var NS4DOM = document.layers ? true:false;
var IEDOM = document.all ? true:false;
var W3CDOM = document.getElementById ? true: false;

function getElement(id) {
   if (NS4DOM) ref = "document."+id;
   else if (IEDOM) ref = id;
   else if (W3CDOM) ref = "document.getElementById('"+id+"')";
   var object = eval(ref);
   return object;
}

function scrambleimages()
{
	return 0.5 - Math.random();
}
	var counter2 = 1;
	var images = new Array (
		"photos/home_page/scrolling_images/photo1.jpg",
		"photos/home_page/scrolling_images/photo2.jpg",
		"photos/home_page/scrolling_images/photo3.jpg",
		"photos/home_page/scrolling_images/photo4.jpg",
		"photos/home_page/scrolling_images/photo5.jpg",
		"photos/home_page/scrolling_images/photo6.jpg",
		"photos/home_page/scrolling_images/photo7.jpg",
		"photos/home_page/scrolling_images/photo8.jpg"
		); //ad images
	
	images.sort(scrambleimages); //Scramble the images
	var img_speed = 5000; //Time in ms that each ad is displayed
	
	//script to fade sponsor logos
   function fadeImages()
   {
		var img_1 = getElement("img_1");
		var img_2 = getElement("img_2");
		//The ad images are set to hidden in the CSS before we start showing them

		
		img_1.src = images[0];
		img_2.src = images[1];
		
		restartCycle();
   }
   function restartCycle()
   {
		setTimeout("transitionImage(\"img_1\", 100, 0, 1500)", img_speed);
   }
   function transitionImage(id, opacStart, opacEnd, millisec) 
   {
		//speed for each frame
		var speed = Math.round(millisec / 100);
		var timer = 0;
		var img_1 = getElement("img_1");
		var img_2 = getElement("img_2");
		//determine the direction for the blending, if start and end are the same nothing happens
		if (opacStart > opacEnd) //Fade out to second banner image
		{
			for (i = opacStart; i >= opacEnd; i--) 
			{
				setTimeout("changeOpacity(" + i + ",'" + id + "')",(timer * speed));
				timer++;
			}
			setTimeout("switchImg1()", timer * speed);
			setTimeout("transitionImage(\"img_1\", 0, 100, 1500)", (timer * speed) + img_speed);
		}
		else if (opacStart < opacEnd) //Fade back into the first banner image
		{
			for (i = opacStart; i <= opacEnd; i++)
			{
				setTimeout("changeOpacity(" + i + ",'" + id + "')",(timer * speed));
				timer++;
			}
			setTimeout("switchImg2()", timer * speed);
			setTimeout("restartCycle()", (timer * speed));
		}
	}
	function switchImg1()
	{
		var img_1 = getElement("img_1");
		counter2++;
		if (counter2 == images.length) { counter2 = 0; }
		img_1.src = images[counter2];
	}
	function switchImg2()
	{
		var img_2 = getElement("img_2");
		counter2++;
		if (counter2 == images.length) { counter2 = 0; }
		img_2.src = images[counter2];
	}

	//change the transitionImage for different browsers
	function changeOpacity(transitionImage, id) 
	{
		var object = document.getElementById(id).style;
		object.opacity = (transitionImage / 100);
		object.MozOpacity = (transitionImage / 100);
		object.KhtmlOpacity = (transitionImage / 100);
		object.filter = "alpha(opacity=" + transitionImage + ")";
	}