mastodon/app/javascript/flavours/glitch/util/scroll.js
ThibG 46829e009e [Glitch] Use ScrollToOptions for smooth scrolling if supported
Port 84ff393842 to glitch-soc

Signed-off-by: Thibaut Girka <thib@sitedethib.com>
2019-06-30 11:01:01 +02:00

33 lines
1,020 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;
};
};
const isScrollBehaviorSupported = 'scrollBehavior' in document.documentElement.style;
export const scrollRight = (node, position) => isScrollBehaviorSupported ? node.scrollTo({ left: position, behavior: 'smooth' }) : scroll(node, 'scrollLeft', position);
export const scrollTop = (node) => isScrollBehaviorSupported ? node.scrollTo({ top: 0, behavior: 'smooth' }) : scroll(node, 'scrollTop', 0);