var offsetfrommouse=[15,15]; //image x,y offsets from cursor position in pixels. Enter 0,0 for no offset
var currentimageheight = 253;	// maximum image size.
var maximagewidth = 380;

if (document.getElementById || document.all){
	document.write('<div id="imgpopup">');
	document.write('</div>');
}

function gettrailobj(){
	if (document.getElementById)
		return document.getElementById("imgpopup").style
	else if (document.all)
		return document.all.trailimagid.style
}

function gettrailobjnostyle(){
	if (document.getElementById)
		return document.getElementById("imgpopup")
	else if (document.all)
		return document.all.trailimagid
}


function truebody(){
	return (!window.opera && document.compatMode && document.compatMode!="BackCompat")? document.documentElement : document.body
}

function showtrail(imagename,description,width,height){
	if (width > maximagewidth) {
		width = maximagewidth;
	}

	if (height > 0){
		currentimageheight = height;
	}

	document.onmousemove=followmouse;

	newHTML = '<div class="background">';
	newHTML = newHTML + '<div><img src="' + imagename + '" width="' + width + '" border="0"></div>';
	
	if (description != "") {
		newHTML = newHTML + '<div class="onderschrift">' + description + '</div>';
	}
		
	newHTML = newHTML + '</div>';
	gettrailobjnostyle().innerHTML = newHTML;
	gettrailobj().display="inline";
}


function hidetrail(){
	gettrailobj().innerHTML = " ";
	gettrailobj().display="none"
	document.onmousemove=""
	gettrailobj().left="-500px"

}

function followmouse(e){

	var xcoord=offsetfrommouse[0]
	var ycoord=offsetfrommouse[1]

	var docwidth=document.all? truebody().scrollLeft+truebody().clientWidth : pageXOffset+window.innerWidth-15
	var docheight=document.all? Math.min(truebody().scrollHeight, truebody().clientHeight) : Math.min(window.innerHeight)

	if (typeof e != "undefined"){
		if (docwidth - e.pageX < 420){
			xcoord = e.pageX - xcoord - 400; // Move to the left side of the cursor
		} else {
			xcoord += e.pageX;
		}
		
		if (docheight - e.pageY < (currentimageheight + 60)){
			ycoord += e.pageY - Math.max(0,(60 + currentimageheight + e.pageY - docheight - truebody().scrollTop));
		} else {
			ycoord += e.pageY;
		}

	} else if (typeof window.event != "undefined"){
		//alert(document.getElementById("imgpopup").offsetHeight);
		if (docwidth - event.clientX < 420){
			xcoord = event.clientX + truebody().scrollLeft - xcoord - 400; // Move to the left side of the cursor
		} else {
			xcoord += truebody().scrollLeft+event.clientX
		}
		if (docheight - event.clientY < (currentimageheight + 60)){
			ycoord += event.clientY + truebody().scrollTop - Math.max(0,(60 + currentimageheight + event.clientY - docheight));
		} else {
			ycoord += truebody().scrollTop + event.clientY;
		}
	}

	var docwidth=document.all? truebody().scrollLeft+truebody().clientWidth : pageXOffset+window.innerWidth-15
	var docheight=document.all? Math.max(truebody().scrollHeight, truebody().clientHeight) : Math.max(document.body.offsetHeight, window.innerHeight)
		if(ycoord < 0) { ycoord = ycoord*-1; }
	gettrailobj().left=xcoord+"px"
	gettrailobj().top=ycoord+"px"

}