var imgButtons = new Array();


function preloadImages()
{
  var startIndex = 0;
  if (!document.preloadedImages)
  {
    document.preloadedImages = new Array();
  }
  else
  {
    startIndex = document.preloadedImages.length;
  }

  var testValue = document.preloadedImages.length + preloadImages.arguments.length;
  for (var i = startIndex; i < testValue; i++)
  {
    document.preloadedImages[i] = new Image();
    document.preloadedImages[i].src = preloadImages.arguments[i];
  }
}


function openWindow(strPage)
{
  open(strPage);
}


function registerButton(strID, imgButton)
{
  imgButtons[strID] = imgButton;
}


function activateButton(strID)
{
  imgButtons[strID].src = "Images/Interface/" + strID + "-Purple.gif";
}


function highlightButton(strID)
{
  imgButtons[strID].src = "Images/Interface/" + strID + "-Yellow.gif";
}


function normaliseButton(strID)
{
  imgButtons[strID].src = "Images/Interface/" + strID + "-Terracotta.gif";
}