function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		vf_over = newImage("images/vf-over.gif");
		vf_pitcher_over = newImage("images/vf-pitcher_over.gif");
		pitcher_vf_over = newImage("images/pitcher-vf_over.gif");
		pitcher_over = newImage("images/pitcher-over.gif");
		pitcher_sundew_over = newImage("images/pitcher-sundew_over.gif");
		sundew_over = newImage("images/sundew-over.gif");
		sundew_cobra_over = newImage("images/sundew-cobra_over.gif");
		cobra_sundew_over = newImage("images/cobra-sundew_over.gif");
		cobra_over = newImage("images/cobra-over.gif");
		cobra_nepenthes_over = newImage("images/cobra-nepenthes_over.gif");
		nepenthes_cobra_over = newImage("images/nepenthes-cobra_over.gif");
		nepenthes_over = newImage("images/nepenthes-over.gif");
		nepenthes_butterworts_over = newImage("images/nepenthes-butterworts_over.gif");
		butterworts_nepenthes_over = newImage("images/butterworts-nepenthes_over.gif");
		butterworts_over = newImage("images/butterworts-over.gif");
		preloadFlag = true;
	}
}

//email validation script for email sign up below

function validEmail(email) {
			invalidChars = " /:,;"
	
			if (email == "") {
				return false
			}
			for (i=0; i<invalidChars.length; i++) {
				badChar = invalidChars.charAt(i)
				if (email.indexOf(badChar,0) > -1) {
					return false
				}
			}
			atPos = email.indexOf("@",1)
			if (atPos == -1) {
				return false
			}
			if (email.indexOf("@",atPos+1) > -1) {
				return false
			}
			periodPos = email.indexOf(".",atPos)
			if (periodPos == -1) {
				return false
			}
			if (periodPos+3 > email.length)	{
				return false
			}
			return true
		}

		function submitIt(emailForm) {
			if (!validEmail(emailForm.emailAddr.value)) {
				alert("Invalid email address")
				emailForm.emailAddr.focus()
				emailForm.emailAddr.select()
				return false
			}
	
			return true
		}

//Clam shell menu code. Navigation will not work without this code below.

function toggleClamShellMenu(objectID) {
	if (isAll || isID) {
		domStyle = findDOM(objectID,1);
		if (domStyle.display =='block')  domStyle.display='none';
		else domStyle.display='block';
	}
	else {
		destination = objectID + '.html';
		self.location = destination;
	}
	return;
}