var interval = 5.0; // delay between rotating images (in seconds)
var random_display = 1; // 0 = no, 1 = yes
interval *= 1000;
var rotate_phase = 0;

var image_index = 0;

function imageItem(image_location) {
this.image_item = new Image();
this.image_item.src = image_location;
}

function get_ImageItemLocation(imageObj) {
return(imageObj.image_item.src)
}

var last_generated = -999;
var last_generated2 = -999;
var last_generated3 = -999;
var last_generated4 = -999;
var last_generated5 = -999;

function generate(x, y) {
var range = y - x + 1;
var res = Math.floor(Math.random() * range) + x;
while ((res==last_generated) || (res==last_generated2) || (res==last_generated3) || (res==last_generated4) || (res==last_generated5))
      { res = Math.floor(Math.random() * range) + x; }
last_generated5 = last_generated4;
last_generated4 = last_generated3;
last_generated3 = last_generated2;
last_generated2 = last_generated;
last_generated = res;
return res;
}

function getNextImage() {
if (random_display) {
image_index = generate(0, number_of_image-1);
}
else {
image_index = (image_index+1) % number_of_image;
}
var new_image = get_ImageItemLocation(image_list[image_index]);
return(new_image);
}

function rotateImage(place)
{
  rotate_phase++;
  var recur_call = "rotateImage('"+place+"')";
  var imgObj = document.getElementById(place);

  if ((rotate_phase<10) || (rotate_phase>10))
  {
        var op = 0;
    if (rotate_phase<10) op = 100-10*rotate_phase;
    if (rotate_phase>10) op = 10*(rotate_phase-11);
        imgObj.style.opacity=op/100;
        try
        {
          imgObj.style.filter = 'alpha(opacity=' + op + ')';
          // imgObj.style.filters.alpha.opacity=op;
        }
        catch (e) {}
        if (rotate_phase>20)        // konec
        {
        rotate_phase = 0;
            setTimeout(recur_call, interval);
        return;
        }
        setTimeout(recur_call, 30);
        return;

  }
  var new_image = getNextImage();
  imgObj.src = new_image;
  setTimeout(recur_call, 30);
}