Error when trying to set variable with array

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1

I’m trying to make a tower defense game. I’ve never used array’s before, so i figured now would be a good time. I’m making a enemy, were the goal is to move from waypoint to waypoint. I’m using smoothdamp, so i need target positions, but when i try to set the target positions using the array, i get an error saying “NullReferenceException: Object reference not set to an instance of an object
Boo.Lang.Runtime.RuntimeServices.CheckNumericPromotion (IConvertible convertible)
Boo.Lang.Runtime.RuntimeServices.CheckNumericPromotion (System.Object value)
Boo.Lang.Runtime.RuntimeServices.UnboxSingle (System.Object value)
enemy.Update () (at Assets/scripts/enemy.js:16)”
If anybody can help me figure out why this is happening, i’d very much appreciate it.
Here is my script…

var waypoint : Transform[];
var currentWaypoint : int;

//moving smoothdamp vars
var targetX : float;
var targetZ : float;
var time : float;
private var velocity : float;

function Update()
{
	targetX = waypoint[currentWaypoint].x;
	targetZ = waypoint[currentWaypoint].z;
	
	transform.position.x = Mathf.SmoothDamp(transform.position.x, targetX, velocity, time * Time.deltaTime);
	transform.position.z = Mathf.SmoothDamp(transform.position.z, targetZ, velocity, time * Time.deltaTime);
}

function Awake()
{
	waypoint = Camera.main.GetComponent(waypointsInit).waypoints;
	currentWaypoint = 0;
	targetX = transform.position.x;
	targetZ = transform.position.z;
}

function OnTriggerEnter(hit : Collider)
{
	if(hit.gameObject.tag == "waypoint")
	{
		currentWaypoint += 1;
		print(currentWaypoint);
	}
}

1 Answer

1
2

Your waypoint variable contains an array of Transforms, so it’s waypoint[currentWaypoint].position.x not waypoint[currentWaypoint].x. So

targetX = waypoint[currentWaypoint].position.x;
targetZ = waypoint[currentWaypoint].position.z;

And make sure you have initialized the array in the script that is attached to the camera with some transforms in the inspector, before you run the script.