Image Pre-loader

sample.js

// Note: pre-fetching all images is dumb! It wastes bandwidth on content that "might" be viewed
//       Instead: Look up something called "Lazy Loading"

(function (queue, mapper) {
	mapper = mapper || function (obj) { return obj; };
	var image = new Image(), index = 0;
	image.onload = function () {
		if (index < queue.length) image.src = mapper( queue[index++] );
	};
	image.onerror = function (e) {
		console.log(e);
		image.onload();
	};
	image.onload();
})( ['img/img1.png', 'img/img2.png', 'img/img3.png'], function (obj) { return obj; } );