// swap the imgTagID src between imageFile1 and imageFile2
function nyx_swapImage(imgTagID, imageFile1, imageFile2, documentObject)
{
  documentObject = documentObject || document;
  
  var image1 = new Image();
  var image2 = new Image();
  
  image1.src = imageFile1;
  image2.src = imageFile2;
  
  if (documentObject.getElementById(imgTagID) == null)
    return;
  
  
  if (documentObject.getElementById(imgTagID).src == image1.src)
    documentObject.getElementById(imgTagID).src = image2.src;
  else
    documentObject.getElementById(imgTagID).src = image1.src;
}

// swap the imgTagID src between imageFile1 and imageFile2
function nyx_swapBgImage(objTagID, imageFile1, imageFile2, documentObject)
{
  documentObject = documentObject || document;
  
  var image1 = new Image();
  var image2 = new Image();
  
  image1.src = imageFile1;
  image2.src = imageFile2;
  
  if (documentObject.getElementById(objTagID) == null)
    return;
  
  if (documentObject.getElementById(objTagID).style.backgroundImage == image1.src)
    documentObject.getElementById(objTagID).style.backgroundImage = "url('" + image2.src + "')";
  else
    documentObject.getElementById(objTagID).style.backgroundImage = "url('" + image1.src + "')";
}

// swap the imgTagID src between imageFile1 and imageFile2
function nyx_swapObjDisplay(objTagID, documentObject)
{
  documentObject = documentObject || document;
  
  if (documentObject.getElementById(objTagID) == null)
    return;
  
  if (documentObject.getElementById(objTagID).style.display == 'block')
    documentObject.getElementById(objTagID).style.display = "none";
  else
    documentObject.getElementById(objTagID).style.display = "block";
}