// Inserts div used for tooltips, hidden with CSS
  document.write('<div id = "tooltip_container"></div>');
  
  tool_tip_library = new Array;
	
  // Displays tooltip when trigger image is hovered over
  // 
  function tooltip_show(element_id, offset_x, offset_y, standard_text, custom_text)
  {
    var tooltip_text = 'not set'
    if (!standard_text){tooltip_text = custom_text;} else {tooltip_text = tool_tip_library[standard_text];}
   
    if (!offset_x){offset_x = 20;}
    if (!offset_y){offset_y = 0;}
    
    var obj = document.getElementById(element_id);
    
    var x = obj.offsetLeft
    var y = obj.offsetTop

    document.getElementById("tooltip_container").innerHTML = tooltip_text;
    
    while (obj.offsetParent)
    {
    	if (obj == document.getElementsByTagName('body')[0])
    	{
    		break;
    	}
    	else
    	{
    		x = x + obj.offsetParent.offsetLeft;
    		y = y + obj.offsetParent.offsetTop;
    		obj = obj.offsetParent;
    	}
    }

    x = x + offset_x;
    y = y + offset_y;
    
    document.getElementById("tooltip_container").style.left = x + "px";
    document.getElementById("tooltip_container").style.top = y + "px";
    document.getElementById("tooltip_container").style.visibility = "visible";
  }

  // Hides tooltip
  function tooltip_hide()
  {
  	document.getElementById("tooltip_container").style.visibility = "hidden";
  }