargo add supercluster

use geojson::FeatureCollection;
use supercluster::{ Supercluster, Options };

fn main() {
  let options = Options {
      max_zoom: 16,
      min_zoom: 0,
      min_points: 2,
      radius: 40.0,
      node_size: 64,
      extent: 512.0,
  };

  // Create a new instance with the specified configuration settings
  let mut cluster = Supercluster::new(options);

  // Load a FeatureCollection Object into the Supercluster instance

  // [GeoJSON Format Specification § 5](https://tools.ietf.org/html/rfc7946#section-5)
  let feature_collection = FeatureCollection {
    bbox: None,
    // [GeoJSON Format Specification § 3.2](https://datatracker.ietf.org/doc/html/rfc7946#section-3.2)
    features: vec![],
    foreign_members: None,
  };
  let index = cluster.load(feature_collection);

  // Retrieve a FeatureCollection Object within a tile at the given zoom level and tile coordinates
  let tile = index.get_tile(0, 0.0, 0.0).expect("cannot get a tile");

  ...
}

Contributing

Build:

cargo build

Test:

cargo test

Run clippy:

cargo clippy --all-targets --all-features --no-deps -- -D warnings

Run rustfmt:

cargo fmt

Generate documentation in HTML format:

cargo doc --open

Sponsors