// CSS Photo Shuffler v1.0 by
  //   Carl Camera
  //   http://iamacamera.org
  //
  // SetOpacity Function and inpiration from Photo Fade by
  //   Richard Rutter
  //   http://clagnut.com
  //
  // License: Creative Commons Attribution 2.5  License
  //   http://creativecommons.org/licenses/by/2.5/

function photoShufflerLaunch()
  {
          var theimg = document.getElementById(gblPhotoShufflerImgId);
        gblStartImg = theimg.src; // save away to show as final image

        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.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;
}

  var gblPhotoShufflerDivId = "photodiv";
  var gblPhotoShufflerImgId = "photoimg";
  var gblImg = new Array(
    "images/skulptur.jpg",
    "images/deckenmalerei.jpg",
    "images/gemaelde.jpg",
    "images/illusionsmalerei.jpg",
    "images/raumgestaltung.jpg",
    "images/digital-art.jpg",
    "images/illustration.jpg",
    "images/grafik-akt.jpg",
    "images/plueschtier.jpg",
    "images/ei-kunst.jpg",
    "images/moebel-kunst.jpg",
    "images/marionette.jpg",
    "images/schoene-logo.jpg"
    );
  var gblPauseSeconds = 7.25;
  var gblFadeSeconds = .85;
  var gblRotations = 100;

  // End Customization section

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

  window.onload = photoShufflerLaunch;