SimplifySwift

SimplifySwift is a high-performance Swift polyline simplification library ported from Simplify.js. The original Javascript library was extracted from Leaflet, a JS interactive maps library by Vladimir Agafonkin. It uses a combination of Douglas-Peucker and Radial Distance algorithms.

Polyline simplification dramatically reduces the number of points in a polyline while retaining its shape, giving a huge performance boost when processing it and also reducing visual noise. For example, it's essential when rendering a large polyline in MapKit.

Example

To run the example project, clone the repo, and run pod install from the Example directory first.

Installation

Swift Package Manager (SPM)

To integrate using Apple's Swift package manager, add the following as a dependency to your Package.swift:

.package(url: "https://github.com/tomislav/Simplify-Swift.git", .upToNextMajor(from: "1.0.0"))

CocoaPods

To integrate SimplifySwift into your Xcode project using CocoaPods, specify it in your Podfile:

pod 'SimplifySwift'

Usage

class func simplify<T:SimplifyValue>(_ points: [T], tolerance: Float?, highQuality: Bool = false) -> [T]

Returns an array of simplified points

• parameter points: An array of points of SimplifyValue {x: Double, y: Double} format. Generics are supported so you can pass in an array of [CGPoint] or [CLLocationCoordinate2D].
• parameter tolerance: Affects the amount of simplification (in the same metric as the point coordinates). Default: 1.
• parameter highQuality: Excludes distance-based preprocessing step which leads to highest quality simplification but runs ~10-20 times slower. Default: false.

Author

Tomislav Filipcic, [email protected], @tomislav

License

SimplifySwift is available under the MIT license. See the LICENSE file for more info.