VelloAnimation
A parsed Lottie composition. Immutable after creation; holds the animation
data model (layers, shapes, keyframes) ready for frame-level rendering.
Module: elide.VelloAnimation
Support: Experimental
Interface VelloComposition
A parsed Lottie composition. Immutable after creation; holds the animation
data model (layers, shapes, keyframes) ready for frame-level rendering.
11 members: 11 undocumented
Static Methods
⚪ fromJSON(json)
Parse a Lottie JSON string into a composition.
⚪ fromBuffer(buffer)
Parse a Lottie file from a raw byte buffer (UTF-8 JSON).
Methods
⚪ getLayer(index)
Return metadata for a layer by index.
Properties
⚪ height
Composition width in pixels.
⚪ startFrame
First frame number (typically 0).
⚪ endFrame
Last frame number (exclusive).
⚪ frameCount
Total number of frames (endFrame - startFrame).
⚪ frameRate
Frames per second as declared in the Lottie file.
⚪ duration
Duration in seconds (frameCount / frameRate).
⚪ layerCount
Number of top-level layers.
---
Interface VelloLayerInfo
Return metadata for a layer by index.
Returns null if the index is out of range.
5 members: 5 undocumented
Properties
⚪ name
Read-only metadata about a single layer in a composition.
⚪ type
Layer name as declared in the Lottie file.
⚪ startFrame
First frame number (typically 0).
⚪ endFrame
Last frame number (exclusive).
⚪ isMask
Whether this layer is used as a matte/mask for another layer.
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Enum VelloLayerType
Layer type.
| Value | Description |
|---|
shape |
solid |
precomposition |
null |
image |
unknown |
Interface VelloAnimationRenderer
Stateful renderer that evaluates a composition at a given frame and emits
drawing commands. Maintains internal scratch buffers for performance; reuse
across frames.
4 members: 4 undocumented
Constructors
⚪ constructor()
Stateful renderer that evaluates a composition at a given frame and emits
Methods
⚪ renderFrame(composition, scene, frame, transform, alpha)
Render a single frame of the composition into the given scene.
⚪ renderAtTime(composition, scene, timeSeconds, transform, alpha)
Convenience: render at a time offset in seconds rather than a frame number.
⚪ renderFrameToScene(composition, frame, transform, alpha)
Render to a new VelloScene (allocates internally). Useful for one-shot
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Interface VelloAnimationPlayer
High-level animation player that manages playback state, looping, and
frame callbacks. Wraps a VelloComposition and a VelloAnimationRenderer.
Playback advances via explicit tick() calls (typically from requestAnimationFrame)
rather than internal timers, giving the caller full control.
19 members: 19 undocumented
Constructors
⚪ constructor(composition, options)
Stateful renderer that evaluates a composition at a given frame and emits
Methods
⚪ play()
Start playback from the current position.
⚪ pause()
Pause playback (currentFrame is preserved).
⚪ stop()
Stop playback and reset to the first frame.
⚪ seekToFrame(frame)
Seek to a specific frame. Clamps to the composition range.
⚪ seekToTime(timeSeconds)
Seek to a specific time in seconds.
⚪ tick(deltaSeconds, scene, transform, alpha)
Advance playback by the given delta time (in seconds) and render the
⚪ onFrame(callback)
Register a callback invoked on every frame change during tick().
⚪ onLoop(callback)
Register a callback invoked when a loop iteration completes.
⚪ onComplete(callback)
Register a callback invoked when playback reaches the end and is not
⚪ removeAllListeners()
Remove all registered callbacks.
⚪ destroy()
Release internal resources. The player is unusable after this.
Properties
⚪ composition
Render a single frame of the composition into the given scene.
⚪ state
The underlying composition.
⚪ currentFrame
Current frame number.
⚪ currentTime
Current playback time in seconds.
⚪ speed
Current playback time in seconds.
⚪ loop
Whether the animation loops.
⚪ loopCount
Number of completed loops (resets on seek).
---
Callback VelloFrameCallback
Register a callback invoked on every frame change during tick().
The callback receives the current frame number.
---
Callback VelloLoopCallback
Register a callback invoked when a loop iteration completes.
The callback receives the loop count.
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Callback VelloCompleteCallback
Register a callback invoked when playback reaches the end and is not
looping (or has exhausted the loop count).
---
Dictionary VelloPlayerOptions
High-level animation player that manages playback state, looping, and
frame callbacks. Wraps a VelloComposition and a VelloAnimationRenderer.
Playback advances via explicit tick() calls (typically from requestAnimationFrame)
rather than internal timers, giving the caller full control.
6 members: 6 undocumented
Properties
⚪ speed
Current playback time in seconds.
⚪ loop
Whether the animation loops.
⚪ maxLoops
Maximum number of loops when loop is "loop" or "ping-pong".
⚪ startFrame
First frame number (typically 0).
⚪ endFrame
Last frame number (exclusive).
⚪ autoplay
Whether to auto-play on construction. Default false.
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Enum VelloPlaybackState
Current playback state.
| Value | Description |
|---|
idle |
playing |
paused |
stopped |
Enum VelloLoopMode
Whether the animation loops.
| Value | Description |
|---|
none |
loop |
ping-pong |