var slideshow = {};


slideshow.index = 0;
slideshow.next = null;
slideshow.div = document.getElementById("content");


slideshow.tick = function()
{
    ++slideshow.index;
    slideshow.index %= slideshow.slides.length;
    slideshow.div.style.backgroundImage = "url(img/index/" +
            slideshow.slides[slideshow.index] + ")";
};


slideshow.start = function()
{
    if(slideshow.div)
    {
        slideshow.index =
                Math.floor(Math.random() * slideshow.slides.length);
        slideshow.div.style.backgroundImage = "url(img/index/" +
                encodeURI(slideshow.slides[slideshow.index]) + ")";
        for(var i=0; i<slideshow.slides.length; ++i)
        {
            slideshow.slides[i] = encodeURI(slideshow.slides[i]);
            var img = new Image();
            img.src = "img/index/" + slideshow.slides[i];
        }
        setInterval(slideshow.tick, 5000);
    };
};