function filter(image, source) {
	image.src= "images/"+source;
}

function login_kun(world_id) {
	document.getElementById('world_id').value = world_id;
	document.login_form.submit();
}

function choose_world() {
	iBox.showURL('#maailm', '', {height: 143, width: 300});
}

function check_submit() {
	if (document.getElementById('world_id').value == false) {
		choose_world();
		return false;
	}
	return true;
}