A Leaflet-friendly API for point in polygon operations, using substack's point in polygon library.
With browserify
npm install leaflet-pip
Resolve for a CDN/packaged version:
https://unpkg.com/leaflet-pip@latest/leaflet-pip.js
var gjLayer = L.geoJson(statesData);
var results = leafletPip.pointInLayer([-88, 38], gjLayer);
// results is an array of L.Polygon objects containing that point
Point can be:
- A two-element array of
[lng, lat]
- A
L.LatLng
object
Layer must be:
- A
L.geoJSON
layer
first
can be:
boolean
:true
to accept the first match, orfalse
to return all polygons containing this point. This can be useful if you know that your polygons are non-overlapping or don't care about more than one result, since it will be much faster. By default, this is false and all matches are returned.
Returns:
An array of polygons in which the given point resides, an empty array if there
are none. The polygons are returned as direct sublayers, so they can include
MultiPolygons. You can call pointInLayer
again on those if you want the
sub-polygon result.
Leaflet treats literate coordinate arrays as [lat, lon]
, unlike GeoJSON
and any true scotsman. leaflet-pip
treats literate coordinate arrays as [lon, lat]
, but if you set bassackwards
to true, it'll do things the Leaflet/Google Maps API way.