Easing

A library that implements easing functions in Swift.

Supported platforms:

• iOS, macOS, tvOS, watchOS and Linux (latest Ubuntu).

Type of supported functions:

• Quadratic
• Cubic
• Quartic
• Quintic
• Sine
• Circular
• Exponential
• Elastic
• Back
• Bounce

Each type has its own separate ease-In, ease-Out and ease-In-Out form.

The functions are design to accept a generic floating-point input parameter, and return a floating-point, denoting the rate of change of a property over time.

Supported argument types:

• Any type that conforms to the Real protocol, e.g.
  • Float
  • Float80
  • Double

Usage:

The Curve type allows access to all the different functions, for example:

let x: Float = 0.3
let y = Curve.quadratic.easeIn(x) // y = 0.09

let x: Double = 0.5
let y = Curve.sine.easeOut(x2) // y = 0.7071067811865    

Here’s an example of the use of the elastic ease-in-out function in an array of 75 points in the [0, 1] interval.

Installation:

Swift Package Manager (iOS, macOS, tvOS, watchOS and Linux)

Add Easing to your AwsomeProject, by adding the github URL to your Package.swift, e.g.:

// swift-tools-version:5.0

import PackageDescription

let package = Package(
   name: "AwsomeProject",
   dependencies: [
      .package(url: "https://github.com/manuelCarlos/Easing.git", .upToNextMajor(from: "2.0.0"))
   ],
   targets: [
      .target(
         name: "AwsomeProject",
         dependencies: ["Easing"])
   ]
)

• To quickly run the tests:

  (on macOS)

  swift test

  (on Linux)

  swift test --enable-test-discovery

Dependencies:

• Apple’s RealModule from the Swift Numerics package.