function layerswap(layername){
	if(document.getElementById(layername)){
		if (document.getElementById(layername).style.visibility=='visible'){
			document.getElementById(layername).style.visibility='hidden';
			document.getElementById(layername).style.display='none';
		}else{
			document.getElementById(layername).style.visibility='visible';
			document.getElementById(layername).style.display='block';
		}
	}
}



function layerswapWithControl(layername, hide){
	if(document.getElementById(layername)){
//		if (document.getElementById(layername).style.visibility=='visible'){
//			document.getElementById(layername).style.visibility='hidden';
//			document.getElementById(layername).style.display='none';
//		}else{
//			document.getElementById(layername).style.visibility='visible';
//			document.getElementById(layername).style.display='block';
//		}
		if(hide){
		      document.getElementById(layername).style.visibility='hidden';
		      document.getElementById(layername).style.display='none';
		}
		else{
		    document.getElementById(layername).style.visibility='visible';
                              document.getElementById(layername).style.display='block';
		}
	}
}