TwiiK Sprite Animator

A lightweight sprite animation system for Unity, designed as an alternative to Mecanim for simple 2D sprite-based animations. I'm trying to use it in 3 projects currently and I'm adding to is as I go.

Features

• ScriptableObject-based animation assets
• No Mecanim state machine spaghetti - direct sprite animation playback
• Supports looping, ping-pong, and one-shot animations
• Variable playback speed
• Custom editor with frame thumbnails, animation preview and playback controls

Quick Start

1. Create a SpriteAnimation Asset

Right-click in the Project window and select Create > Sprite Animation.

Configure the asset:

• Frames: Array of sprites for the animation
• FPS: Playback speed in frames per second
• Looping: Whether the animation loops
• Ping Pong: Play forwards then backwards
• Show Blank Frame At The End: Display nothing after the last frame (useful for explosions)

Note: All these properties can be set at runtime through the SpriteAnimator component as well to have for example a movement animation that depends on the character speed.

2. Add the SpriteAnimator Component

Add SpriteAnimator to a GameObject with a SpriteRenderer component.

Assign your SpriteAnimation assets to the Animations array.

3. Play Animations

SpriteAnimator animator = GetComponent<SpriteAnimator>();

// Play an animation by name
animator.Play("Walk");

// Play at half speed
animator.Play("Walk", 0.5f);

// Play in reverse
animator.Play("Walk", -1f);

// Play at double speed, don't reset if already playing
animator.Play("Run", 2f, reset: false);

API Reference

SpriteAnimator

Properties

Property	Type	Description
animations	SpriteAnimation[]	Array of available animations
currentAnimation	SpriteAnimation	Currently playing animation
currentFrame	int	Current frame index
fps	int	Current playback FPS (can override animation default)
looping	bool	Whether current animation loops
pingPong	bool	Whether current animation ping-pongs
reverse	bool	Whether playing in reverse

Methods

// Play animation by name
void Play(string name, float speed = 1, bool reset = true)

// Play animation that cannot be interrupted by other Play() calls
void PlayOnceUninterrupted(string name)

// Get animation duration in seconds
float GetAnimationLength(string name)

// Check if animation reached its end
bool ReachedEndOfAnimation()

// Stop playback
void Stop()

Events

// Fired when animation reaches its end
UnityEvent OnAnimationEndEvent

SpriteAnimation (ScriptableObject)

Field	Type	Description
frames	Sprite[]	Animation frames
fps	int	Default playback speed
looping	bool	Loop continuously
pingPong	bool	Play forwards then backwards
showBlankFrameAtTheEnd	bool	Show blank sprite after last frame

Editor Features

The custom inspector provides:

• Frame Thumbnails: Visual grid of all animation frames
• Playback Controls: Play/Pause/Stop buttons with frame slider
• Animated Preview: Real-time preview in the inspector preview panel

Note: The built-in array inspector for the animation frames allows you to easily reorder animation frames and duplicate frames to extend parts of the animation.

Usage Examples

Listen for Animation End

void Start() {
    animator.OnAnimationEndEvent.AddListener(OnAnimationEnd);
}

void OnAnimationEnd() {
    Debug.Log("Animation finished!");
}

Manual Frame Control

// Pause animation and control frame manually
animator.fps = 0;
animator.currentFrame = 3;

Uninterruptible Attack Animation

void Attack() {
    // This will play to completion even if Play() is called
    animator.PlayOnceUninterrupted("Attack");
}

void Update() {
    // These calls won't interrupt the attack animation
    if (isMoving) {
        animator.Play("Walk");
    } else {
        animator.Play("Idle");
    }
}

License

MIT License