var speed = 3;
var slideshow_boxes = 3;
var slided = false;
var stay_on_page = true;

function setOpacity (opacity, object) {
 document.getElementById(object).style.opacity=opacity/100;
 document.getElementById(object).style.filter='alpha(opacity='+opacity+')';
}

function showElement (object) {
 if (!(document.getElementById (object) == null)) {
  document.getElementById(object).style.opacity=0;
  document.getElementById(object).style.filter='alpha(opacity=0)';
  document.getElementById(object).style.display='block';
  var opacity = 0;
  var delay = 1;
  do {
   setTimeout('setOpacity('+opacity+',"'+object+'")',delay*speed);
   opacity=opacity+speed;
   delay=delay+speed;
  } while (opacity <= 100);
 }
}

function hideElement (object, show, objectToShow) {
 if (!(document.getElementById (object) == null)) {
  var opacity = 100;
  var delay = 1;
  do {
   setTimeout('setOpacity('+opacity+',"'+object+'")',delay*speed);
   opacity=opacity-speed;
   delay=delay+speed;
  } while (opacity >= 0);
  setTimeout('document.getElementById("'+object+'").style.display="none";',delay*speed);
  if (show && !(document.getElementById (objectToShow) == null)) {
   setTimeout('showElement("'+objectToShow+'")',delay*speed);
  }
 }
}

function slide (start) {
 if (!slided || !stay_on_page) {
  if (start) { 
   now = 1;
  } else {
   var next = now + 1;
   if (slideshow_boxes == now) { next = 1; }
   hideElement ('slideshow-'+now, 1, 'slideshow-'+next);
   now = next;
  }
  setTimeout ('slide ()', 13000);
 }
}

function slide_to (to, from) {
 slided = true;
 hideElement ('slideshow-'+from, 1, 'slideshow-'+to);
}