function opacity(id, opacStart, opacEnd, millisec) {
	//snelheid van elke frame
	var speed = Math.round(millisec / 1000);
	var timer = 0;

	//animatie
	for(i = opacStart; i <= opacEnd; i++) {
	setTimeout("changeOpac(" + i + ",'" + id + "')",(timer * speed));
	timer++;
	}
}  
  
//Opacity voor verschillende browsers
function changeOpac(opacity, id) {
	var object = document.getElementById(id).style;
	object.opacity = (opacity / 99);
	object.MozOpacity = (opacity / 99);
	object.KhtmlOpacity = (opacity / 99);
	object.filter = "alpha(opacity=" + opacity + ")";
}

// Opacity  initialiseren
function shiftOpacity(id, millisec) {
	opacity(id, 0, 60, millisec);
}

function switchPopUp(div_id, popup, img, url, titel, breedte, hoogte) {
	document.img_overlay.src = 'sbh/images/'+url;
	shiftOpacity('pop_up_screen', 1000);
	id = document.getElementById(div_id);
	id.style.display = (id.style.display == 'none') ? 'block' : 'none';
	document.getElementById('popup_titel').innerHTML = titel;
	
	var scrollHeight = document.documentElement['scrollHeight'];
	var clientHeight = document.documentElement['clientHeight'];
	
	if (breedte < hoogte) { 
		var height = scrollHeight+40;
	} else {
		if (clientHeight < scrollHeight) {
			var height = scrollHeight+20;
		} else {
			var height = scrollHeight+(clientHeight-scrollHeight);
		}
	}
	document.getElementById(popup).style.height = height+'px';	
}

function letterGrootteClick()
{
	if (getCookie('FontSizeSBH')) {
		if (getCookie('FontSizeSBH') == 'inhoud_size') {
			setCookie("FontSizeSBH", "inhoud", 1);
			//document.getElementById('inhoud_size').id = "inhoud";
		} else {
			setCookie("FontSizeSBH", "inhoud_size", 1);
			//document.getElementById('inhoud').id = "inhoud_size";
		}
    } else {
        setCookie("FontSizeSBH", "inhoud_size", 1);
		//document.getElementById('inhoud').id = "inhoud_size";
	}
	location.reload(true);
}

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 ""
}