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Screenshot gallery with HTML and CSS?

I try create a quick prototype where user can see how an animation has looked like in the past. For this I need a screenshot gallery. So far I have in my HTML:
<div id="screenshot"></div>
This function is called based on some events:
function handlePicture() {
console.log("Greetings from server");
var img = document.createElement("img");
img.src = renderer.domElement.toDataURL(); // catching the Three.js scene as image
var src = document.getElementById("screenshot");
src.appendChild(img);
}
This shows the current screenshot. Great! But I want to have 10, 20, 300 or more of them, so that the screenshot is not replaced but a new image is appended next to it.
I would want the animation's timeline to be presented as a gallery, maybe with the help of CSS galleries https://www.w3schools.com/css/tryit.asp?filename=trycss_image_gallery_responsive
I would need help with the next steps. How could each function call save renderer.domElement.toDataURL(); as a new image and create an element for it? I'm confused if I should make a new div for every image or put them all under div "screenshot". Many thanks!

I have set up a pen to demonstrate creating an image element with a button.
renderer.domElement.toDataURL() Is an async function so you would need to wrap it in a callback function.
var imgBtn = document.getElementById("addImage");
document.addEventListener("click", function(){
var newImage = document.createElement("img")
document.body.appendChild(newImage)
newImage.setAttribute("src",
"https://via.placeholder.com/150/0000FF/808080%20?
Text=Digital.com%20C/O%20https://placeholder.com/)")})
https://codepen.io/sijbc/pen/MWJeveL

How to make a grid of interactive elements?

I'm trying to create a portfolio website that resembles this, a full-page grid of images that change when you hover over them... (another example, the third screen!)
And currently I have a crude solution that looks like:
<img src="1.png" id="img" swap="2.png"/>
// then in JS...
$("#img").hover(function(){
var _this = $(this);
var current = _this.attr("src");
var swap = _this.attr("swap");
_this.attr('src',swap).attr('swap',current);
}); //
code credit
But this isn't a very scaleable solution and other than having 1000 images, each with their own unique ID which is identified so the src can be toggled, I'm not sure what to do -- plus I don't know how this would react to different display sizes/screen cut-offs. And while background-image in CSS tiles nicely, it doesn't allow interactivity... unless maybe you had a JS script track cursor position(?)
!! This is my very first project, any help would be appreciated :) (Codecademy is a very sheltered learning environment........)

you don't have to use ids and create a handler for every image.
this will apply to every image CURRENTLY on the page:
$("img").hover(function(){
var _this = $(this);
var current = _this.attr("src");
var swap = _this.attr("swap");
_this.attr('src',swap).attr('swap',current);
});
and this will react to every image, even images added after the page is loaded:
$(document).on('hover', 'img', function () {
var _this = $(this);
var current = _this.attr("src");
var swap = _this.attr("swap");
_this.attr('src',swap).attr('swap',current);
});
To account for screen sizes and your other concerns, you'd need to either set a fixed width and height on your images, or make sure all your images are of similar resolution.
You could do this with backgrounds as well by creating a grid of divs then change the background of the div on hover, similar to the above handlers.

Is there a better way to handle loading arrays of images?

I have groups of related images that I would like to be able to change (but position in the same div) by clicking on different radio buttons.
Currently I am using arrays to handle the html,
var marketingImages = [image1HTML, image2HTML, image3HTML, image4HTML];
var salaryImages = [image1HTML, image2HTML, image3HTML, image4HTML];
And when a relevant radio button is clicked, a function runs to clear the html in the div (of possible previous images), and load the new images using .append.
$(document).ready(function() {
$("#marketing, #salary").click(leed);
function leed() {
$("#portfolio-images").html("");
if ($("#marketing").is(':checked')) {
var portfolioArray = marketingImages;
} else if ($("#salary").is(':checked')) {
var portfolioArray = salaryImages;
}
for (var i=0; i<portfolioArray.length; i++) {
$("#portfolio-images").append(portfolioArray[i]);
}
...
}
It seems to work well, but being a noob though I have to wonder if there's a better way to handle this. Technically these images are just thumbnails (that can be clicked on to load larger Lightbox versions), but I'm unsure of how well that would "really" load for someone.
Does somebody know if there's a better way to handle loading groups of images? Thanks.

