instante-social/app/javascript/mastodon/scroll.js

31 lines
771 B
JavaScript

const easingOutQuint = (x, t, b, c, d) => c * ((t = t / d - 1) * t * t * t * t + 1) + b;
const scroll = (node, key, target) => {
const startTime = Date.now();
const offset = node[key];
const gap = target - offset;
const duration = 1000;
let interrupt = false;
const step = () => {
const elapsed = Date.now() - startTime;
const percentage = elapsed / duration;
if (percentage > 1 || interrupt) {
return;
}
node[key] = easingOutQuint(0, elapsed, offset, gap, duration);
requestAnimationFrame(step);
};
step();
return () => {
interrupt = true;
};
};
export const scrollRight = (node) => scroll(node, 'scrollLeft', node.scrollWidth);
export const scrollTop = (node) => scroll(node, 'scrollTop', 0);