How to change slideshow animation?

Question

JavaScript

There is this html code, with js script. Everything works well, but the slide transition animation is too sharp.. Please help, how to make the animation smooth, what would be from left to right?


function showSlides() {
var i;
var slides = document.getElementsByClassName("mySlides");
var dots = document.getElementsByClassName("dot");
for (i = 0; i < slides.length; i++) {
slides[i].style.display = "none";
}
slideIndex++;
if (slideIndex > slides.length) {slideIndex = 1}
for (i = 0; i < dots.length; i++) {
dots[i].className = dots[i].className.replace(" active", "" );
dots[slideIndex-1].className += "active";
setTimeout(showSlides, 5000); // Change image every 2 seconds

}