var imgNum = 1;
var slides;

function start()
{
	clearInterval(slides);
	slides = setInterval("toggleSite()", 5000);
}

function stop()
{
	clearInterval(slides);
	document.getElementById('leftArrow').style.display = 'block';
	document.getElementById('rightArrow').style.display = 'block';
}

function go()
{
	start();
	document.getElementById('leftArrow').style.display = 'none';
	document.getElementById('rightArrow').style.display = 'none';
}

function back()
{
	if (imgNum == 1)
		imgNum = 3;  //Set this value to your number of photos -1. ( Ex. 8 photos, imgNum = 7 )
	else
		imgNum = imgNum - 2;
		
	toggleSite();
}

function forward()
{
	toggleSite();
}

function toggleSite()
{
	fadeElement('slideshow', 100, 0, 300);
	setTimeout
	(
		function()
		{
			document.getElementById('slideshow').innerHTML =  document.getElementById('image'+imgNum).innerHTML;
			fadeElement('slideshow', 0, 100, 300);
		}
		,301);
	imgNum++;
	if (imgNum > 4) // Set this number to your number of photos. ( Ex. 8 photos, if (imgNum > 8) )
		imgNum = 1;
}

function fadeElement(eID,fStart,fStop,fDur)
{
	var fSpeed = Math.round(fDur / 100);
	var fTimer = 0;
	if (fStart<fStop)
	{
		for(var i=fStart; i<=fStop; i++)
		{
			setTimeout("setOpacity('"+eID+"',"+i+")",fTimer*fSpeed);
			fTimer++;
		}
		return;
	}
	for(var i=fStart; i>=fStop; i--)
	{
		setTimeout("setOpacity('"+eID+"',"+i+")",fTimer*fSpeed);
		fTimer++;
	}
}

function setOpacity(eID, opac)
{
	var eStyle = document.getElementById(eID).style;
	eStyle.opacity = opac / 100;
	eStyle.filter = 'alpha(opacity='+opac+')';
	eStyle.MozOpacity = opac / 100;
}