Bullet not getting Instantiated when destroyed - Unity2D

Question

I am new to using unity and I am still learning C#. So pls bear with me if the problem mentioned below may seem a little odd or easy to fix.

I am creating a project in order to try to shoot a bullet from a turret, and I have included a function in my bullet script that will destroy the bullet after it has crossed certain boundaries and a function in my bulletSpawner script to Instantiate the bullet if it is destroyed. For some reason whenever I play and shoot the bullet and it crosses the boundary, it doesn't get cloned

Here is the Bullet script;

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Bullet : MonoBehaviour
{
    [SerializeField]
    private float Power = 50f;

    private Rigidbody2D myBody;

    private SpriteRenderer sr;

    private float posX;

    private float posY;

    private void Awake()
    {
        myBody = GetComponent<Rigidbody2D>();
        sr = GetComponent<SpriteRenderer>();
    }

    void Update()
    {
        Shoot();
        destroyBullet();
    }

    void Shoot()
    {
        if (Input.GetKeyDown(KeyCode.Space))
        {
           myBody.AddForce(new Vector2(Power, Power - myBody.gravityScale), 
           ForceMode2D.Impulse);
        }
    }

    void destroyBullet()
    {
        posX = transform.position.x;
        posY = transform.position.y;
        if (posX > 100 || posX < -100 || posY > 100 || posY < -100)
            Destroy(gameObject);
    }
}//class

Here is the BulletSpawner script

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class BulletSpawner : MonoBehaviour
{
    public Transform bullet; 

    void Update()
    {
        StartCoroutine(SpawnBullet());
    }

    IEnumerator SpawnBullet()
    {
        while (!GameObject.FindWithTag("Bullet"))
        {
            yield return new WaitForSeconds(3);

            Instantiate(bullet);

        }//while
    }//Ienum        
}//class

Note: I have attached my Bullet Prefab to bullet in the inspector panel

Whenever the bullet is out of bounds, or gets destroyed, I get this error:

MissingReferenceException: The object of type 'Transform' has been destroyed but you are still trying to access it.

I know it has been destroyed but I want to find a way to access it so that it can clone the bullet(which can be fired again, destroyed and so on...)

Please advise on what I can do to fix this code, or any alternatives in order to prevent such errors from happening in the future. Any feedback would be appreciated :) ...

Thanks in advance!

Answer 1

This answer is just a slight correction to the code that derHugo has written above,

Here is the edited version, the changes are marked in ** below...

public class BulletSpawner : MonoBehaviour
{
   
    public Rigidbody2D bullet;
    public Transform bulletPos;//change**

    [SerializeField]
    private float Power = 50f;

    void Start()
    {
        StartCoroutine(SpawnBullets());
    }

    void Update() { 

    }
    
    IEnumerator SpawnBullets()
    {
        
        bullet.simulated = false;
       
        while (true)
        {
            
            yield return new WaitUntil(() => Input.GetKeyDown(KeyCode.Space));
           
            bullet.simulated = true;
            
            bullet.AddForce(new Vector2(Power, Power - bullet.gravityScale), 
            ForceMode2D.Impulse);

            
            yield return new WaitUntil(() => bullet.position.magnitude > 100f  
            || hasHitSomething */);

    
            bullet.velocity = Vector2.zero;
            bullet.angularVelocity = 0;
          
            bulletPos.position = Vector2.zero;//change**
            bullet.rotation = 0;
           
            bullet.simulated = false;

         
            bullet.gameObject.SetActive(false);

     
            yield return new WaitForSeconds(3);

         
            bullet.gameObject.SetActive(true);
        }
    }
}    

I have done the two changes because when the bullet gets fired and goes out of bounds, the bullet's position does not go back to it's original position (that is (0,0)) that may be because in the code, bullet is declared as the rigidbody for my Bullet object (this meant that the rigidbody will revert it's position back to the origin, not the Bullet object itelf...which doesn't make sense!) .So I had to declare bulletPos as the Transform component of the Bullet object and change bullet to bulletPos in

bullet.position = Vector2.zero;

This is to ensure that the Bullet object instead of the bullet rigidbody reverts it's position back to the origin.

Don't forget to attach the transform component of the bullet to the script in bulletSpawner, then it will run smoothly...

Just wanted to include this so that the same mistake is not made again.