function doButtons(index,portraitOrLandscape) {
	var oldImage=document.getElementById('picture').getElementsByTagName('img')[0];
	var newImage=preload[index];
	newImage.alt="Iliopetra";
	var parent = oldImage.parentNode;
	if (portraitOrLandscape==0){
		document.getElementById('picture').className="picportrait";
	} else {
		document.getElementById('picture').className="piclandscape";
	}
	parent.replaceChild(newImage, oldImage);
	var thumbarray=document.getElementById('s_thumb');
	for (var i=0;i<3;i++){
		var nodeObj = thumbarray.getElementsByTagName('img')[i];
		if (i==index) {
			nodeObj.src=s_preload[i].src;
		} else {
			nodeObj.src=t_preload[i].src;
		}
	}
	
	
}