function xstooltip_findPosX(obj){
	var curleft = 0;
	if (obj.offsetParent){
		while (obj.offsetParent){
			curleft += obj.offsetLeft
			obj = obj.offsetParent;
		}
	}else if (obj.x){
		curleft += obj.x;
	}
	return curleft;
}

function xstooltip_findPosY(obj) {
	var curtop = 0;
	if (obj.offsetParent){
		while (obj.offsetParent){
			curtop += obj.offsetTop
			obj = obj.offsetParent;
		}
	}else if (obj.y){
		curtop += obj.y;
	}
	return curtop;
}

function xstooltip_show(tooltipId, parentId, posX, posY){
	it = document.getElementById(tooltipId);
	if ((it.style.top == '' || parseInt(it.style.top) == 0) 
	 && (it.style.left == '' || parseInt(it.style.left) == 0)){
		// need to fixate default size (MSIE problem)
		it.style.width = it.offsetWidth + 'px';
		it.style.height = it.offsetHeight + 'px';
		
		img = document.getElementById(parentId); 
		
		// if tooltip is too wide, shift left to be within parent 
		if (posX + it.offsetWidth > img.offsetWidth) posX = img.offsetWidth - it.offsetWidth;
		if (posX < 0 ) posX = 0; 
		
		x = xstooltip_findPosX(img) + posX;
		y = xstooltip_findPosY(img) + posY;
		
		it.style.top = y + 'px';
		it.style.left = x + 'px';
	}
	it.style.visibility = 'visible'; 
}

function xstooltip_hide(id){
	it = document.getElementById(id); 
	it.style.visibility = 'hidden'; 
}