swiss-projection

Convert points and GeoJSON objects between LV03(EPSG:21781), LV95(EPSG:2056) and WGS84(EPSG:4326).

For a lightweight version without dependencies, check out swiss-projection-light.

Install

NPM

$ npm install swiss-projection

var ch = require('swiss-projection')

Browser

Download swiss-proj.min.js

<script src="swiss-proj.min.js"></script>

The library is accessible through the global variable ch.

Usage

ch.<input-projection>.to<output-projection>.point([<x>,<y>], <round>)
// or 
ch.<input-projection>.to<output-projection>.GeoJSON(<geojson-object>, <round>)

<round> is a boolean (defaults to false). If true, the result will be rounded to closest integer for results in LV03 or LV95 and to 0.000001 in WGS.

Example 1: LV03 point to WGS84

ch.lv03.toWgs.point([600000, 200000])

// returns
// [ 7.4386329497797306, 46.95108228114304 ]

ch.lv03.toWgs.point([600000, 200000], true)

// returns
// [ 7.438633, 46.951082 ]

Exemple 2: WGS GeoJSON feature to LV95

var feature = {
    type: 'Feature', properties: {}, geometry: { type: 'Point', coordinates: [7.438633, 46.951082] }
}

ch.wgs.toLv95.GeoJSON(feature, true)

// returns

//{ type: 'Feature',
// properties: {},
// geometry: {
//  type: 'Point',
//  coordinates: [ 2600000, 1200000 ] 
// },
// crs: {
//  type: 'name',
//  properties: { name: 'urn:ogc:def:crs:EPSG::2056' } 
// } 
//}

This method works for both FeatureCollection and Feature.