function setOpacity(opacity_value, figure) {
 	document.getElementById(figure).style.opacity = opacity_value / 10;
 	document.getElementById(figure).style.filter = 'alpha(opacity=' + opacity_value * 50 + ')';
}

function fadePopup(figure) {
 	var opacity_value = 0;
	for( var i = 0 ; i <= 100 ; i++ ) {
		setTimeout( 'setOpacity(' + (i / 10) + ',"'+figure+'")' , 2 * i );}	
}

function swapPopup(figure_show, figure_hide) {	
 	document.getElementById(figure_hide).style.display = "none"; /* hides div figure */	
 	document.getElementById(figure_show).style.display = "block";
	document.getElementById(figure_show).style.opacity = 0;
	document.getElementById(figure_show).style.filter = "alpha(opacity = 0)";
	fadePopup(figure_show);
}

function highlightTxt(text_id) {	
	document.getElementById(text_id).style.background = '#f9f4c7';
}


function slideRevealTxt(index) {	
	var sup_content = "sup_content" + index;
	var expand_link = "expand_link" + index;
	var collapse_link_top = "collapse_link_top" + index;
	var collapse_link_bottom = "collapse_link_bottom" + index;
	document.getElementById(expand_link).style.display = "none";
	document.getElementById(collapse_link_top).style.display = "inline";
	document.getElementById(collapse_link_bottom).style.display = "inline";
 	document.getElementById(sup_content).style.display = "block";
	document.getElementById(sup_content).style.opacity = 0;
	document.getElementById(sup_content).style.filter = "alpha(opacity = 0)";
	fadePopup(sup_content);
}

function slideHideTxt(index) {	
	var sup_content = "sup_content" + index;
	var expand_link = "expand_link" + index;
	var collapse_link = "collapse_link_top" + index;
 	document.getElementById(sup_content).style.display = "none";
	document.getElementById(expand_link).style.display = "inline";
	document.getElementById(collapse_link).style.display = "none";
}

function toggleText(img, text_block) {
	if (document.getElementById(text_block).style.display == "inline") 
		{
		document.getElementById(img).src = "/img/icon_rightarrow.gif";
		document.getElementById(text_block).style.display = "none";
		} else {
			document.getElementById(img).src = "/img/icon_downarrow.gif";
			document.getElementById(text_block).style.display = "inline";
			}
}