Finds the difference between multiple polygons by clipping the subsequent polygon from the first.
-
features
FeatureCollection<(Polygon | MultiPolygon)> input Polygon features
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.
Install this single module individually:
$ npm install @turf/difference
Or install the all-encompassing @turf/turf module that includes all modules as functions:
$ npm install @turf/turf