Scroll on hover for carousel

by Vladimir Kutepov

HTML

<div class="outer">
  <div class="inner">
    Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
  </div>
</div>

CSS

body {
  margin: 100px;
}
.outer {
  border: 1px solid black;
  overflow-x: scroll;
  font: 16px/20px Helvetica Neue, Helvetica, Arial, sans-serif;
}

.inner {
  background: linear-gradient(to right, red, orange, yellow, green, blue, violet, red);
  padding: 40px;
  width: 4000px;
  color: #fff;
}

JavaScript

const el = document.getElementsByClassName('outer')[0];
el.addEventListener('mousemove', handleMouseMove);
el.addEventListener('mouseout', handleMouseOut);

function handleMouseMove(e) {
  const rect = e.currentTarget.getBoundingClientRect();
  const x = e.pageX - (window.pageXOffset + rect.left);
  const position = x / rect.width;
  let speed = 0;
  if (position < 0.25) speed = 0.25 - position;
  if (position > 0.75) speed = position - 0.75;
  console.log(speed);
}

function handleMouseOut(e) {
	// stop animation
}

function animate(draw, duration) {
  const start = performance.now();
  requestAnimationFrame(function animate(time) {
    const timePassed = time - start;
    if (timePassed > duration) timePassed = duration;
    draw(timePassed);
    if (timePassed < duration) {
      requestAnimationFrame(animate);
    }
  });
}