var counter;
var tempCounter;
var digits = new Array();
var oldDigits = new Array();

function countdown()
{
  if(counter > 0)
    counter--;
  else
    counter = 179;
  tempCounter= counter;
  
  for(var i=3; i>=1; i--)
  {
	digits[i] = tempCounter % 10;
	tempCounter = Math.floor(tempCounter/10);
	if(oldDigits[i] == digits[i])
	  document.getElementById("tick_digit"+i).src = "game/gfx/ui/s"+digits[i]+".gif";
	else
	  document.getElementById("tick_digit"+i).src = "game/gfx/ui/d"+digits[i]+".gif";
	oldDigits[i] = digits[i];
  }
  
  setTimeout('countdown()', 1000);
}

function startCountdown(start)
{
  if(document.getElementById("tick_digit1") == null)
    return;
  
  counter = start;
  for(var i=3; i>=1; i--)
  {
	oldDigits[i] = start % 10;
	start = Math.floor(start/10);
  }
  setTimeout('countdown()', 1000);
}