image-loader.js

import $ from 'jquery'

export default class ImageLoader {
	constructor(images) {
		if ( typeof images === 'string' ) {
			images = [images];
		}

		let promises = images.map(this.loadImage);
		return $.when.apply($, promises);
	}

	loadImage(src) {
		let dfd = new $.Deferred();
		let img = new Image();
		img.src = src;
		img.addEventListener("load", dfd.resolve);
		return dfd.promise();
	}
}