@turf/inside

turf-inside

inside

Takes a Point and a Polygon or MultiPolygon and determines if the point resides inside the polygon. The polygon can be convex or concave. The function accounts for holes.

Parameters

• point Feature<Point> input point
• polygon Feature<(Polygon | MultiPolygon)> input polygon or multipolygon

Examples

var pt1 = {
  "type": "Feature",
  "properties": {
    "marker-color": "#f00"
  },
  "geometry": {
    "type": "Point",
    "coordinates": [-111.467285, 40.75766]
  }
};
var pt2 = {
  "type": "Feature",
  "properties": {
    "marker-color": "#0f0"
  },
  "geometry": {
    "type": "Point",
    "coordinates": [-111.873779, 40.647303]
  }
};
var poly = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Polygon",
    "coordinates": [[
      [-112.074279, 40.52215],
      [-112.074279, 40.853293],
      [-111.610107, 40.853293],
      [-111.610107, 40.52215],
      [-112.074279, 40.52215]
    ]]
  }
};

var features = {
  "type": "FeatureCollection",
  "features": [pt1, pt2, poly]
};

//=features

var isInside1 = turf.inside(pt1, poly);
//=isInside1

var isInside2 = turf.inside(pt2, poly);
//=isInside2

Returns Boolean true if the Point is inside the Polygon; false if the Point is not inside the Polygon

---

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-inside

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

$ npm install turf