var old;
var memold;
var subold;



if(document.layers)
{
  window.captureEvents(Event.MOUSEDOWN);
  window.onmousedown=do_out;
}else{
  document.onmouseup=do_out;
}

function sl(x)
{
  if (!x){return true;}
  if(document.layers)
  document.layers[x].visibility="show";
else
  document.all[x].style.visibility="visible";
}

function hl(x)
{
  if (!x){return true;}
  if(document.layers)
    document.layers[x].visibility="hide";
else
  document.all[x].style.visibility="hidden";
}

function do_m(x)
{
  if(!old)
    old=memold;
  if(old!=x)
  {
    sl(x);

    old=x;
  }else
    old="";
}

function do_check(x)
{
  if(!old)
    old=memold;
  if(old && old!=x)
  {
    hl(old);
	sl(x);
	old=x;
    memold=x;
  }
  do_sm();
}

function do_out()
{
	if(old)
      hl(old);
    hls();
	memold=old;
    old="";
	do_sm();
}

function do_sm(x)
{
  if(subold)
  {
    hl(subold);
    subold="";
  }
  if(x)
  {
    sl(x);
    subold=x;
  }
}

function do_layer(x,v)
{
  if (v==0)
  {
  	 sl(x);
  	 return 1;
  }else{
  	 hl(x);
  	 return 0;
  }
}