a5-to-geojson

A lightweight utility library for converting A5 cells to GeoJSON features and geometries, along with additional tools for working with the A5 geoindexing system.

Features

• Convert A5 cells to GeoJSON Point and Polygon features or geometries.
• Convert coordinates to A5 cells and vice versa.
• Calculate the bounding box (BBox) of an A5 cell.
• Get the resolution of an A5 cell.

Installation

Install the library:

npm install a5-to-geojson

or

pnpm add a5-to-geojson

Usage

Here is an example of how to use the library:

import {
  coordToA5,
  a5ToCoord,
  a5ToPointFeature,
  a5ToPolygonFeature,
} from 'a5-to-geojson';

// Convert coordinates to an A5 cell
const coord = [-3.6886, 40.4201]; // Madrid [longitude, latitude]
const resolution = 9;
const a5Cell = coordToA5(coord, resolution);
console.log('A5 Cell:', a5Cell);

// Convert an A5 cell back to coordinates
const backToCoord = a5ToCoord(a5Cell);
console.log('Coordinates:', backToCoord);

// Convert an A5 cell to a GeoJSON Point feature
const pointFeature = a5ToPointFeature(a5Cell);
console.log('GeoJSON Point Feature:', pointFeature);

// Convert an A5 cell to a GeoJSON Polygon feature
const polygonFeature = a5ToPolygonFeature(a5Cell);
console.log('GeoJSON Polygon Feature:', polygonFeature);

Documentation

See DOCS

License

This project is licensed under the MIT License.

Acknowledgements

• Built on top of the a5-js library.
• GeoJSON utilities powered by @turf/helpers.
• Made by Alberto Rico