frames/skills/frames-animation/adapters/lottie.md

name, description

name	description
frames-lottie	Lottie and dotLottie adapter patterns for Frames. Use when embedding lottie-web JSON animations, .lottie files, @lottiefiles/dotlottie-web players, registering instances on window.__hfLottie, or making After Effects exports deterministic in Frames.

Lottie for Frames

Frames can seek both lottie-web and dotLottie players through its lottie runtime adapter. Lottie is a strong fit because the animation timeline is already encoded in the asset; Frames only needs a player object it can seek.

Contract

• Load assets from local project files, usually under assets/.
• Set autoplay: false.
• Prefer loop: false unless the user explicitly wants a loop.
• Register every returned animation or player on window.__hfLottie.
• Keep the Lottie container dimensions stable with CSS.

The adapter seeks lottie-web with goToAndStop(timeMs, false) and dotLottie with frame or percentage APIs depending on player shape.

lottie-web Pattern

<div id="logo-lottie" class="lottie-layer"></div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/bodymovin/5.12.2/lottie.min.js"></script>
<script>
  const anim = lottie.loadAnimation({
    container: document.getElementById("logo-lottie"),
    renderer: "svg",
    loop: false,
    autoplay: false,
    path: "assets/logo-reveal.json",
  });

  window.__hfLottie = window.__hfLottie || [];
  window.__hfLottie.push(anim);
</script>

.lottie-layer {
  width: 100%;
  height: 100%;
}

dotLottie Pattern

<canvas id="product-lottie" class="lottie-canvas"></canvas>
<script src="https://unpkg.com/@lottiefiles/dotlottie-web"></script>
<script>
  const player = new DotLottie({
    canvas: document.getElementById("product-lottie"),
    src: "assets/product-flow.lottie",
    autoplay: false,
    loop: false,
  });

  window.__hfLottie = window.__hfLottie || [];
  window.__hfLottie.push(player);
</script>

.lottie-canvas {
  width: 100%;
  height: 100%;
  display: block;
}

Multiple Animations

Push each player into the same registry:

window.__hfLottie = window.__hfLottie || [];
window.__hfLottie.push(backgroundAnim);
window.__hfLottie.push(iconAnim);
window.__hfLottie.push(confettiAnim);

Frames seeks them all to the same composition time.

Composition Duration

The render engine needs the composition's total length. GSAP timelines report duration automatically; a Lottie-only composition has no timeline object, so the runtime reads the registered animation's native length directly — totalFrames / frameRate for lottie-web, or the player's own duration for dotLottie. data-duration on the root element is optional for Lottie compositions: as long as every animation is registered on window.__hfLottie (per the contract above), the runtime has a finite duration to work with even when you set loop: true.

Good Uses

• After Effects exports that are already known to render correctly in lottie-web.
• Logo reveals, icon loops, decorative accents, and product UI motion.
• Translating Remotion Lottie usage into plain Frames HTML.

Avoid

• Relying on remote path URLs at render time.
• Starting playback with play().
• Assuming unsupported After Effects effects will survive export. Test the JSON or .lottie file in a browser first.
• Loading a player asynchronously and registering it after Frames validation has already inspected the page.

Validation

After editing a Lottie composition:

npx @hanzo/frames lint
npx @hanzo/frames check

Credits And References

• Frames adapter source: packages/core/src/runtime/adapters/lottie.ts.
• Duration auto-inference: packages/core/src/runtime/init.ts (resolveAdapterDurationFloorSeconds), getInferredDurationSeconds in the adapter above.
• lottie-web by Airbnb: https://github.com/airbnb/lottie-web
• lottie-web loadAnimation options: https://github.com/airbnb/lottie-web/wiki/loadAnimation-options
• dotLottie web player methods by LottieFiles: https://developers.lottiefiles.com/docs/dotlottie-player/dotlottie-web/methods