var TimeToFade = 1000.0;
var imgInCorso = 1;
var verso = 'avanti'
function fade(eid) {
    var element = document.getElementById(eid);
    if (element == null)
        return;

    if (element.FadeState == null) {
        if (element.style.opacity == null
        || element.style.opacity == ''
        || element.style.opacity == '1') {
            element.FadeState = 2;
        }
        else {
            element.FadeState = -2;
        }
    }

    if (element.FadeState == 1 || element.FadeState == -1) {
        element.FadeState = element.FadeState == 1 ? -1 : 1;
        element.FadeTimeLeft = TimeToFade - element.FadeTimeLeft;
    }
    else {
        element.FadeState = element.FadeState == 2 ? -1 : 1;
        element.FadeTimeLeft = TimeToFade;
        setTimeout("animateFade(" + new Date().getTime() + ",'" + eid + "')", 33);
    }
}
function animateFade(lastTick, eid) {
    var curTick = new Date().getTime();
    var elapsedTicks = curTick - lastTick;
    var element = document.getElementById(eid);
    if (element.FadeTimeLeft <= elapsedTicks) {
        element.style.opacity = element.FadeState == 1 ? '1' : '0';
        element.style.filter = 'alpha(opacity = ' + (element.FadeState == 1 ? '100' : '0') + ')';
        element.FadeState = element.FadeState == 1 ? 2 : -2;
        if (verso == 'avanti') {
            imgInCorso = imgInCorso + 1;
        } else {
            imgInCorso = imgInCorso - 1;
        }

        return;
    }

    element.FadeTimeLeft -= elapsedTicks;
    var newOpVal = element.FadeTimeLeft / TimeToFade;
    if (element.FadeState == 1) newOpVal = 1 - newOpVal;
    element.style.opacity = newOpVal;
    element.style.filter = 'alpha(opacity = ' + (newOpVal * 100) + ')';
    setTimeout("animateFade(" + curTick + ",'" + eid + "')", 33);
}


function loopFade(numImg) {
    //alert(arrayId.length);
    if (imgInCorso > numImg) {
        imgInCorso = numImg;
        verso = "indietro"
    }

    if (imgInCorso < 1) {
        imgInCorso = 1;
        verso = "avanti"
    }
    fade('pic' + imgInCorso);
}

var continua = 0;
var continua_tmp = 0;

function looppaFade() {

    if (continua === continua_tmp) {
        setTimeout(looppaFade, 50);
        return;
    }
    continua_tmp = continua;

}