function clearChildDivs() {
	for (var i = 0; i < childDivs.length; i++) {
		var divId = childDivs[i].id;
		if (divId != "curtain") { // hides all the divs but the curtain div.
			childDivs[i].className = "fader-logo-invisible";	
		}
	}
}
function determineVisibleDivs () {
	var scrollDivWidth = logoPadding; // start with the logo padding to ensure that the first logo is 10 pixels away from the left edge of the div.
	i = startVisDiv;
	var curLogoDiv;
	while (scrollDivWidth <= divWidth) {
		var divId = "index-logo-" + i;
		curLogoDiv = document.getElementById (divId);
		curLogoDiv.className = "fader-logo-visible";
		curLogoDiv.style.left = scrollDivWidth + "px";
		var curDivWidth = curLogoDiv.scrollWidth;
		scrollDivWidth = eval (scrollDivWidth + curDivWidth + logoPadding * 2);
		i = i + 1; // move on to next div.  Cycle back to first div if i > logosCount.
		if (i > logosCount) {
			i = 0;
		}
	}
	curLogoDiv.className = "fader-logo-invisible";
	startVisDiv = i;
}
function fadeStep (stepValue) {
	opacity = opacity + stepValue;
	if (opacity == maxOpacity) {
		curtainDiv.className = "";
	} else {
		curtainDiv.className = "opacity-" + opacity;
	}
}
function alphaFadeOut() {
	for (var i = 1; i <= maxOpacity; i++) {
		setTimeout ("fadeStep (-1)", faderTimerInterval * i);
	}
}
function alphaFadeIn() {
	for (var i = 1; i <= maxOpacity; i++) {
		setTimeout ("fadeStep (1)", faderTimerInterval * i);
	}
}
function fadeToNewLogos () {
	alphaFadeIn(); // fades in the white div.
	setTimeout ("clearChildDivs()", faderTimerInterval * maxOpacity);
	setTimeout ("determineVisibleDivs()", faderTimerInterval * maxOpacity);
	setTimeout ("alphaFadeOut()", faderTimerInterval * maxOpacity + faderTimerInterval);
}
function createFader () {
	faderDiv = document.getElementById("logos-container");
	childDivs = faderDiv.getElementsByTagName ("div");
	curtainDiv = document.getElementById("curtain");
	faderDiv.style.width = divWidth + "px";
	clearChildDivs();
	determineVisibleDivs();
	var timer = setInterval ("fadeToNewLogos()", timerInterval + faderTimerInterval * maxOpacity * 2);
}
var logoPadding, divWidth, logosCount;
var faderDiv, childDivs, curtainDiv;
var startVisDiv;
var timerInterval = 15000;
var faderTimerInterval = 100; // timeout value between fader levels.
startVisDiv = 0; // first visible div.
var maxOpacity = 10; // opacity level of logos-container div on a scale of 0 to 10.
var opacity = 0;
var faderTimer;