var tmrFeedback;
var tFeedback;
var objFeedback;

function overlay_feedback() {
	objFeedback = gObjFeedback();
	sLftFeedback();
	shwFeedback(true);
	tFeedback = 0;
	sTmrFeedback();
}

function hFaFeedback() {
	tFeedback = -100;
	sTmrFeedback();
	return false;
}

function sTmrFeedback() {
	tmrFeedback = setInterval("fdFeedback()",20);
}

function fdFeedback() {
	var amtFeedback = Math.abs(tFeedback+=10);
	if(amtFeedback == 0 || amtFeedback == 100) clearInterval(tmrFeedback);
	amtFeedback = (amtFeedback == 100)?99.999:amtFeedback;
  	
	objFeedback.style.filter = "alpha(opacity:"+amtFeedback+")";
	objFeedback.style.KHTMLOpacity = amtFeedback/100;
	objFeedback.style.MozOpacity = amtFeedback/100;
	objFeedback.style.opacity = amtFeedback/100;
	
	if(amtFeedback == 0) shwFeedback(false);
}

function sLftFeedback() {
	var wFeedback = 20;	// set this to 1/2 the width of the fa div defined in the style sheet 
			// there's not a reliable way to retrieve an element's width via javascript!!
					
	var lFeedback = (document.body.innerWidth)? document.body.innerWidth / 2:document.body.offsetWidth / 2;

	objFeedback.style.left = (lFeedback - wFeedback)+"px";
}

function gObjFeedback() {
	return document.getElementById("overlay_feedback");	
}

function shwFeedback(b) {
	(b)? objFeedback.className = 'show':objFeedback.className = '';	
}