@turf/difference

difference

Finds the difference between multiple polygons by clipping the subsequent polygon from the first.

Parameters

• features FeatureCollection<(Polygon | MultiPolygon)> input Polygon features

Examples

var polygon1 = turf.polygon([[
  [128, -26],
  [141, -26],
  [141, -21],
  [128, -21],
  [128, -26]
]], {
  "fill": "#F00",
  "fill-opacity": 0.1
});
var polygon2 = turf.polygon([[
  [126, -28],
  [140, -28],
  [140, -20],
  [126, -20],
  [126, -28]
]], {
  "fill": "#00F",
  "fill-opacity": 0.1
});

var difference = turf.difference(turf.featureCollection([polygon1, polygon2]));

//addToMap
var addToMap = [polygon1, polygon2, difference];

Returns (Feature<(Polygon | MultiPolygon)> | null) a Polygon or MultiPolygon feature showing the area of polygon1 excluding the area of polygon2 (if empty returns null)

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/difference

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

$ npm install @turf/turf