function enableSwitcher() {
	for (i=0; i < aryImages.length; i++) {
		var preload = new Image();
		preload.src = aryImages[i];
	}
}

function swap(imgIndex, imgTarget, subtitle) {
	document.getElementById(imgTarget).src = aryImages[imgIndex];
	document.getElementById('subtitle').innerHTML = subtitle;
	
	var thumbnails = getElementsByClassName2('thumbnail');
	for (i = 0; i < thumbnails.length; i++) {
      thumbnails[i].className = "thumbnail";
  }
  
  var thumbnailId = "thumbnail_" + imgIndex;
  document.getElementById(thumbnailId).className = "thumbnail active";
}

function getElementsByClassName2(classname) {
    node = document.getElementsByTagName("body")[0];
    var a = [];
    var re = new RegExp('\\b' + classname + '\\b');
    var els = node.getElementsByTagName("*");
    for(var i=0,j=els.length; i<j; i++)
        if(re.test(els[i].className))
            a.push(els[i]);
    return a;
 }