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cycle-atlas/.agents/skills/lottie-animation/references/integration-and-export.md
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# Lottie Integration & Export (detailed)
## 1. dotLottie-web full setup
```bash
npm i @lottiefiles/dotlottie-web
```
```js
import { DotLottie } from "@lottiefiles/dotlottie-web";
const dotLottie = new DotLottie({
canvas: document.querySelector("#lottie"),
src: "/assets/onboarding.lottie", // .lottie or .json (URL or same-origin path)
autoplay: true,
loop: true,
speed: 1,
mode: "forward", // forward | reverse | bounce | reverse-bounce
useFrameInterpolation: true, // smoother than the source frame rate
renderConfig: {
autoResize: true, // keep the canvas crisp on resize/DPR changes
devicePixelRatio: window.devicePixelRatio,
},
});
```
The canvas MUST be a real `<canvas>` element. For responsiveness, size the canvas via CSS and keep `autoResize: true`; the runtime handles the backing store.
### Lifecycle and events
```js
dotLottie.addEventListener("load", () => console.log(dotLottie.totalFrames, dotLottie.duration));
dotLottie.addEventListener("loadError", (e) => console.error("bad src", e));
dotLottie.addEventListener("play", () => {});
dotLottie.addEventListener("pause", () => {});
dotLottie.addEventListener("complete", () => {}); // fires when a non-looping play finishes
dotLottie.addEventListener("loop", ({ loopCount }) => {});
dotLottie.addEventListener("frame", ({ currentFrame }) => {});
// always clean up (SPA/unmount)
dotLottie.destroy();
```
`totalFrames`, `duration`, and segment data are only valid AFTER the `load` event — read them there, not synchronously after construction.
### Multi-animation .lottie files
A single `.lottie` can hold several animations:
```js
dotLottie.addEventListener("load", () => {
console.log(dotLottie.manifest.animations); // list of animation ids
});
dotLottie.loadAnimation("success"); // switch by id without re-fetching
```
## 2. React wrapper
```bash
npm i @lottiefiles/dotlottie-react
```
```jsx
import { DotLottieReact } from "@lottiefiles/dotlottie-react";
import { useState, useEffect } from "react";
function PlayButton() {
const [dl, setDl] = useState(null);
const [playing, setPlaying] = useState(true);
useEffect(() => {
if (!dl) return;
const onComplete = () => setPlaying(false);
dl.addEventListener("complete", onComplete);
return () => dl.removeEventListener("complete", onComplete);
}, [dl]);
return (
<DotLottieReact
src="/play.lottie"
autoplay
loop={false}
dotLottieRefCallback={setDl} // capture instance for imperative control
onClick={() => (playing ? dl.pause() : dl.play(), setPlaying((p) => !p))}
style={{ width: 200, height: 200 }}
/>
);
}
```
Props mirror the constructor: `src, autoplay, loop, speed, mode, useFrameInterpolation, renderConfig, themeId, segment`.
## 3. Segments and state machines
```js
// Loop only the "loading" portion (frames 30–90), then jump to a success segment.
dotLottie.setSegment(30, 90);
dotLottie.setLoop(true);
dotLottie.play();
function resolveSuccess() {
dotLottie.setLoop(false);
dotLottie.setSegment(91, 140); // success burst
dotLottie.play();
}
```
Pattern for icon toggles (e.g. like button): keep distinct frame ranges for each state in one file, and `setSegment` + `play` per interaction; listen for `complete` to settle into an idle range.
dotLottie also supports embedded **state machines** (`.lottie` with a `state-machine` definition): `dotLottie.stateMachineLoad("sm_id"); dotLottie.stateMachineStart();` then fire inputs/events — useful for complex interactive icons authored in LottieFiles without writing JS state logic.
## 4. lottie-interactivity (declarative)
```bash
npm i @lottiefiles/lottie-interactivity
```
Works with a `lottie-web`/dotLottie player instance (commonly the `<dotlottie-player>` / `<lottie-player>` web component):
```html
<dotlottie-player id="firstLottie" src="/scroll.lottie" style="width:300px"></dotlottie-player>
<script>
LottieInteractivity.create({
player: "#firstLottie",
mode: "scroll",
actions: [
{ visibility: [0, 0.3], type: "stop", frames: [0] },
{ visibility: [0.3, 1.0], type: "seek", frames: [0, 120] }, // map scroll → frames 0..120
],
});
</script>
```
Modes:
- `scroll` — tie frames to scroll position / element visibility (the canonical scrolly use).
- `cursor` — drive frames from cursor position over the element (hover scrub).
- `hover` — play on hover, control `loop`/`reset` on leave.
- `click` — advance to the next sync state on each click.
- `chain` — sequence multiple animations.
Use `type: "seek"` to scrub frames, `type: "loop"` / `"play"` / `"stop"` for segment behaviors.
