@turf/kinks

What is @turf/kinks?

@turf/kinks is a module in the Turf.js library that is used to detect self-intersections (kinks) in GeoJSON polygons. This is useful for validating and cleaning up spatial data to ensure that polygons are well-formed and do not contain any self-intersecting lines.

What are @turf/kinks's main functionalities?

Detecting Kinks in Polygons

This feature allows you to detect self-intersections in a given GeoJSON polygon. The code sample creates a polygon with a self-intersection and uses the `turf.kinks` function to find and log the kinks.

const turf = require('@turf/turf');
const polygon = turf.polygon([[
  [-12.034835, 8.901183],
  [-12.060413, 8.899826],
  [-12.03638, 8.873199],
  [-12.034835, 8.901183]
]]);
const kinks = turf.kinks(polygon);
console.log(kinks);

Other packages similar to @turf/kinks

jsts

JSTS (JavaScript Topology Suite) is a JavaScript library of spatial predicates and functions for processing geometry. It provides more comprehensive geometry operations compared to @turf/kinks, including robust algorithms for intersection, union, and difference operations.

martinez-polygon-clipping

Martinez Polygon Clipping is a library for performing boolean operations on polygons, such as union, intersection, and difference. While it does not specifically focus on detecting kinks, it can be used to handle complex polygon operations and ensure valid geometries.

README

@turf/kinks

kinks

Takes a linestring, multi-linestring, multi-polygon, or polygon and returns points at all self-intersections.

Parameters

• featureIn Feature<(LineString | MultiLineString | MultiPolygon | Polygon)> input feature

Examples

var poly = turf.polygon([[
  [-12.034835, 8.901183],
  [-12.060413, 8.899826],
  [-12.03638, 8.873199],
  [-12.059383, 8.871418],
  [-12.034835, 8.901183]
]]);

var kinks = turf.kinks(poly);

//addToMap
var addToMap = [poly, kinks]

Returns FeatureCollection<Point> self-intersections

---

This module is part of the Turfjs project, an open source module collection dedicated to geographic algorithms. It is maintained in the Turfjs/turf repository, where you can create PRs and issues.

Installation

Install this module individually:

$ npm install @turf/kinks

Or install the Turf module that includes it as a function:

$ npm install @turf/turf

Changelog

6.4.0

🏅 New Features/Enhancements

• @turf/boolean-point-on-line Added an epislon option to help in floating point comparison. (PR https://github.com/Turfjs/turf/pull/2051 - Author @okcoker)

🐛 Bug Fixes

• @turf/line-slice-along Fixed a bug where the offset distance equal to the length of the line (PR https://github.com/Turfjs/turf/pull/2030 - Author @EricPKerr)

• @turf/helpers Fixed the conversion ratio for converting meters to yards and vice-versa (PR https://github.com/Turfjs/turf/pull/2046 - Author @anotherhale)

• @turf/center-median Fixed a missing TS type import (PR https://github.com/Turfjs/turf/pull/2044 - Author @Seairth)

• `@turf/bezier-spline Fix a bug ensuring the spline result reaches the end of the input (PR https://github.com/Turfjs/turf/pull/2090 - Author @the-nemz)

📖 Documentation

• @turf/transform-rotate and @turf/ellipse) Improve documentation for angle parameter (PR https://github.com/Turfjs/turf/pull/2016 - Author @pasieronen)

• @turf/line-chunk Fix an invalid anchor (PR https://github.com/Turfjs/turf/pull/2071 - Author @GraxMonzo)

• @turf/distance Enhance distance doco so supported inputs are clearer (PR https://github.com/Turfjs/turf/pull/2032 - Author @rowanwins)

🔔 Misc

• @turf/concave Replace deprecated topojson dependency (PR https://github.com/Turfjs/turf/pull/2037 - Author @elliots)

• Work towards enabling TS Strict Mode (PR https://github.com/Turfjs/turf/pull/2053 - Author @mfedderly)