var iNumImagesToPreload = 0;
var iNumPreloadedImages = 0;

function AddPreLoad (sURL)
{

    iNumImagesToPreload++;

    var objImage = new Image();     
    objImage.onLoad = imagesLoaded();
    objImage.src = sURL;
    
  
}

function imagesLoaded()
{
    iNumPreloadedImages += 1;
}

function AllPreImagesLoaded ()
{
    return (iNumImagesToPreload == iNumPreloadedImages);
}