callumacrae / kdbush

A fast static index for 2D points

KDBush

A very fast static spatial index for 2D points based on a flat KD-tree. Compared to RBush:

• points only — no rectangles
• static — you can't add/remove items
• indexing is 5-8 times faster

const index = new KDBush(points);         // make an index
const ids1 = index.range(10, 10, 20, 20); // bbox search - minX, minY, maxX, maxY
const ids2 = index.within(10, 10, 5);     // radius search - x, y, radius

Install

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

// import as a ES module
import KDBush from 'kdbush';

// or require in Node / Browserify
const KDBush = require('kdbush');

Or use a browser build directly:

<script src="https://unpkg.com/[email protected]/kdbush.min.js"></script>

API

new KDBush(points[, getX, getY, nodeSize, arrayType])

Creates an index from the given points.

• points: Input array of points.
• getX, getY: Functions to get x and y from an input point. By default, it assumes [x, y] format.
• nodeSize: Size of the KD-tree node, 64 by default. Higher means faster indexing but slower search, and vise versa.
• arrayType: Array type to use for storing coordinate values. Float64Array by default, but if your coordinates are integer values, Int32Array makes things a bit faster.

const index = new KDBush(points, p => p.x, p => p.y, 64, Int32Array);

index.range(minX, minY, maxX, maxY)

Finds all items within the given bounding box and returns an array of indices that refer to the items in the original points input array.

const results = index.range(10, 10, 20, 20).map(id => points[id]);

index.within(x, y, radius)

Finds all items within a given radius from the query point and returns an array of indices.

const results = index.within(10, 10, 5).map(id => points[id]);