// File JScript

var gblPhotoShufflerDivId = "photodiv";
var gblPhotoShufflerImgId = "photoimg";
var gblPauseSeconds = 4.00;
var gblFadeSeconds = 1.45;
var gblRotations = 100;

var gblDeckSize = gblImg.length;
var gblOpacity = 100;
var gblOnDeck = 0;
var gblStartImg;
var gblImageRotations = gblDeckSize * (gblRotations+1);

window.onload = photoShufflerLaunch;

function photoShufflerLaunch()
{
    var theimg = document.getElementById(gblPhotoShufflerImgId);
    gblStartImg = theimg.src; // save away to show as final image
    document.getElementById(gblPhotoShufflerDivId).style.backgroundRepeat='no-repeat';
    document.getElementById(gblPhotoShufflerDivId).style.backgroundImage='url(' + gblImg[gblOnDeck] + ')';
    setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
}

function photoShufflerFade()
{
    var theimg = document.getElementById(gblPhotoShufflerImgId);
    // determine delta based on number of fade seconds
    // the slower the fade the more increments needed
    var fadeDelta = 100 / (30 * gblFadeSeconds);
    // fade top out to reveal bottom image
    if (gblOpacity < 2*fadeDelta )
    {
        gblOpacity = 100;
        // stop the rotation if we're done
        if (gblImageRotations < 1) return;
        photoShufflerShuffle();
        // pause before next fade
        setTimeout("photoShufflerFade()",gblPauseSeconds*1000);
    }
    else
    {
        gblOpacity -= fadeDelta;
        setOpacity(theimg,gblOpacity);
        setTimeout("photoShufflerFade()",30); // 1/30th of a second
    }
}

function photoShufflerShuffle()
{
    var thediv = document.getElementById(gblPhotoShufflerDivId);
    var theimg = document.getElementById(gblPhotoShufflerImgId);
    // copy div background-image to img.src
    theimg.src = gblImg[gblOnDeck];
    // set img opacity to 100
    setOpacity(theimg,100);
    // shuffle the deck
    gblOnDeck = ++gblOnDeck % gblDeckSize;
    // decrement rotation counter
    if (--gblImageRotations < 1)
    {
        // insert start/final image if we're done
        gblImg[gblOnDeck] = gblStartImg;
    }
    // slide next image underneath
    thediv.style.backgroundRepeat='no-repeat';
    thediv.style.backgroundImage='url(' + gblImg[gblOnDeck] + ')';
}

function setOpacity(obj, opacity) {
    opacity = (opacity == 100)?99.999:opacity;
    // IE/Win
    obj.style.filter = "alpha(opacity:"+opacity+")";
    // Safari<1.2, Konqueror
    obj.style.KHTMLOpacity = opacity/100;
    // Older Mozilla and Firefox
    obj.style.MozOpacity = opacity/100;
    // Safari 1.2, newer Firefox and Mozilla, CSS3
    obj.style.opacity = opacity/100;
}