GeoJSONKit+Turf

This package provides various geospatial extensions for GeoJSONKit. It is a fork of turf-swift, which is ported from Turf.js.

Requirements

GeoJSONKitTurf requires Xcode 12.x and supports the following minimum deployment targets:

iOS 10.0 and above
macOS 10.12 (Sierra) and above
tvOS 10.0 and above
watchOS 3.0 and above

It’s also compatible with Linux (and possibly other platforms), as long as you have Swift 5.3 (or above) installed.

Installation

Swift Package Manager

To install GeoJSONKitTurf using the Swift Package Manager, add the following package to the dependencies in your Package.swift file:

.package(name: "GeoJSONKitTurf", url: "https://github.com/maparoni/geojsonkit-turf", from: "0.1.0")

Then use:

import GeoJSONKitTurf

Available functionality

This is a partial port of Turf.js, which adds the following functionality to GeoJSONKit‘s GeoJSON:

Turf.js	GeoJSONKit-Turf
turf-along	`GeoJSON.LineString.coordinateFromStart(distance:)`
turf-area	`GeoJSON.Polygon.area`
turf-bearing	`GeoJSON.Position.direction(to:)` `RadianCoordinate2D.direction(to:)`
turf-bezier-spline	`GeoJSON.LineString.bezier(resolution:sharpness:)`
turf-boolean-point-in-polygon	`GeoJSON.Polygon.contains(_:ignoreBoundary:)`
turf-center	`GeoJSON.Geometry.center()`
turf-center-of-mass	`GeoJSON.Geometry.centerOfMass()`
turf-centroid	`GeoJSON.Geometry.centroid()`
turf-circle	`GeoJSON.Polygon(center:radius:vertices:)`
turf-convex	`GeoJSON.convexHull()` `Collection<GeoJSON.Position>.convexHull()`
turf-destination	`GeoJSON.Position.coordinate(at:facing:)` `RadianCoordinate2D.coordinate(at:facing:)`
turf-distance	`GeoJSON.Position.distance(to:)` `RadianCoordinate2D.distance(to:)`
turf-helpers#degreesToRadians	`GeoJSON.Degrees.toRadians()`
turf-helpers#radiansToDegrees	`GeoJSON.DegreesRadians.toDegrees()`
turf-helpers#convertLength turf-helpers#convertArea	`Measurement.converted(to:)`
turf-length	`GeoJSON.LineString.distance(from:to:)`
turf-line-intersect	`GeoJSON.LineString.intersection(with:)`
turf-line-slice	`GeoJSON.LineString.sliced(from:to:)`
turf-line-slice-along	`GeoJSON.LineString.trimmed(from:distance:)` `GeoJSON.LineString.trimmed(from:to:)`
turf-midpoint	`mid(_:_:)`
turf-nearest-point-on-line	`GeoJSON.LineString.closestCoordinate(to:)`
turf-point-on-feature	`GeoJSON.Geometry.nearestPoint(to:)` `GeoJSON.Polygon.nearestPoint(to:)`
turf-polygon-smooth	`GeoJSON.Polygon.smooth(iterations:)`
turf-union	Not provided, but see ASPolygonKit
turf-simplify	`GeoJSON.simplify(options:)`
—	`GeoJSON.Direction.difference(from:)`
—	`GeoJSON.Direction.wrap(min:max:)`

CLI

Comes with a mini-CLI geokitten with these commands:

geokitten simplify $input to simplify a GeoJSON

Installation

Via SPM

First clone or download the repository, then run this:

swift build -c release
sudo cp .build/release/geokitten /usr/local/bin/geokitten

Via Mint

mint install maparoni/GeoJSONKit-Turf@main

If you get a permissions error, check this Mint issue.