/**
 *	Displays a layer, default css value is 'block', you may
 *	pass your desired displaymode ...
 *	@param string layername
 *	@param string displaymode
 */
function showLayer(layername, displaymode) {
	if (!displaymode) displaymode = "block";
	document.getElementById(layername).style["display"] = displaymode;
}
/**
 *	hides a layer
 */
function hideLayer(layername) {
	showLayer(layername,"none");
}
/**
 *	Toggles Layer from visible to non-visible and the other way around
 *	@param string	layername	
 *	@param string	displaymode
 */	
function toggleLayer(layername, displaymode) {
	if (!displaymode) displaymode = "block";
	current = document.getElementById(layername).style.display;
	current = current.toLowerCase();
	if (current == "block" ||
		current == "" ||
		current == "inline" ||
		current == "list-item" ||
		current == "marker" ||
		current == "table" ||
		current == "inline-table" ||
		current == "table-row" ||
		current == "table-cell") {
		hideLayer(layername);
		return false;
	} else {
		showLayer(layername, displaymode);
		return true;
	}
}

/**
 *	Replaces Image
 */
function replaceImage(layername, img) {
	document.getElementById(layername).src = img;
}

/**
 *	Replace Background Image
 */
function replaceBg(layername, img) {
	document.getElementById(layername).style.background = "url("+img+")";
}

/**
 *	Change Background Color
 */
function changeBg(layername, color) {
	document.getElementById(layername).style.backgroundColor = color;
}

/**
 *	Set Style Property
 */
function layerStyle(layername, propname, value) {
	document.getElementById(layername).style[propname] = value;
}

/**
 *	Set Position of layer
 */
function layerMoveTo(layername, x, y) {
	document.getElementById(layername).style.left = x + "px";
	document.getElementById(layername).style.top = y + "px";
}