Rendering custom photo set using tumblr JSON

I am creating this custom theme www.designislikethis.tumblr.com, which uses the jQuery Masonry and the Slider plugins. In creating this theme I wanted to create my own photoset slideshow instead of messing around with the default Flash-based one.
I started by pulling the images from the JSON of each photoset post by the post's ID using JS and jQuery.
I then rendered these images onto my frontpage in a special div that is linked to a minimal jQuery slideshow plugin, so each image fades in and out.
The code I use to pull/render for each photoset post is as follows:
function photoSet() {
$('.photoset').each(function () {
var postID = $(this).attr('id');
var that = $(this);
$.getJSON("http://designislikethis.tumblr.com/api/read/json?id="+postID+"&callback=?",
function(data) {
var postPhotos = data["posts"][0]["photos"];
var postPermalink = data["posts"][0];
for(var i = 0; i<postPhotos.length; i++)
{
var photo250 = new Image();
photo250.src = postPhotos[i]['photo-url-250'];
postLink = postPermalink["url-with-slug"];
var setClass = ".photoset"+ i;
var imgClass = ".img"+ i;
$(that).find('.slide').append('<a class="'+ setClass +'" href="'+postLink+'"><img class="'+ imgClass +'" src="' +photo250.src+ '"/></a>');
}
});
});
}
Now my problem lies in that all the other elements on my tumblr index page are not rendered with JSON, so they load faster. By the time my photo set renders it's divs are unproportional to everything that has loaded around it, and so the image slider wont kick in and you are left with a mess of rendered images.
What's most annoying about this problem is that some times it works fine, and others it's a mess, depending on how fast the page loads, or if you have the website already cached in your browser.
To see the extent of my Javascript and how I am calling this photoset funciton see here:
http://helloauan.com/apps/DILTtheme/utils.js
I know it's a little messy, for I am new to all of this. :)
Thanks.

I don't know if it will help, but you could try the following:
If the images are the same size and you know that size set the ".slide" div to that;
Try preloading the images and only starting the slide show when they are loaded. e.g using a preload plug-in.
and making use of the "callback" function.

how to preload large size image?

i have certain links, on mouse over of those links I am changing <div> background image
jQuery I have used is-
function imgchange()
{
$('.smenu li').mouseover( function(){
var src = $(this).find('a').attr('href');
$('.hbg').css('background-image', 'url(' + src + ')');
$(this).find('hbg').attr('title', 'my tootip info');
});
}
It is working fine but the problem is when I running it on server images takes 3-4 sec to be changed on change, but the second time I do mouse over images are getting changed instantly, I think this is because of browser stored images in cache. So I added one javascript to preload images on page onLoad() ivent -
<script language = "JavaScript">
function preloader()
{
heavyImage = new Image();
heavyImage.src = "images/soluinfo1.jpg";
heavyImage.src = "images/soluinfo2.jpg";
heavyImage.src = "images/soluinfo3.jpg";
heavyImage.src = "images/soluinfo4.jpg";
heavyImage.src = "images/soluinfo5.jpg";
heavyImage.src = "images/soluinfo6.jpg";
heavyImage.src = "images/soluinfo7.jpg";
}
</script>
<body onLoad="javascript:preloader()">
but this script has not solved my problem.what should I do?

#Richard's answer (sprites) is probably the best one for what you are after, but the reason your code is not working is that in most browsers, only the last heavyImage.src="" is given enough time to actually register with the browser as an actual request. You're creating only one Image object setting and resetting the .src attribute faster than the browser can request the files (I think modern JavaScript engines take the added step of removing all the intermediate .src statements specifically because of this).
There are a couple of ways to fix this. The easiest is to create multiple Image objects, one for each image. And the easiest way to do that is through something like this:
<script type="text/javascript">
function preloader()
{
function doPreload(strImagePath)
{
var heavyImage = new Image();
heavyImage.src = strImagePath;
}
var arrImages = ["images/soluinfo1.jpg","images/soluinfo2.jpg","images/soluinfo3.jpg","images/soluinfo4.jpg","images/soluinfo5.jpg","images/soluinfo6.jpg","images/soluinfo7.jpg"];
for (var i = 0; i < arrImages.length; i++) {
doPreload(arrImages[i]);
}
}
</script>
By putting the heavyImage variable inside its own function (remember to use the var keyword), you're ensuring that the Image object exists inside its own dedicated scope.
Another way to do this is to attach a "load" event listener to a single heavyImage. Every time the image finishes loading, go fetch the next image. The disadvantage to this method is that your images will be loaded one at a time (bad for navigation images, but great for, say, and image gallery), whereas the first technique will fetch the images in parallel (typicallly four at a time).

You might find it easier to change your approach and use CSS sprites (and another article). Then you would just have one image referenced, and you use CSS to set which part of that image gets shown in which scenario.
This assumes that the images you're using are under your control and you can use an image editor to combine them into one large image.