30 lines
645 B
30 lines
645 B
8 years ago
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const easingOutQuint = (x, t, b, c, d) => c * ((t = t / d - 1) * t * t * t * t + 1) + b;
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const scrollTop = (node) => {
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const startTime = Date.now();
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const offset = node.scrollTop;
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const targetY = -offset;
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const duration = 1000;
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let interrupt = false;
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const step = () => {
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const elapsed = Date.now() - startTime;
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const percentage = elapsed / duration;
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if (percentage > 1 || interrupt) {
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return;
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}
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node.scrollTop = easingOutQuint(0, elapsed, offset, targetY, duration);
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requestAnimationFrame(step);
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};
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step();
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return () => {
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interrupt = true;
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};
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};
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export default scrollTop;
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