Unity - 将平台从 A 点移动到 B 点

Question

I am trying to make a game in Unity and I am stuck in a part where I am trying to move a platform from Point A to Point B.

The error I get is:

NullReferenceException: Object reference not set to an instance of an object MovingPlatform.Update () (at Assets/Scripts/MovingPlatform.cs:30)

The Source Code is:

public class MovingPlatform: MonoBehaviour

{

[SerializeField]
private Transform pointA, pointB;

private float speed = 1.0f;

private Transform target;

// Start is called before the first frame update
void Start()
{
    
}

// Update is called once per frame
void Update()
{
    if (transform.position == pointA.position)
    {
        target = pointB;
    }
    else if (transform.position == pointB.position)
    {
        target = pointA;
    }
    
    transform.position = Vector3.MoveTowards(transform.position, target.position, speed * Time.deltaTime);

}

}

What should I do?

Because the platform is not moving at all.

Answer 1

The error tells you whats wrong. In line 30 of your script you have a reference somewhere which is null (hence NullReferenceException ) and you try to do something with this (eg accessing attributes). I guess its target.position from

transform.position = Vector3.MoveTowards(transform.position, target.position, speed * Time.deltaTime);

when your if -statements dont trigger. You should add target = pointB; in Start() to have target properly initialized (i assume you want start out moving to pointB ).