interior-point

Compute an interior point (representative point) of any GeoJSON geometry.

Ported from the JTS Topology Suite InteriorPoint algorithm. GeoJSON-native, zero runtime dependencies.

Installation

npm install interior-point

Usage

import { interiorPoint } from "interior-point";

const polygon = {
  type: "Polygon",
  coordinates: [
    [
      [0, 0],
      [6, 0],
      [6, 2],
      [2, 2],
      [2, 8],
      [0, 8],
      [0, 0],
    ],
  ],
};

const point = interiorPoint(polygon);
console.log(point);
// => [1, 5]

API

interiorPoint(geometry: Geometry | null): Position | null

Returns a [x, y] position guaranteed to lie inside the geometry (for polygons) or on the geometry (for lines/points). Returns null for empty geometries.

Supported geometry types:

• Polygon, MultiPolygon — scanline interior point
• LineString, MultiLineString — vertex nearest to centroid
• Point, MultiPoint — point nearest to centroid
• GeometryCollection — uses highest-dimension non-empty component

License

MIT

This library contains algorithms ported from JTS (EPL 2.0 / EDL 1.0).