Install

Add to your Unity project as a git package using the package manager.

https://github.com/Less3Design/L3-tween.git

Usage

L3 Tween is based around exclusively supporting the way I like to write tweens:

private Tween moveTween;

void DoAnimation()
{
    Vector3 startPos = transform.position;
    Vector3 endPos = Random.insideUnitSphere;
    //cancel previous tween, start a new one
    moveTween = moveTween.Cancel().New(1f).SetOnUpdate((t) => {
      transform.position = Vector3.Lerp(startPos,endPos,t);
    });
}

Supporting just a single use case lets us keep the business logic to only a couple hundred lines. Here is all the state we mainatin:

public class TweenObject
{
    public ushort id;
    public ushort version;
    public bool active;

    public float fromValue;
    public float toValue;
    public float duration;
    public float elapsedTime;
    public Ease easeType;
    public TweenUpdateType deltaTimeType;

    public Action<float> onUpdate;
    public Action onComplete;
    public Action onCancel;
}

Performance

It's super good enough. If you need to animate many thousands of objects at once I reccomend treating that like a particle system, don't use tweens.

• TweenObjects are pooled
• Every object is iterated every frame, but if no tweens are active the process takes < .01ms
• The biggest cost will be whatever you allocate and execute inside tweens
• No async job burst etc... because the goal is to keep code as simple as possible

Video showing the system allocating tweens through its pool

Recording.2025-12-20.170935.mp4

TODO

• Init custom pool size
• Auto pool expansion
• Probably some perf to improve, could avoid iterating inactive tweens every frame