Uses jQuery's new Deferred object to help with image loading

preloader.js

var preloadImages = function(srcs) {
    var dfd, i, img, l, p, promises;
    jQuery.whenArray = function(array) {
      return jQuery.when.apply(this, array);
    };
    dfd = $.Deferred();
    promises = [];
    img;
    l;
    p;
    if (!$.isArray(srcs)) {
      srcs = [srcs];
    }
  
    l = srcs.length;
    i = 0;
    while (i < l) {
      p = $.Deferred();
      img = $('<img />');
      img.load(p.resolve);
      img.error(p.resolve);
      promises.push(p);
      img.get(0).src = srcs[i].src;
      ++i;
    }
    $.whenArray(promises).done(dfd.resolve);
    return dfd.promise();
  }