hnsalert/templates/assets/js/bold-and-dark.js

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JavaScript
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2023-12-11 15:28:20 +11:00
(function() {
"use strict"; // Start of use strict
function initParallax() {
if (!('requestAnimationFrame' in window)) return;
if (/Mobile|Android/.test(navigator.userAgent)) return;
var parallaxItems = document.querySelectorAll('[data-bss-parallax]');
if (!parallaxItems.length) return;
var defaultSpeed = 0.5;
var visible = [];
var scheduled;
window.addEventListener('scroll', scroll);
window.addEventListener('resize', scroll);
scroll();
function scroll() {
visible.length = 0;
for (var i = 0; i < parallaxItems.length; i++) {
var rect = parallaxItems[i].getBoundingClientRect();
var speed = parseFloat(parallaxItems[i].getAttribute('data-bss-parallax-speed'), 10) || defaultSpeed;
if (rect.bottom > 0 && rect.top < window.innerHeight) {
visible.push({
speed: speed,
node: parallaxItems[i]
});
}
}
cancelAnimationFrame(scheduled);
if (visible.length) {
scheduled = requestAnimationFrame(update);
}
}
function update() {
for (var i = 0; i < visible.length; i++) {
var node = visible[i].node;
var speed = visible[i].speed;
node.style.transform = 'translate3d(0, ' + (-window.scrollY * speed) + 'px, 0)';
}
}
}
initParallax();
})(); // End of use strict