# @cgcs2000/supercluster

> A very fast geospatial point clustering library.

Latest version **7.1.3** (published 2021-05-27) · ISC license · 0 weekly downloads

## Install

```sh
npm install @cgcs2000/supercluster
pnpm add @cgcs2000/supercluster
yarn add @cgcs2000/supercluster
bun add @cgcs2000/supercluster
```

## Health

**Score 20/100 (F)** — status: abandoned.

Positive: esm support; no vulnerabilities.

Warnings: low downloads; no types.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 7.1.3 |
| Published | 2021-05-27 |
| First published | 2019-01-18 |
| Weekly downloads | 0 |
| License | ISC |
| TypeScript types | none |
| Module format | ESM + CommonJS |
| Dependencies | 1 |
| Unpacked size | 46.4 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 0 |
| Author | Vladimir Agafonkin |
| Maintainers | jingsam, wanyanyan |
| Keywords | clustering, geospatial, markers |

## Links

- npm: https://www.npmjs.com/package/@cgcs2000/supercluster
- Repository: https://github.com/cgcs2000/supercluster
- npm.io page: https://npm.io/package/@cgcs2000/supercluster

## Dependencies (1)

- [kdbush](https://npm.io/package/kdbush.md) ^3.0.0

## Recent versions

- 7.1.3 (latest) — 2021-05-27
- 7.1.2 — 2021-02-19
- 7.1.1 — 2021-02-19
- 7.1.0 — 2020-06-03
- 7.0.0 — 2019-11-07
- 6.0.2 — 2019-07-24
- 6.0.1 — 2019-02-13
- 6.0.0 — 2019-01-18

## README

# supercluster [![Simply Awesome](https://img.shields.io/badge/simply-awesome-brightgreen.svg)](https://github.com/mourner/projects) [![Build Status](https://travis-ci.org/cgcs2000/supercluster.svg?branch=cgcs2000)](https://travis-ci.org/cgcs2000/supercluster)

> This repository is a fork of `mapbox/supercluster`, but for CGCS2000 projection.

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

```html
<script src="https://unpkg.com/supercluster@7.1.2/dist/supercluster.min.js"></script>
```

```js
const index = new Supercluster({
    radius: 40,
    maxZoom: 16
});
index.load(points);
index.getClusters([-180, -85, 180, 85], 2);
```

Clustering 6 million points in Leaflet:

![clusters2](https://cloud.githubusercontent.com/assets/25395/11857351/43407b46-a40c-11e5-8662-e99ab1cd2cb7.gif)

## Install

Install using NPM (`npm install supercluster`) or Yarn (`yarn add supercluster`), then:

```js
// import as a ES module
import Supercluster from 'supercluster';

// or require in Node / Browserify
const Supercluster = require('supercluster');
```

Or use a browser build directly:

```html
<script src="https://unpkg.com/supercluster@7.1.2/dist/supercluster.min.js"></script>
```

## Methods

#### `load(points)`

Loads an array of [GeoJSON Feature](https://tools.ietf.org/html/rfc7946#section-3.2) objects. Each feature's `geometry` must be a [GeoJSON Point](https://tools.ietf.org/html/rfc7946#section-3.1.2). 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](https://tools.ietf.org/html/rfc7946#section-3.2) objects.

#### `getTile(z, x, y)`

For a given zoom and x/y coordinates, returns a [geojson-vt](https://github.com/mapbox/geojson-vt)-compatible JSON tile object with cluster/point features.

#### `getChildren(clusterId)`

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

#### `getLeaves(clusterId, limit = 10, offset = 0)`

Returns all the points of a cluster (given its `cluster_id`), 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)`

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     | Default | Description                                                       |
|------------|---------|-------------------------------------------------------------------|
| minZoom    | 0       | Minimum zoom level at which clusters are generated.               |
| maxZoom    | 16      | Maximum zoom level at which clusters are generated.               |
| minPoints  | 2       | Minimum number of points to form a cluster.                       |
| 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.                             |
| generateId | false   | Whether to generate ids for input features in vector tiles.       |

### Property map/reduce options

In addition to the options above, supercluster supports property aggregation with the following two options:

- `map`: a function that returns cluster properties corresponding to a single point.
- `reduce`: a reduce function that merges properties of two clusters into one.

Example of setting up a `sum` cluster property that accumulates the sum of `myValue` property values:

```js
const index = new Supercluster({
    map: (props) => ({sum: props.myValue}),
    reduce: (accumulated, props) => { accumulated.sum += props.sum; }
});
```

Note that `reduce` must not mutate the second argument (`props`).

## Developing Supercluster

```
npm install       # install dependencies
npm run build     # generate dist/supercluster.js and dist/supercluster.min.js
npm test          # run tests
```

---
_Source: https://npm.io/package/@cgcs2000/supercluster · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._