@turf/projection

What is @turf/projection?

@turf/projection is a module within the Turf.js library that provides functionality for projecting geographical coordinates. It allows for the conversion of coordinates between different coordinate reference systems (CRS), which is essential for various geospatial analyses and visualizations.

What are @turf/projection's main functionalities?

toMercator

Converts a GeoJSON object from geographic coordinates (longitude, latitude) to Mercator (x, y) coordinates.

const turf = require('@turf/turf');
const point = turf.point([-75.343, 39.984]);
const projected = turf.toMercator(point);
console.log(projected);

toWgs84

Converts a GeoJSON object from Mercator (x, y) coordinates to geographic coordinates (longitude, latitude).

const turf = require('@turf/turf');
const point = turf.point([0, 0]);
const projected = turf.toWgs84(point);
console.log(projected);

Other packages similar to @turf/projection

proj4

Proj4 is a JavaScript library for converting coordinates between different coordinate reference systems. It is highly versatile and supports a wide range of projections. Compared to @turf/projection, proj4 offers more extensive support for various CRS and is often used in more complex geospatial applications.

README

@turf/projection

toMercator

Converts a WGS84 GeoJSON object into Mercator (EPSG:900913) projection

Parameters

• geojson GeoJSON WGS84 GeoJSON object
• mutate [boolean] allows GeoJSON input to be mutated (significant performance increase if true) (optional, default false)

Examples

var pt = turf.point([-71,41]);
var converted = turf.toMercator(pt);

//addToMap
var addToMap = [pt, converted];

Returns GeoJSON true/false

toWgs84

Converts a Mercator (EPSG:900913) GeoJSON object into WGS84 projection

Parameters

• geojson GeoJSON Mercator GeoJSON object
• mutate [boolean] allows GeoJSON input to be mutated (significant performance increase if true) (optional, default false)

Examples

var pt = turf.point([-7903683.846322424, 5012341.663847514]);
var converted = turf.toWgs84(pt);

//addToMap
var addToMap = [pt, converted];

Returns GeoJSON true/false

---

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/projection

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

$ npm install @turf/turf

Changelog

4.7.0

🚀 New Modules

[@turf/projection][projection]

• toMercator: Converts a WGS84 GeoJSON object into Mercator (EPSG:900913) projection
• toWgs84: Converts a Mercator (EPSG:900913) GeoJSON object into WGS84 projection

(PR https://github.com/Turfjs/turf/pull/927 - Author @stebogit)

[@turf/point-to-line-distance][point-to-line-distance]

Returns the minimum distance between a {@link Point} and a {@link LineString}, being the distance from a line the minimum distance between the point and any segment of the LineString.

(PR https://github.com/Turfjs/turf/pull/925 - Author @stebogit)

[@turf/boolean-within][boolean-within]

Boolean-within returns true if the first geometry is completely within the second geometry. The interiors of both geometries must intersect and, the interior and boundary of the primary (geometry a) must not intersect the exterior of the secondary (geometry b). Boolean-within returns the exact opposite result of the [@turf/boolean-contains][boolean-contains].

(PR https://github.com/Turfjs/turf/pull/924 - Author @rowanwins)

🏅 New Features/Enhancements

• Updates [@turf/unkink-polygon][unkink-polygon] testing & added flattenEach instead of using flatten. (PR https://github.com/Turfjs/turf/pull/889)
• [@turf/concave][concave] refactoring, replacing [@turf/union][union] with geojson-dissolve to increase speed and added support to null geometries (PR https://github.com/Turfjs/turf/pull/907 - Contributor @stebogit @DenisCarriere)
• Adds doc note on [@turf/polygonize][polygonize] about "Edges must be correctly noded" (PR https://github.com/Turfjs/turf/pull/898 - Contributor @stebogit @NickCis)
• Adds support to foreign Members to [@turf/clone][clone] (PR https://github.com/Turfjs/turf/pull/904 - Contributor @DenisCarriere)
• Extends support of any GeoJSON to [@turf/simplify][simplify] (PR https://github.com/Turfjs/turf/pull/903 - Contributor @DenisCarriere @stebogit)
• Adds new isNumber function and improves type checking for few [@turf/helpers][helpers] methods (PR https://github.com/Turfjs/turf/pull/920 - Contributor @DenisCarriere @stebogit)
• Adds throw errors to invalid MultiPolygons for [@turf/simplify][simplify] (PR https://github.com/Turfjs/turf/pull/922 - Contributor @DenisCarriere)

🐛 Bug Fixes

• Fixes @turf/bbox-clip point intersection handling, adding sanity-checks the lineclip output (PR https://github.com/Turfjs/turf/pull/886)
• Fixes [@turf/line-split][line-split] endpoint case handling applying [@turf/truncate][truncate] on splitter (PR https://github.com/Turfjs/turf/pull/892 and https://github.com/Turfjs/turf/pull/855 - Contributor @stebogit)
• Fixes [@turf/intersect][intersect] throwing "uncaught exception", adding [@turf/truncate][truncate] to inputs and returning Feature<null> if no geometry (PR https://github.com/Turfjs/turf/pull/890 - Contributor @stebogit @vicvolk)
• Fixes [@turf/hex-grid][hex-grid] not properly cloning the last ring vertex (PR https://github.com/Turfjs/turf/pull/897 - Contributor @stebogit @DenisCarriere)
• Fixes [@turf/boolean-disjoint][boolean-disjoint] incorrect behaviour where a poly was completely contained within another poly (PR https://github.com/Turfjs/turf/pull/908 - Contributor @rowanwins)
• Fixes [@turf/simplify][simplify] process pending on particular geometries, applying [@turf/clean-coords][clean-coords] to input. (PR https://github.com/Turfjs/turf/pull/903 - Contributor @stebogit @DenisCarriere)
• Fixes boolean properties not being translated with [@turf/clone][clone] (PR https://github.com/Turfjs/turf/pull/909 - Contributor @DenisCarriere)
• Fixes [@turf/boolean-contains][boolean-contains] incorrect output when checking two polygons (PR https://github.com/Turfjs/turf/pull/923 - Contributor @rowanwins @DenisCarriere)