N:Easing

Compact easing library for Unity

N:Easing is a small easing library offering a lot of different and efficient ways to ease & tween in Unity. The library itself is rather barebone : think of it as a whole lot of alternatives to lerp. It supports Mathematics's float, float2, float3, float4, double, double2, double3, double4, int, int2, int3, int4 & quaternion.

It is straighforward to use and extend. Note : float3 include support for Slerp equations on top of Penner's ones. (i.e backEaseOutSlerp)

Features

N:Easing provides multiples ways to interact with the most common easing equations, as well as using AnimationCurve for even more custom easing.

1 - Inline easing using partial class

As easy as Lerp.

equation( T from, T to, float time )

    using static Nebukam.Easing.ease;

    float f = linear(0f, 10f, 0.5f);
    // output : 5.0

2 - Typed & cached static equation delegates

Static classes exist for each types; Using Unity.mathematics naming conventions with the first letter capitalized : Float for float etc.

Type.Equation( T from, T to, float time, float duration)

    using Nebukam.Easing;

    Float.Back.In(0f, 10f, 0.5f, 1f);
    // output : 5.0

Pre-cached delegate are accessed as group variants, making it easy to choose a specific easing equation :

    Float.Back.Out
    Float.Back.In
    Float.Back.InOut
    Float.Back.OutIn

3 - Extensions

Extensions work in similar ways to the partial class, and add easing methods as extensions to value types, using normalized values (like lerp does)

    using Nebukam.Easing.Extensions;

    float foo = 0f;
    float bar = foo.linear(10f, 0.5f);
    //bar == 5.0f

    bar = (0f).linear(10f, 0.5f);
    //bar == 5.0f

4 - Tween object

The Tween class is a lightweight-ish Tween object. It keeps track of the start, end, value, duration & current time, as well as holding a reference to an Easing.Ease<T> delegate. It can be implicitly casted to its original type, and as such is easy to work with. Since one of its property is managed (delegate), it is unfit to work with Unity's Job system.

    Tween<float> myTween = new Tween(Float.Linear, 0f, 10f, 1f);

    myTween.Advance(0.1f);
    //(float)myTween output : 1.0f;
    myTween.Advance(0.4f);
    //(float)myTween output : 5.0f;
    myTween.Advance(0.5f);
    //(float)myTween output : 10.0f;

    myTween.At(0.5f);
    //output : 5.0f;

5 - Custom curve

The CurveEase allows you to easily access & use easing delegates bound to a given AnimationCurve, and use them with Tweens (or standalone).

    CurveEase c = new CurveEase(someAnimationCurve);
    c.sampling = Float.Linear; //Default value

    Tween<float> t = new Tween<float>(c, 0f, 10f, 1f);
    t.At(0.5f);
    //output with linear curve : 5.0f

Out-of-the-box easings :

Easing	Out	In	InOut	OutIn
Linear	linear	-	-	-
Expo	expoEaseOut	expoEaseIn	expoEaseInOut	expoEaseOutIn
Circular	circEaseOut	circEaseIn	circEaseInOut	circEaseOutIn
Quad	quadEaseOut	quadEaseIn	quadEaseInOut	quadEaseOutIn
Sine	sineEaseOut	sineEaseIn	sineEaseInOut	sineEaseOutIn
Cubic	cubicEaseOut	cubicEaseIn	cubicEaseInOut	cubicEaseOutIn
Quartic	quartEaseOut	quartEaseIn	quartEaseInOut	quartEaseOutIn
Quintic	quintEaseOut	quintEaseIn	quintEaseInOut	quintEaseOutIn
Elastic	elasticEaseOut	elasticEaseIn	elasticEaseInOut	elasticEaseOutIn
Bounce	bounceEaseOut	bounceEaseIn	bounceEaseInOut	bounceEaseOutIn
Back	backEaseOut	backEaseIn	backEaseInOut	backEaseOutIn

Hows

Installation

To be used with Unity's Package Manager.
⚠ Git Dependency Resolver For Unity must be installed before in order to fetch nested git dependencies. (See the Installation troubleshooting if you encounter issues).

See Unity's Package Manager : Getting Started

Dependencies

Unity.Mathematics 1.1.0 -- com.unity.mathematics

Credits

Original easing equations are based on Robert Penner's easing functions.

Installation Troubleshooting

After installing this package, Unity may complain about missing namespace references error (effectively located in dependencies). What Git Dependency Resolver For Unity does, instead of editing your project's package.json, is create local copies of the git repo effectively acting as custom local packages. Hence, if you encounter issues, try the following:

In the project explorer, do a Reimport All on the Packages folder (located at the same level as Assets & Favorites). This should do the trick.
Delete Library/ScriptAssemblies from you project, then Reimport All.
Check the Resolver usage for users

Nebukam / com.nebukam.easing