/* Drop Down Menus */
	
	sfhover=function() {
		var sfels=document.getElementById("navigation").getElementsByTagName("li");
			for (var i=0; i<sfels.length; i++) {
				sfels[i].onmouseover=function() {
				this.className+=" sfhover";
				}
			sfels[i].onmouseout=function() {
				this.className=this.className.replace(" sfhover", "");
			}
		}
	}

	if (window.attachEvent) window.attachEvent ("onload", sfhover);
	

/* 	Graphics Page: Preload 4 images (1 small and 3 large) */	

	var picsgraphics = new Array("_images/graphEyeSmall.jpg", "_images/graphEye.jpg", 
	"_images/graphHTBridge.jpg", "_images/graphHWestminster.jpg");	
	
	var preloadgraphics = new Array();
	
		preloadgraphics[0] = new Image(100,75);
		preloadgraphics[0].src = picsgraphics[0];
	
		for(var i=1; i<picsgraphics.length; i++) {
			preloadgraphics[i] = new Image(360,270);
			preloadgraphics[i].src = picsgraphics[i];
		}
	

/* 	Graphics Page: Swap same size images */	
	
	function swapsamesize(n) {
		if(n==0) document.images.samesize.src= preloadgraphics[2].src;
		if(n==1) document.images.samesize.src= preloadgraphics[3].src;	
	}	


/* 	Graphics Page: Small popup in centre of screen */

	leftPos=0
	if (screen) {
		leftPos=screen.width/2-200;
		topPos=screen.height/2-150;
	}
	
	function newWindow1() {
		pw = window.open("_images/graphEye.jpg", "Eye", 
		"width=400,height=300,top="+topPos+",left="+leftPos+",scrollbars=0");	
	}


/* 	Graphics Page: Larger popup, with text, in top left corner	*/
	
	function newWindow2() {
		pw = window.open("Popup.htm", "Eye",
		"width=600,height=500,top=0,left=0,scrollbars=0");
	}
	

/* 	Graphics Page: Mouseover Gallery */	
	
	
	imageSwapPic1=new Image();
	imageSwapPic1.src="_images/graphIGFMedium.jpg";
	imageSwapPic2=new Image();
	imageSwapPic2.src="_images/graphBAMedium.jpg";
	imageSwapPic3=new Image();
	imageSwapPic3.src="_images/graphBlossomMedium.jpg";
	imageSwapPic4=new Image();
	imageSwapPic4.src="_images/graphMPMedium.jpg";
	
	
	function swapPic(n) {
		if(document.layers){
 		//thisbrowser="NN4";
 				if (n==0) document.images.bigHpic.src=imageSwapPic1.src;
				if (n==1) document.images.bigHpic.src=imageSwapPic2.src;
				if (n==2) document.images.bigHpic.src=imageSwapPic3.src;
				if (n==3) document.images.bigHpic.src=imageSwapPic4.src;		
		}
		else
		if(document.all){
		//thisbrowser="ie";
				if (n==0) document.images.bigHpic.src=imageSwapPic1.src;
				if (n==1) document.images.bigHpic.src=imageSwapPic2.src;
				if (n==2) document.images.bigHpic.src=imageSwapPic3.src;
				if (n==3) document.images.bigHpic.src=imageSwapPic4.src;	
		}
		else
		if(!document.all && document.getElementById){
		//thisbrowser="NN6";
				if (n==0) document.images.bigHpic.src=imageSwapPic1.src;
				if (n==1) document.images.bigHpic.src=imageSwapPic2.src;
				if (n==2) document.images.bigHpic.src=imageSwapPic3.src;
				if (n==3) document.images.bigHpic.src=imageSwapPic4.src;
		}
	}


/* 	Graphics Page: Show hidden layer */
	
	function showbig(n) {
		var smalllayer;
		var largelayer;

		if(document.layers){
 		//thisbrowser="NN4";
			if (n==1) document.largelayer.visibility="show";
			if (n==0) document.largelayer.visibility="hide";
		}
		if(document.all){
		//thisbrowser="ie"
			if (n==1) document.all.largelayer.style.visibility="visible"; 
			if (n==0) document.all.largelayer.style.visibility="hidden";
		}
		if(!document.all && document.getElementById){
		//thisbrowser="NN6";
			if (n==1) document.getElementById("largelayer").style.visibility="visible";
			if (n==0) document.getElementById("largelayer").style.visibility="hidden";
		}
	}