Easily handle a geometric object model (points, linestrings, polygons etc.) and related topological operations (intersections, overlapping etc.). A type-safe, MIT-licensed Swift interface to the OSGeo's GEOS library routines.
For MapKit integration visit: https://github.com/GEOSwift/GEOSwiftMapKit
For MapboxGL integration visit: https://github.com/GEOSwift/GEOSwiftMapboxGL (volunteer needed to maintain GEOSwiftMapboxGL)
Version 5 constitutes a ground-up rewrite of GEOSwift. For full details and help migrating from version 4, see VERSION_5.md.
- A pure-Swift, type-safe, optional-aware programming interface
- WKT and WKB reading & writing
- Robust support for GeoJSON via Codable
- Thread-safe
- Swift-native error handling
- Extensively tested
- iOS 8.0+, tvOS 9.0+, macOS 10.9+ (CocoaPods, Carthage, Swift PM)
- Linux (Swift PM)
- Swift 5.1
GEOS is licensed under LGPL 2.1 and its compatibility with static linking is at least controversial. Use of geos without dynamic linking is discouraged.
-
Update your
Podfile
to include:use_frameworks! pod 'GEOSwift'
-
Run
$ pod install
-
Add the following to your Cartfile:
github "GEOSwift/GEOSwift" ~> 7.0.0
-
Finish updating your project by following the typical Carthage workflow.
-
Update the top-level dependencies in your
Package.swift
to include:.package(url: "https://github.com/GEOSwift/GEOSwift.git", from: "7.0.0")
-
Update the target dependencies in your
Package.swift
to include"GEOSwift"
In certain cases, you may also need to explicitly include geos as a dependency. See issue #195 for details.
// 1. From Well Known Text (WKT) representation
let point = try Point(wkt: "POINT(10 45)")
let polygon = try Geometry(wkt: "POLYGON((35 10, 45 45.5, 15 40, 10 20, 35 10),(20 30, 35 35, 30 20, 20 30))")
// 2. From a Well Known Binary (WKB)
let wkb: NSData = geometryWKB()
let geometry2 = try Geometry(wkb: wkb)
// 3. From a GeoJSON file:
let decoder = JSONDecoder()
if let geoJSONURL = Bundle.main.url(forResource: "multipolygon", withExtension: "geojson"),
let data = try? Data(contentsOf: geoJSONURL),
let geoJSON = try? decoder.decode(GeoJSON.self, from: data),
case let .feature(feature) = geoJSON,
let italy = feature.geometry
{
italy
}
Let's say we have two geometries:
GEOSwift let you perform a set of operations on these two geometries:
- equals: returns true if this geometric object is “spatially equal” to another geometry.
- disjoint: returns true if this geometric object is “spatially disjoint” from another geometry.
- intersects: returns true if this geometric object “spatially intersects” another geometry.
- touches: returns true if this geometric object “spatially touches” another geometry.
- crosses: returns true if this geometric object “spatially crosses’ another geometry.
- within: returns true if this geometric object is “spatially within” another geometry.
- contains: returns true if this geometric object “spatially contains” another geometry.
- overlaps: returns true if this geometric object “spatially overlaps” another geometry.
- relate: returns true if this geometric object is spatially related to another geometry by testing for intersections between the interior, boundary and exterior of the two geometric objects as specified by the values in the intersectionPatternMatrix.
Explore more, interactively, in the playground, which is available in the
GEOSwiftMapKit project. It can be
found inside GEOSwiftMapKit
workspace. Open the workspace in Xcode, build the
GEOSwiftMapKit
framework and open the playground file.
To make a contribution:
- Fork the repo
- Start from the
master
branch and create a branch with a name that describes your contribution - Run
$ carthage update
- Sign in to travis-ci.org (if you've never signed in before, CI won't run to verify your pull request)
- Push your branch and create a pull request to
master
- One of the maintainers will review your code and may request changes
- If your pull request is accepted, one of the maintainers should update the changelog before merging it
- Andrew Hershberger (@macdrevx)
- Virgilio Favero Neto (@vfn)
- Andrea Cremaschi (@andreacremaschi) (original author)
- GEOSwift was released by Andrea Cremaschi (@andreacremaschi) under a MIT license. See LICENSE for more information.
- GEOS stands for Geometry Engine - Open Source, and is a C++ library, ported from the Java Topology Suite. GEOS implements the OpenGIS Simple Features for SQL spatial predicate functions and spatial operators. GEOS, now an OSGeo project, was initially developed and maintained by Refractions Research of Victoria, Canada.