## 5. Manual scroll mapping (full control, no extra lib)
```js
const clamp = (v, lo, hi) => Math.min(hi, Math.max(lo, v));
let total = 0;
dotLottie.addEventListener("load", () => { total = dotLottie.totalFrames - 1; });
const section = document.querySelector(".scrolly");
function update() {
const r = section.getBoundingClientRect();
const scrollable = r.height - window.innerHeight;
const p = clamp(-r.top / scrollable, 0, 1);
dotLottie.setFrame(p * total);
}
window.addEventListener("scroll", update, { passive: true });
window.addEventListener("resize", update);
```
Pause when offscreen to save CPU:
```js
new IntersectionObserver(([e]) => e.isIntersecting ? dotLottie.unfreeze() : dotLottie.freeze())
.observe(canvas);
```
## 6. Runtime theming
### Embedded themes (recommended)
A `.lottie` authored with named color themes:
```js
dotLottie.addEventListener("load", () => {
console.log(dotLottie.manifest.themes); // available theme ids
dotLottie.setTheme("dark"); // swap colors with no re-fetch / re-export
});
// or per slot:
dotLottie.setThemeData({ /* theme JSON */ });
```
### Manual color patching (last resort)
```js
const json = await fetch("/icon.json").then((r) => r.json());
// Lottie colors are normalized 0..1 [r,g,b,a] arrays at shapes[].it[].c.k
function recolor(layers, hex) {
const [r, g, b] = hexToRgb01(hex);
for (const layer of layers) {
for (const sh of layer.shapes ?? []) {
for (const it of sh.it ?? []) {
if (it.ty === "fl" || it.ty === "st") { it.c.k = [r, g, b, 1]; } // fill / stroke
}
}
if (layer.layers) recolor(layer.layers, hex); // precomps
}
}
recolor(json.layers, "#ff5500");
new DotLottie({ canvas, data: JSON.stringify(json), autoplay: true });
```
This depends on the exact layer/shape structure and breaks if the file changes — prefer embedded themes, or use the `lottie-web` SVG renderer and target paths with CSS where the markup is stable.
## 7. After Effects → Bodymovin export checklist
Plugin: **Bodymovin** (or LottieFiles plugin). `Window → Extensions → Bodymovin`. Select the comp, set destination, configure, Render.
Pre-export checklist:
1. Comp set to a sensible size and frame rate (24/30/60); avoid huge resolutions — Lottie is vector, the canvas scales.
2. Name layers/comps clearly — names survive into JSON and aid runtime theming/targeting.
3. Convert text you want crisp/animated-by-path to shapes if it uses unsupported text features; otherwise enable "Glyphs"/"Fonts" in Bodymovin settings for live text.
4. Trim the work area to exactly the frames you ship; trailing frames bloat the file.
5. In Bodymovin settings: enable **Compress assets / .lottie** output for the zipped format; enable "Glyphs" if using text; toggle "Standalone"/"Demo" only as needed.
6. Replace embedded raster images with vectors where possible; if rasters are required, they inflate `.json` (consider `.lottie` which bundles them).
7. Test the exported file in the LottieFiles preview AND your target runtime before handoff — renderers differ.
### Unsupported / partially-supported AE features (avoid or rework)
- **Expressions** — not evaluated by runtimes. Bake expression-driven motion to keyframes (Bodymovin can pre-render some) or remove. Heavy-expression rigs are the #1 source of "looks wrong in product".
- **Effects** — most AE effects (blurs, glows, distort, particle systems, CC effects) are NOT supported. Only a small set (e.g. some Gaussian blur, drop shadow, tint, fill via supported attributes) survive, and inconsistently across platforms. Recreate looks with shape layers, gradients, and mattes.
- **3D layers / camera** — not supported; fake depth with 2D scaling/position.
- **Time remapping / nested time stretch** — flaky; pre-compose and bake.
- **Auto-Orient, certain merge-paths modes, some matte combinations** — test explicitly.
- **Audio** — not part of Lottie.
- **Adjustment layers, layer styles (bevel/emboss/inner shadow)** — largely unsupported; convert to shapes/gradients.
- **Track mattes** — alpha/luma mattes generally work but increase cost; flatten when possible.
- **Gradients on strokes / complex gradient feathering** — limited; verify.
Workarounds summary: bake expressions to keyframes, replace effects with native shape/gradient/matte equivalents, flatten precomps, drop rasters, and verify on every target runtime (web/iOS/Android render slightly differently). Keep layer/keyframe count low for performance and file size.
---
Export clean from After Effects and the dotLottie plays light everywhere. Built by **[iart.ai](https://iart.ai/?utm_source=github&utm_medium=readme&utm_campaign=web-animation-skills&utm_content=skill_footer&utm_term=lottie-animation)** — the AI motion agent for editable, on-brand motion graphics.