function isVisible (ele) {
const { top, bottom } = ele.getBoundingClientRect();
const vHeight = (window.innerHeight || document.documentElement.clientHeight);
return (
(top > 0 || bottom > 0) &&
top < vHeight
);
}function isInViewport(element) {
const rect = element.getBoundingClientRect();
return (
rect.top >= 0 &&
rect.left >= 0 &&
rect.bottom <= ((window.innerHeight + rect.height) || document.documentElement.clientHeight) &&
rect.right <= (window.innerWidth || document.documentElement.clientWidth)
);
}
//optimized from the stackOverflow answer to account
//for element heights and widths (in vertical/horizontal scrolling)