function checkEmail(e)
{
	var re = new RegExp("^[A-Za-z0-9_-]+[A-Za-z0-9_\.\-]*[A-Za-z0-9_-]+@[A-Za-z0-9_-]+[A-Za-z0-9\.-]*\\.[a-zA-Z]{2,6}$","i");
	
	return re.test(e);
}

function checkLogin()
{
	if(!checkEmail(document.login_form.login_email.value))
	{
		alert('Your email address is invalid!');
		return false;
	}
}

function checkRegister()
{
	if(!checkEmail(document.login_form.register_email.value))
	{
		alert('Your email address is invalid!');
		return false;
		
	}
}


var overlay_pointer = 0;

function loadSectionOverView(id)
{
	
	hideSectionOverview();
	
	document.getElementById('section'+id).style.display = "block";
	overlay_pointer = document.getElementById('section'+id);
}

function hideSectionOverview()
{
	if(overlay_pointer != 0)
	{
		overlay_pointer.style.display = "none";
	}
}


//change the opacity for different browsers
function changeOpac(id,opacity)
{
	var object = document.getElementById(id).style;
	object.opacity = (opacity / 100);
	object.MozOpacity = (opacity / 100);
	object.KhtmlOpacity = (opacity / 100);
	object.filter = "alpha(opacity=" + opacity + ")";
	return true;
}


function imageRollOpacity(imgObjRef)
{
	
	changeOpac(imgObjRef.id,70);
}

function imageOutOpacity(imgObjRef)
{
	changeOpac(imgObjRef.id,100);
}