//changes the background image and the door images
	//note: can't get the background image to change dynamically in NS4
	//note: at the moment I am not preloading the graffiti images

function DoorGraffiti(doorL_off, doorR_off, doorL_on, doorR_on) {
	this.doorL_off = doorL_off;
	this.doorR_off = doorR_off;
	this.doorL_on = doorL_on;
	this.doorR_on = doorR_on;
}
var Doors = new Array();
	Doors[0] = new DoorGraffiti("","","","");
	Doors[1] = new DoorGraffiti(
		"images/doorL.jpg",
		"images/doorR.jpg",
		"images/door1L_g.jpg",
		"images/door1R_g.jpg");
	Doors[2] = new DoorGraffiti(
		"images/doorL.jpg",
		"images/doorR.jpg",
		"images/door2L_g.jpg",
		"images/door2R_g.jpg");
	Doors[3] = new DoorGraffiti(
		"images/doorL.jpg",
		"images/doorR.jpg",
		"images/door3L_g.jpg",
		"images/door3R_g.jpg");
	Doors[4] = new DoorGraffiti(
		"images/doorL.jpg",
		"images/doorR.jpg",
		"images/door4L_g.jpg",
		"images/door4R_g.jpg");

function graffitiON() {
	if (document.getElementsByTagName) {
		bdy = document.getElementsByTagName("body");
		bdy[0].style.backgroundImage = 'url(images/subway_graffiti.jpg)';
		for (j=1; j<Doors.length; j++) {
			objDoors = Doors[j];
			document["imgDoor"+j+"L"].src = objDoors.doorL_on;
			document["imgDoor"+j+"R"].src = objDoors.doorR_on;
		}
	}
	if (document.layers && !document.getElementById) {//this checks for NS4
		if (document.body){
			document.body.background = "images/subway_graffiti.jpg";
		}
		for (j=1; j<Doors.length; j++) {
			objDoors = Doors[j];
			document["doorway"+j].document["door"+j+"L"].document["imgDoor"+j+"L"].src = objDoors.doorL_on;
			document["doorway"+j].document["door"+j+"R"].document["imgDoor"+j+"R"].src = objDoors.doorR_on;
		}
	}
}
function graffitiOFF() {
	if (document.getElementsByTagName) {
		bdy = document.getElementsByTagName("body");
		bdy[0].style.backgroundImage = 'url(images/subway_tile.jpg)';
		for (j=1; j<Doors.length; j++) {
			objDoors = Doors[j];
			document["imgDoor"+j+"L"].src = objDoors.doorL_off;
			document["imgDoor"+j+"R"].src = objDoors.doorR_off;
		}
	}
	if (document.layers && !document.getElementById) {//this checks for NS4
		if (document.body){
			document.body.background = "images/subway_tile.jpg";
		}
		for (j=1; j<Doors.length; j++) {
			objDoors = Doors[j];
			document["doorway"+j].document["door"+j+"L"].document["imgDoor"+j+"L"].src = objDoors.doorL_off;
			document["doorway"+j].document["door"+j+"R"].document["imgDoor"+j+"R"].src = objDoors.doorR_off;
		}
	}
}