function openPop(url,nombre,location,menubar,toolbar,status,resizable,scrollbars,top,left,width,height) {    
	var hWndLinkExterno = window.open(url,nombre,"location="+location+",menubar="+menubar+",toolbar="+toolbar+",status="+status+",resizable="+resizable+",scrollbars="+scrollbars+",top="+top+",left="+left+",width="+width+",height="+height+"");    
	if ((document.window != null) && (!hWndLinkExterno.opener))	hWndLinkExterno.opener = document.window;    
}  

function center(){   
  element = document.getElementById('mainpage');    
  element.style.left = (document.body.clientWidth/2-515)+'px';   
}  
  
function init(){  
menu_show('popup_menu', 'popup_menu_drag', 'null', 'screen-corner', 0, 90,'Menu');   
center();  
  
}  

var menu_dragging = false;  
var menu_target;  
var menu_mouseX;  
var menu_mouseY;  
var menu_mouseposX;  
var menu_mouseposY;  
var menu_oldfunction;  
  
function menu_display(x)  
{  
  var win = window.open();  
  for (var i in x) win.document.write(i+' = '+x[i]+'<br>');  
}  
  
 
  
function menu_mousedown(e)  
{  
  var ie = navigator.appName == "Microsoft Internet Explorer";  
  
  if ( ie && window.event.button != 1) return;  
  if (!ie && e.button            != 0) return;  
  
  menu_dragging = true;  
  menu_target   = this['target'];  
  menu_mouseX   = ie ? window.event.clientX : e.clientX;  
  menu_mouseY   = ie ? window.event.clientY : e.clientY;  
  
  if (ie)  
       menu_oldfunction      = document.onselectstart;  
  else menu_oldfunction      = document.onmousedown;  
  
  if (ie)  
       document.onselectstart = new Function("return false;");  
  else document.onmousedown   = new Function("return false;");  
}  
  
 
  
function menu_mousemove(e)  
{  
  if (!menu_dragging) return;  
  
  var ie      = navigator.appName == "Microsoft Internet Explorer";  
  var element = document.getElementById(menu_target);  
  
  var mouseX = ie ? window.event.clientX : e.clientX;  
  var mouseY = ie ? window.event.clientY : e.clientY;  
  
  element.style.left = (element.offsetLeft+mouseX-menu_mouseX)+'px';  
  element.style.top  = (element.offsetTop +mouseY-menu_mouseY)+'px';  
  
  menu_mouseX = ie ? window.event.clientX : e.clientX;  
  menu_mouseY = ie ? window.event.clientY : e.clientY;  
}  
  
 
  
function menu_mouseup(e)  
{  
  if (!menu_dragging) return;  
  menu_dragging = false;  
  
  var ie      = navigator.appName == "Microsoft Internet Explorer";  
  var element = document.getElementById(menu_target);  
  
  if (ie)  
       document.onselectstart = menu_oldfunction;  
  else document.onmousedown   = menu_oldfunction;  
}  
  
 
  
function menu_exit(e)  
{  
  var ie      = navigator.appName == "Microsoft Internet Explorer";  
  var element = document.getElementById(menu_target);  
  
  menu_mouseup(e);  
  element.style.visibility = 'hidden';  
  element.style.display    = 'none';  
}  
  
  
 
  
function menu_show(id, drag_id, exit_id, position, x, y, position_id)  
{  
    
  //writePopBox(aTitle);  
  element      = document.getElementById(id);  
  drag_element = document.getElementById(drag_id);  
  //exit_element = document.getElementById(exit_id);  
  
  element.style.position   = "relative";  
  element.style.visibility = "visible";  
  element.style.display    = "block";  
  
  if (position == "screen-corner")  
  {  
    element.style.left = (document.documentElement.scrollLeft+x)+'px';  
    element.style.top  = (document.documentElement.scrollTop +y)+'px';  
  }  
  
  if (position == "screen-center")  
  {  
    element.style.left = (document.documentElement.scrollLeft+(document.body.clientWidth -element.clientWidth )/2+x)+'px';  
    element.style.top  = (document.documentElement.scrollTop +(document.body.clientHeight-element.clientHeight)/2+y)+'px';  
  }  
  
  if (position == "mouse-corner")  
  {  
    element.style.left = (document.documentElement.scrollLeft+menu_mouseposX+x)+'px';  
    element.style.top  = (document.documentElement.scrollTop +menu_mouseposY+y)+'px';  
  }  
  
  if (position == "mouse-center")  
  {  
    element.style.left = (document.documentElement.scrollLeft+menu_mouseposX-element.clientWidth /2+x)+'px';  
    element.style.top  = (document.documentElement.scrollTop +menu_mouseposY-element.clientHeight/2+y)+'px';  
  }  
  
  if (position == "element-right" || position == "element-bottom")  
  {  
    var position_element = document.getElementById(position_id);  
  
    for (var p = position_element; p; p = p.offsetParent)  
      if (p.style.position != 'absolute')  
      {  
        x += p.offsetLeft;  
        y += p.offsetTop ;  
      }  
  
    if (position == "element-right" ) x += position_element.clientWidth;  
    if (position == "element-bottom") y += position_element.clientHeight;  
  
    element.style.left = x+'px';  
    element.style.top  = y+'px';  
  }  
  
  drag_element['target']   = id;  
  drag_element.onmousedown = menu_mousedown;  
  
  //exit_element.onclick     = menu_exit;  
}  
  
 
  
function menu_mousepos(e)  
{  
  var ie = navigator.appName == "Microsoft Internet Explorer";  
  
  menu_mouseposX = ie ? window.event.clientX : e.clientX;  
  menu_mouseposY = ie ? window.event.clientY : e.clientY;  
}  
  
 
  
if (navigator.appName == "Microsoft Internet Explorer")  
     document.attachEvent('onmousedown', menu_mousepos);  
else document.addEventListener('mousedown', menu_mousepos, false);  
  
if (navigator.appName == "Microsoft Internet Explorer")  
     document.attachEvent('onmousemove', menu_mousemove);  
else document.addEventListener('mousemove', menu_mousemove, false);  
  
if (navigator.appName == "Microsoft Internet Explorer")  
     document.attachEvent('onmouseup', menu_mouseup);  
else document.addEventListener('mouseup', menu_mouseup, false);