var forum = new Image();
forum.src = 'images/menu_forum.jpg';

var forumOn = new Image();
forumOn.src = 'images/menu_forum_over.jpg';

var equip = new Image();
equip.src = 'images/menu_equip.jpg';

var equipOn = new Image();
equipOn.src = 'images/menu_equip_over.jpg';

var trip = new Image();
trip.src = 'images/menu_trip.jpg';

var tripOn = new Image();
tripOn.src = 'images/menu_trip_over.jpg';

var contact = new Image();
contact.src = 'images/menu_contact.jpg';

var contactOn = new Image();
contactOn.src = 'images/menu_contact_over.jpg';

var study = new Image();
study.src = 'images/menu_study.jpg';

var studyOn = new Image();
studyOn.src = 'images/menu_study_over.jpg';

// menu functions
function doOver(obj, pic){
	var picture = eval(pic + "On");
	obj.src = picture.src;
}

function doOut(obj, pic){
	var picture = eval(pic + "");
	obj.src = picture.src;
}

//
var current_id = 0;
var time;
function openMenu(id){
	doClose(current_id);
	current_id=id;
	overSub();
	var menu = document.getElementById("submenu"+id);
	menu.style.visibility = 'hidden';
		
	var center = Math.round(document.body.clientWidth/2);
	var x,y;
	
	switch(id){
		case 1:
			y = 78;
			x = center-347;
			break;
		case 2:
			y = 79;
			x = center+232;
			break;
		case 3:
			y = 203;
			x = center-48;
			break;
		case 4:
			y = 147;
			x = center+155;
			break;
		case 5:
			y = 147;
			x = center-267;
			break;
	}
	//alert(center - event.x);
	menu.style.top = y;
	menu.style.left = x;
	
	menu.style.visibility = 'visible';
}
function closeMenu(id){
	time = setTimeout("doClose(" + id + ")", 50);
	//doClose(id);
}
function doClose(id){
	var menu = document.getElementById("submenu"+id);
	if(menu)
		menu.style.visibility = 'hidden';
}
function overSub(){
	clearTimeout(time);
}