21 lines
524 B
JavaScript
21 lines
524 B
JavaScript
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// Sometimes we want to queue multiple requestAnimationFrames but only run the last one.
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// It's tedious to do this using cancelAnimationFrame, so this is a utility to throttle
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// a timer such that it only runs the last callback when it fires.
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export const throttleTimer = timer => {
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let queuedCallback
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const flush = () => {
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const callback = queuedCallback
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queuedCallback = null
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callback()
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}
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return callback => {
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if (!queuedCallback) {
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timer(flush)
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}
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queuedCallback = callback
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}
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}
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