(document.layers)? layerobject=true : layerobject=false;
(document.all)? allobject=true : allobject=false;
(document.getElementById)? dom=true : dom=false;

function getElement(layerName, parentLayer)
{
if(layerobject)
	{
	parentLayer=(parentLayer) ? parentLayer : self;
	layerCollection=parentLayer.document.layers;
	if(layerCollection[layerName])
		{return layerCollection[layerName];}
	for (i=0;i<layerCollection.length;) return(getElement(layerName,layerCollection[i++]));
	}
if (allobject) {return document.all[layerName];}
if (dom) {return document.getElementById(layerName);}
}

function toggleLayer(lname)
{
var mcapa=getElement(lname);
var vis=false;
if (layerobject)
	{vis=((mcapa.visibility=='show')? true: false);}
else
	{vis=((mcapa.style.visibility=='visible')? true: false);}
	
if (layerobject)
	{mcapa.visibility=(vis ? 'hide' : 'show');}
else
	{mcapa.style.visibility=(vis ? 'hidden' :'visible');}
}

function LayerOn(lname)
{
	var mcapa=getElement(lname);
	if (layerobject)
		{mcapa.visibility='show';}
	else
		{mcapa.style.visibility='visible';}
}

function LayerOff(lname)
{
	var mcapa=getElement(lname);
	if (layerobject)
		{mcapa.visibility='hide';}
	else
		{mcapa.style.visibility='hidden';}
}