// Browser Slide-Show script. With image cross fade effect for those browsers
// that support it.
// Script copyright (C) 2004-2008 www.cryer.co.uk.
// Script is free to use provided this copyright header is included.
var FadeDurationMS=500;
function SetOpacity(object,opacityPct)
{
  // IE.
  object.style.filter = 'alpha(opacity=' + opacityPct + ')';
  // Old mozilla and firefox
  object.style.MozOpacity = opacityPct/100;
  // Everything else.
  object.style.opacity = opacityPct/100;
}
function ChangeOpacity(id,msDuration,msStart,fromO,toO)
{
  var element=document.getElementById(id);
  var msNow = (new Date()).getTime();
  var opacity = fromO + (toO - fromO) * (msNow - msStart) / msDuration;
  if (opacity>=100)
  {
    SetOpacity(element,100);
    element.timer = undefined;
  }
  else if (opacity <= 0)
  {
    SetOpacity(element,0);
    element.timer = undefined;
  }
  else
  {
    SetOpacity(element,opacity);
    element.timer = window.setTimeout("ChangeOpacity('" + id + "'," + msDuration + "," + msStart + "," + fromO + "," + toO + ")",10);
  }
}
function FadeInImage(foregroundID,newImage,backgroundID)
{
  var foreground=document.getElementById(foregroundID);
  if (foreground.timer) window.clearTimeout(foreground.timer);
  if (backgroundID)
  {
    var background=document.getElementById(backgroundID);
    if (background)
    {
      if (background.src)
      {
        foreground.src = background.src;
        SetOpacity(foreground,100);
      }
      background.src = newImage;
      background.style.backgroundImage = 'url(' + newImage + ')';
      background.style.backgroundRepeat = 'no-repeat';
      var startMS = (new Date()).getTime();
      foreground.timer = window.setTimeout("ChangeOpacity('" + foregroundID + "'," + FadeDurationMS + "," + startMS + ",100,0)",10);
    }
  } else {
    foreground.src = newImage;
  }
}
var slideCache = new Array();
function RunSlideShow(pictureID,backgroundID,imageFiles,displaySecs)
{
  var imageSeparator = imageFiles.indexOf(";");
  var nextImage = imageFiles.substring(0,imageSeparator);


  FadeInImage(pictureID,nextImage,backgroundID);
  var futureImages = imageFiles.substring(imageSeparator+1,imageFiles.length)+ ';' + nextImage;
  setTimeout("RunSlideShow('"+pictureID+"','"+backgroundID+"','"+futureImages+"',"+displaySecs+")",displaySecs*1000);
  // Cache the next image to improve performance.
  imageSeparator = futureImages.indexOf(";");
  nextImage = futureImages.substring(0,imageSeparator);
  if (slideCache[nextImage] == null)
  {
    slideCache[nextImage] = new Image;
    slideCache[nextImage].src = nextImage;
  }
}

