lastBillboard = '1';
maxBillboard = '';
inMotion = 'no';
function load() {
	var gBody = $('portfolioslides');
	k = 0;
	for(var i = 0; i < gBody.childNodes.length; i++) {
		if(gBody.childNodes[i].nodeType == 1) {
			if (gBody.childNodes[i].nodeName == 'DIV') {
				k++;
				id = "portfolio" + k;
				gBody.childNodes[i].setAttribute("id",id);
			}
			maxBillboard = k;
		}
	}
	
}

function nextBillboard(direction) {
	if (inMotion == 'no') {
		inMotion = 'yes'
		if (direction == 'next') {
			
			
			moveBillboard('portfolio'+lastBillboard,1,0,-533);
			
			if (lastBillboard != maxBillboard) { lastBillboard++; }
			else { lastBillboard = '1' }
			$('portfolio'+lastBillboard).style.left='533px';
			moveBillboard('portfolio'+lastBillboard,0,1,0);
		}
		if (direction == 'prev') { 
			
			
			moveBillboard('portfolio'+lastBillboard,1,0,533);
			if (lastBillboard != 1) { lastBillboard = lastBillboard-1; }
			else { lastBillboard = maxBillboard }
			$('portfolio'+lastBillboard).style.left='-533px';
			moveBillboard('portfolio'+lastBillboard,0,1,0);
		}
		setTimeout('inMotion=\'no\'', 800)
	}
}
function moveBillboard(id,startop,endop,direction) {

	 new Effect.Parallel([
		new Effect.Move(id, { sync: true, x: direction, y: 0, mode: 'absolute' }), 
		new Effect.Opacity(id, { sync: true, from: startop, to: endop })
	  ], { 
		duration: .8,
	  });

}