/* Teil des Slideshow-Moduls des CMS */

/* Das Script erzeugt Überblendungen zwischen Bildern */

var slideshow_imgs = new Array();
var slideshow_durations = new Array();
var slideshow_alpha_step = 5;
var slideshow_blend_duration = 1000;


function slideshow_init(id, imgs, durations)
{
  var div = document.getElementById("slideshow" + id);
  slideshow_imgs[id] = Array(document.getElementById("slideshow" + id + "_img"));
  for(var i = 1; i < imgs.length; i++)
  {
    var img = document.createElement("img");
    img.src = imgs[i];
    img.style.visibility = "hidden";
    div.appendChild(img);
    slideshow_imgs[id].push(img);
  }

  slideshow_durations[id] = durations;

  if (slideshow_imgs[id].length > 1) setTimeout("slideshow_step(" + id + ", 0, 1, " + (100 - slideshow_alpha_step) + ")", slideshow_durations[id][0] * 1000);
}

function slideshow_step(id, img1, img2, alpha)
{
  slideshow_imgs[id][img2].style.opacity = (100 - alpha) * 0.01;
  slideshow_imgs[id][img2].style.filter = "alpha(opacity=" + (100 - alpha) + ")";
  if (alpha == 100 - slideshow_alpha_step) slideshow_imgs[id][img2].style.visibility = "visible";

  if (alpha == 0) slideshow_imgs[id][img1].style.visibility = "hidden";
  else
  {
    slideshow_imgs[id][img1].style.opacity = alpha * 0.01;
    slideshow_imgs[id][img1].style.filter = "alpha(opacity=" + alpha + ")";
  }

  if(alpha == 0)
  {
    img1 = img2;
    if (++img2 == slideshow_imgs[id].length) img2 = 0;
    setTimeout("slideshow_step(" + id + ", " + img1 + ", " + img2 + ", " + (100 - slideshow_alpha_step) + ")", slideshow_durations[id][img1] * 1000);
  }
  else
  {
    setTimeout("slideshow_step(" + id + ", " + img1 + ", " + img2 + ", " + (alpha - slideshow_alpha_step) + ")", slideshow_blend_duration / (100 / slideshow_alpha_step));
  }
}