function $() {
  var elements = new Array();

  for (var i = 0; i < arguments.length; i++) {
    var element = arguments[i];
    if (typeof element == 'string')
      element = document.getElementById(element);

    if (arguments.length == 1) 
      return element;

    elements.push(element);
  }

  return elements;
}

function setCookie(c_name,value,expiredays)
{
	var exdate=new Date();
	exdate.setDate(exdate.getDate()+expiredays);
	document.cookie=c_name+ "=" +escape(value)+
		((expiredays==null) ? "" : ";expires="+exdate.toGMTString());
}

function getCookie(c_name)
{
	if (document.cookie.length>0)
	{
		c_start=document.cookie.indexOf(c_name + "=");
		if (c_start!=-1)
		{
			c_start=c_start + c_name.length+1;
			c_end=document.cookie.indexOf(";",c_start);
			if (c_end==-1) c_end=document.cookie.length;
			return unescape(document.cookie.substring(c_start,c_end));
		}
	}
	return "";
}

var blurValue = 100;
var blurEvent;
function blurPictures()
{
	blurValue = blurValue - 4;

	$('picalt').style.opacity = ((100-blurValue)/100);
	$('picalt').style.filter = 	"alpha(opacity=" + (100-blurValue) + ")";
	if(blurValue==0)	swapImages(); // na koniec zmiana obrazka na następny
	
}

function timeoutTick()
{
	clearInterval(blurEvent);
	blurEvent = setInterval("blurPictures();", 20);
}

var arrPic = new Array('pic_oprogramowanie_dedykowane.jpg', 'pic_business_technology_solutions.jpg', 
			'pic_systemy_na_zamowienie.jpg', 'pic_astcon_dedicated_tailor_made_systems.jpg', 
			'pic_astcon_it_solutions_biznes_technologia.jpg', 'pic_oprogramowanie_na_zamowienie.jpg', 
			'pic_system_dedykowany.jpg', 'pic_system_na_zamowienie.jpg', 'pic_systemy_dedykowane.jpg');
function swapImages()
{
	clearInterval(blurEvent);
	blurValue = 100;
	
	rand  = rand2;
	rand2 = (rand+1<arrPic.length ? rand+1 : 0);
	
	// ładujemy aktualny obrazek do głównej ramki i wyświetlamy go
	$('pic').style.backgroundImage = "url(img/" + arrPic[rand] + ")";
	$('pic').style.opacity = 	1;
	$('pic').style.filter = 	"alpha(opacity=" + 100 + ")";
	
	// ukrywamy obrazek nieaktualny, i pobieramy do niego nowy pikczer
	$('picalt').style.opacity = 0;
	$('picalt').style.filter = 	"alpha(opacity=" + 0 + ")";
	$('picalt').style.backgroundImage = "url(img/" + arrPic[rand2] + ")";
		

}
function preloadImages()
{
	var preloadImage = new Array();
	for(var i=0; i<arrPic.length; i++)
	{
		preloadImage[i] = new Image();
		preloadImage[i].src = arrPic[i];
	}
}

setInterval("timeoutTick();", 6000);
preloadImages();