// JavaScript Document
var images = 18;
var show   = 5;
var preLoad = new Array();


function preload_images(){
  	for (i = 0; i <= images-1; i++){
	   image_no = i+1;
       preLoad[i] = new Image()
       preLoad[i].src = 'graphics/rotation/' + image_no + '.jpg';
    }
}

function zufallszahl(n) {
     zahl = Math.floor(Math.random() * (n));
     return zahl;
 }


function FadeIn(i){
    var image = "slide"+i;
	if( preLoad.length <= 1 ){ preload_images(); }

	var rand = zufallszahl(preLoad.length);
	$('slide'+i).src = preLoad[rand].src;
	preLoad.splice(rand,1);

	Effect.Appear(image,{queue:{scope:'myscope', position:'end'}});
}

function FadeOut(i){
	var image = "slide"+i;
    var imagebg = "slidebg"+i;

	if( preLoad.length <= 1 ){ preload_images(); }

	var rand = zufallszahl(preLoad.length);
	$('slidebg'+i).setAttribute('style','background-image: url('+preLoad[rand].src+');');// = ;
	preLoad.splice(rand,1);

	Effect.Fade(image,{queue:{scope:'myscope', position:'end'}});
}

function ImageRotation(i){
 		var image = "slide"+i;
		if( Element.visible( image ) == true ){
		    setTimeout( 'FadeOut('+i+')', 1000);
		}
		else{
			setTimeout( 'FadeIn('+i+')', 1000);
		}

		if( i >= 5 ){
	   		i=1;
	    }
		else{
	   		i++;
		}

	setTimeout( 'ImageRotation('+i+')', 2000);
}