jsts

What is jsts?

The jsts (JavaScript Topology Suite) npm package is a JavaScript library for performing various geometric operations. It is a port of the well-known JTS Topology Suite, which is widely used in the GIS (Geographic Information Systems) community. The library provides a range of functionalities for creating, manipulating, and analyzing planar geometric objects.

What are jsts's main functionalities?

Geometry Creation

This feature allows you to create geometric objects from Well-Known Text (WKT) representations. In this example, a point geometry is created from a WKT string.

const jsts = require('jsts');
const reader = new jsts.io.WKTReader();
const point = reader.read('POINT (10 20)');
console.log(point);

Geometric Operations

This feature allows you to perform geometric operations such as union, intersection, and difference. In this example, the union operation is performed on two polygon geometries.

const jsts = require('jsts');
const reader = new jsts.io.WKTReader();
const geom1 = reader.read('POLYGON ((30 10, 40 40, 20 40, 10 20, 30 10))');
const geom2 = reader.read('POLYGON ((20 30, 35 35, 30 20, 20 30))');
const union = geom1.union(geom2);
console.log(union);

Spatial Analysis

This feature allows you to perform spatial analysis operations such as calculating distances between geometries. In this example, the distance between two point geometries is calculated.

const jsts = require('jsts');
const reader = new jsts.io.WKTReader();
const geom1 = reader.read('POINT (10 20)');
const geom2 = reader.read('POINT (30 40)');
const distance = geom1.distance(geom2);
console.log(distance);

Other packages similar to jsts

turf

Turf is a JavaScript library for advanced geospatial analysis. It provides a wide range of spatial operations and is highly optimized for performance. Compared to jsts, Turf offers more functionalities for working with GeoJSON data and is often used in web mapping applications.

geolib

Geolib is a lightweight library for geospatial operations in JavaScript. It focuses on basic geospatial calculations such as distance, area, and bounding boxes. While it is not as feature-rich as jsts, it is simpler to use for basic geospatial tasks.

openlayers

OpenLayers is a powerful library for displaying and interacting with maps in web applications. It includes some geospatial analysis functionalities but is primarily focused on map rendering and user interaction. Compared to jsts, OpenLayers is more suitable for building interactive map applications.

README

JSTS Topology Suite

The JSTS Topology Suite is a JavaScript library of spatial predicates and functions for processing geometry conforming to the Simple Features Specification for SQL published by the Open Geospatial Consortium. JSTS Topology Suite is also a JavaScript port of the well established Java library JTS Topology Suite with a built in parser for OpenLayers geometries.

SWECO Position AB (my current employer) has gratiously provided sponsoring for this project.

The primary goal of the project is to provide OpenLayers applications with a complete library for processing and analysing simple geometries, but as of version 0.11.0 hard dependencies to OpenLayers was removed which makes it possible to use JSTS Topology Suite as a free standing geometry library.

A Google group is available for developer discussions.

Unit tests are made using the Jasmine testing framework. A port of JTS Validation Suite provides additional tests.

A recent trunk snapshot of API docs is available. Also available are simple example use of buffer, overlay and triangulation operations. The examples uses a build of attache-array-js to meet JavaScript ES5 requirements in some browsers.

The code tries to be conformant to the Google JavaScript Style Guide and JSLint and is licensed with the LGPL 2.1 license.

Development environment

• Eclipse 4.3.1 (Kepler)
• Assumes OpenLayers 2.13.1 distribution in project root from http://www.openlayers.org/
• Assumes OS Ubuntu/Linux

Design changes

These are effective/potential changes from the original JTS Topology Suite:

• Skip abstracted CoordinateSequence interface/implementation

JSTS in use

• Viper - a game that uses quadtree index and the robust line intersection algorithm.