[SOLVED] Find in which polygon a GeoJSON point lies in, in NodeJS

Find in which polygon a GeoJSON point lies in, in NodeJS

Given a defined (lat, lon) geo-point I'm trying to find in which polygon this point lies in. I suppose iterating over all the polygons is not efficient. Is there available any function or library for NodeJS that does this?

const polygon = getPolygonFromPoint(FeatureCollection, x, y);

There are no overlapping polygons, actually I'm using this to detect in which district of a certain country a defined GPS coordinates point lies in.

Solution

I implemented that with the library polygon-lookup

const PolygonLookup = require('polygon-lookup')
const featureCollection = {
    type: 'FeatureCollection',
    features: [{
        type: 'Feature',
        properties: { id: 'bar' },
        geometry: {
            type: 'Polygon',
            coordinates: [ [ [ 0, 1 ], [ 2, 1 ], [ 3, 4 ], [ 1, 5 ] ] ]
        }
    }]
}
var lookup = new PolygonLookup(featureCollection)
var poly = lookup.search(1, 2)
console.log(poly.properties.id) // bar