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30-seconds-of-code/snippets/recordAnimationFrames.md

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### recordAnimationFrames
Invokes the provided callback on each animation frame.
Use recursion. Provided that `running` is `true`, continue invoking `window.requestAnimationFrame()` which invokes the
provided callback. Return an object with two methods `start` and `stop` to allow manual control of the recording. Omit the second argument, `autoStart`, to implicitly call `start` when the function is invoked.
```js
const recordAnimationFrames = (callback, autoStart = true) => {
let running = true, raf
const stop = () => {
running = false
cancelAnimationFrame(raf)
}
const start = () => {
running = true
run()
}
const run = () => {
raf = requestAnimationFrame(() => {
callback()
if (running) run()
})
}
if (autoStart) start()
return { start, stop }
}
```
```js
const cb = () => console.log('Animation frame fired')
const recorder = recordAnimationFrames(cb) // logs 'Animation frame fired' on each animation frame
recorder.stop() // stops logging
recorder.start() // starts again
const recorder2 = recordAnimationFrames(cb, false) // `start` needs to be explicitly called to begin recording frames
```