function pic_on(str)
 {
  document.images[str].src = "img/menu/" + str + "_a.gif";
 }
 
function pic_off(str)
 {
  document.images[str].src = "img/menu/" + str + ".gif";
 }
 
function pic_on_jpg(str)
 {
  document.images[str].src = "img/" + str + "_a.jpg";
 }
 
function pic_off_jpg(str)
 {
  document.images[str].src = "img/" + str + ".jpg";
 }

function openWin(site,name,width,height,controls) {

	intLeft=Math.round((screen.width-width)/2);
	intTop=Math.round((screen.height-height)/4);
	
	if(screen.width<=800 || screen.height<=600 || controls=='no') {
		features="no";
	}
	else {
		features="yes";
	}


	var wind=window.open(site,name,'left='+intLeft+',top='+intTop+',offsetX='+intLeft+',offsetY='+intTop+',scrollbars='+controls+',statusbar=no,toolbar=no,width='+width+',height='+height+',location=no,menubar=np');
	wind.focus();
	return;
}

function openGallery()
 {
	openWin('gallery.php','gallery_win',790,580,'no');
 }
 
function openWerkstatt()
 {
	openWin('werkstatt.php','werkstatt_win',790,580,'yes');
 }