var scrolled, scroll_n, scroll_d;


function set_var(s, n, d){
	scrolled = s;
	scroll_n = n;
	scroll_d = d;
}

function mySwap(id,image){
	if (document.getElementById(id).src != image){
		document.getElementById(id).src = image;		
	}
}

function myshow(who,what){
	target = document.getElementById(who);
	var size = '';
	if (who == 'subjectklein'){
		size = ' width="186" height="10"';
	}
	target.innerHTML = '<img src="'+what+'"'+size+'>'; 
}
function myclear(who){
	target = document.getElementById(who);
	target.innerHTML = ""; 
}
function scrollr(to){
	if (isNaN(scrolled)){
		scrolled = 0;
		window.alert(scrolled+"\n"+scroll_d+"\n"+scroll_n);
	}
	if ((to == 'up')||(to == 'back')){
		scrolled = scrolled +scroll_d;
	} else if ((to == 'down')||(to == 'forward')){
		scrolled = scrolled - scroll_d;
	}
	
	if ((to == 'up')||(to == 'down')){
		document.getElementById('textveld').style.top = scrolled+'px';
		if (scrolled == 0){
			document.getElementById('up1').style.visibility = 'hidden';
			document.getElementById('down1').style.visibility = 'visible';
		} else if (scrolled <= -(scroll_d*scroll_n)){
			document.getElementById('down1').style.visibility = 'hidden';
			document.getElementById('up1').style.visibility = 'visible';
		} else {
			document.getElementById('up1').style.visibility = 'visible';
			document.getElementById('down1').style.visibility = 'visible';
		}
	} else {
		document.getElementById('textveld').style.left = scrolled+'px';
		
		if (scrolled == 0){
			document.getElementById('back').style.visibility = 'hidden';
			document.getElementById('forward').style.visibility = 'visible';
		} else if (scrolled <= -(scroll_d*scroll_n)){
			document.getElementById('forward').style.visibility = 'hidden';
			document.getElementById('back').style.visibility = 'visible';
		} else {
			document.getElementById('back').style.visibility = 'visible';
			document.getElementById('forward').style.visibility = 'visible';
		}
	}	
}
function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}