var sponsorImage = Array();
var sponsor_url = Array();
var current_image = 0;

function add_image(xi_locatie, xi_titel, xi_nav_url)
{

	if(sponsorImage[0] == null)
	{
		var i = 0;
	}
else
	{
		var i = sponsorImage.length ++;
	}

	sponsorImage[i] = new Image();
	sponsorImage[i].src = xi_locatie;
	sponsorImage[i].title = xi_titel;
	sponsor_url[i] = xi_nav_url;
}

function swap_image()
{

	//eerst testen of er wel images in de array zitten
	if (sponsorImage[0] != null)
	{
		//met maar 1 plaatje hoef je geen random te doen
		var random_image = 0;
		if (sponsorImage.length > 1) 
		{

			//willekeurig nummer zoeken
			random_image = Math.round(Math.random() * sponsorImage.length);
			if (random_image == sponsorImage.length)
			{
				random_image --
			}

			//net zo lang doorgaan tot een ander nummer gevonden is
			while (random_image == current_image)
			{
				random_image = Math.round(Math.random() * sponsorImage.length);
				if (random_image == sponsorImage.length)
				{
					random_image --
				}
			}
		}
		//alert(random_image);
		window.document.images['img_sponsor'].src=sponsorImage[random_image].src;
		window.document.images['img_sponsor'].title=sponsorImage[random_image].title;
		current_image = random_image;
	}
}
function nav_sponsor()

{
	window.open(sponsor_url[current_image],'_blank');
}