var arrMapImg = [];
var arrNavImg = [];
var preloadFlag = false;


function addMapImg(id, srcNam)
{
	arrMapImg[id] = {imagesrc: new Image()};
	arrMapImg[id].imagesrc.src = srcNam;
}

function addNavImg(id, src_on, src_off)
{
	arrNavImg[id] = {on: new Image(), off: new Image()};
	arrNavImg[id].on.src = src_on;
	arrNavImg[id].off.src = src_off;
}

function changeNavImg(id, isOn, swapVal)
{
	document.getElementById(id).src = isOn ? arrNavImg[swapVal].on.src : arrNavImg[swapVal].off.src;
}

function changeMapImg(id, swapVal)
{
	document.getElementById(id).src = arrMapImg[swapVal].imagesrc.src;
}



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

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



function preloadImagesGeneral() {
	if (document.images) {
		addNavImg('0', 'images/nav_synopsis_on.gif', 'images/nav_synopsis_off.gif');
		addNavImg('1', 'images/nav_screenings_on.gif', 'images/nav_screenings_off.gif');
		addNavImg('2', 'images/nav_awards_on.gif', 'images/nav_awards_off.gif');
		addNavImg('3', 'images/nav_filmmakers_on.gif', 'images/nav_filmmakers_off.gif');
		addNavImg('4', 'images/nav_advisors_on.gif', 'images/nav_advisors_off.gif');
		addNavImg('5', 'images/nav_profile_on.gif', 'images/nav_profile_off.gif');
		addNavImg('6', 'images/nav_contact_on.gif', 'images/nav_contact_off.gif');

		preloadFlag = true;
	}
}


function preloadImagesScreenings() {
	if (document.images) {
		addNavImg('0', 'images/nav_synopsis_on.gif', 'images/nav_synopsis_off.gif');
		addNavImg('1', 'images/nav_screenings_on.gif', 'images/nav_screenings_off.gif');
		addNavImg('2', 'images/nav_awards_on.gif', 'images/nav_awards_off.gif');
		addNavImg('3', 'images/nav_filmmakers_on.gif', 'images/nav_filmmakers_off.gif');
		addNavImg('4', 'images/nav_advisors_on.gif', 'images/nav_advisors_off.gif');
		addNavImg('5', 'images/nav_profile_on.gif', 'images/nav_profile_off.gif');
		addNavImg('6', 'images/nav_contact_on.gif', 'images/nav_contact_off.gif');

		addMapImg('0', 'images/screenings_map_natl.gif');
		addMapImg('1', 'images/screenings_map_west.gif');
		addMapImg('2', 'images/screenings_map_midwest.gif');
		addMapImg('3', 'images/screenings_map_southeast.gif');
		addMapImg('4', 'images/screenings_map_northeast.gif');

		preloadFlag = true;
	}
}