Why the enemy is flipping constantly when it collides with an obstacle?

Question

I'm making a 2D platformer with Unity. I have an enemy patrol that shoots bullet. The enemy is working fine until it reaches to a point that should be turn around. (when collides with an obstacle or is near the ledges) The problem is that the enemy flips rapidly in this situation. Also it only shoots to the right despite its facing direction. I'm pretty sure that the problem is from either the bullet or the pistol script because the enemy completely works when the pistol game object is disabled. My goal is to make the enemy flip at those points like before while it shoots the bullets in its facing direction.

Enemy script:

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

public class Enemy : PhysicsObject
{
    [Header("Attributes")]
    private int direction = 1;
    [SerializeField] private float maxSpeed;
    [SerializeField] private LayerMask rayCastLayerMask; //Which layer do we want the raycast to interact with?
    [SerializeField] private Vector2 rayCastOffset; //Offset from the center of the raycast origin
    [SerializeField] private float rayCastLength = 2;
    bool isFacingLeft;

    [Header("References")]
    private RaycastHit2D rightLedgeRaycastHit;
    private RaycastHit2D leftLedgeRaycastHit;
    private RaycastHit2D rightWallRaycastHit;
    private RaycastHit2D leftWallRaycastHit;

    void Update()
    {
        targetVelocity = new Vector2(maxSpeed * direction, 0);

        if (targetVelocity.x < -.01)
        {
            transform.localScale = new Vector2(-1, 1);
            isFacingLeft = true;
        }
        else if (targetVelocity.x > .01)
        {
            transform.localScale = new Vector2(1, 1);
            isFacingLeft = false;
        }

        //Check for right ledge!
        rightLedgeRaycastHit = Physics2D.Raycast(new Vector2(transform.position.x + rayCastOffset.x, transform.position.y + rayCastOffset.y), Vector2.down, rayCastLength);
        Debug.DrawRay(new Vector2(transform.position.x + rayCastOffset.x, transform.position.y + rayCastOffset.y), Vector2.down * rayCastLength, Color.blue);
        if (rightLedgeRaycastHit.collider == null) direction = -1;

        //Check for left ledge!
        leftLedgeRaycastHit = Physics2D.Raycast(new Vector2(transform.position.x - rayCastOffset.x, transform.position.y + rayCastOffset.y), Vector2.down, rayCastLength);
        Debug.DrawRay(new Vector2(transform.position.x - rayCastOffset.x, transform.position.y + rayCastOffset.y), Vector2.down * rayCastLength, Color.green);
        if (leftLedgeRaycastHit.collider == null) direction = 1;

        //Check for right wall!
        rightWallRaycastHit = Physics2D.Raycast(new Vector2(transform.position.x, transform.position.y), Vector2.right, rayCastLength, rayCastLayerMask);
        Debug.DrawRay(new Vector2(transform.position.x, transform.position.y), Vector2.right * rayCastLength, Color.red);
        if (rightWallRaycastHit.collider != null) direction = -1;

        //Check for left wall!
        leftWallRaycastHit = Physics2D.Raycast(new Vector2(transform.position.x, transform.position.y), Vector2.left, rayCastLength, rayCastLayerMask);
        Debug.DrawRay(new Vector2(transform.position.x, transform.position.y), Vector2.left * rayCastLength, Color.magenta);
        if (leftWallRaycastHit.collider != null) direction = 1;
    }
}

Pistol script:

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

public class Pistol : MonoBehaviour
{
    [SerializeField] GameObject bullet;
    [SerializeField] Transform bulletSpawnPos;
    private bool IsShooting;

   [SerializeField] private float shootDelay = .5f;
    private bool isFacingLeft;

    void Start()
    {
        InvokeRepeating("Shoot",4f, shootDelay);
        Rigidbody2D rb = GetComponent<Rigidbody2D>();
      
    }

    void Update()
    {
       if (IsShooting) return;
        IsShooting = true;
        GameObject b = Instantiate(bullet);
        b.GetComponent<Bullet>().StartShoot(isFacingLeft);
        b.transform.position = bulletSpawnPos.transform.position;
       

        Invoke("ResetShoot", shootDelay);
    }

   void ResetShoot()
   {
      IsShooting = false;    
    }
}

Bullet script:

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

public class Bullet : MonoBehaviour
{
    [SerializeField] float speed;
    [SerializeField] int damage;
    float timeToDestroy = 3;

    public void StartShoot(bool isFacingLeft)
    {
        Rigidbody2D rb = GetComponent<Rigidbody2D>();

        if (isFacingLeft)
        {
            rb.velocity = new Vector2(-speed, 0);
        }
        else
        {
            rb.velocity = new Vector2(speed, 0);
        }

        Destroy(gameObject, timeToDestroy);
    }
}

Answer 1

Your pistol and your enemy each have their own isFacingLeft bool currently. Pistol gets never updated with the value and just uses the default one. So you need to be able to get the isFacingLeft from your Enemy script in the Pistol script. You could either

• Have a getter for it
• Make it public

A getter is better since the logic on when it is true or false is handled in Enemy already and we do not want other scripts be able to change the value.

Add this code to your Enemy script

public bool IsFacingLeft() {
    return isFacingLeft;
}

Updated pistol script

private Enemy _enemy;
void Start()
{
    //Getting once a reference to the enemy that is holding the pistol, you 
    //could as well assign this in the editor if you make it public
    _enemy = GetComponent<Enemy>();
    InvokeRepeating("Shoot", 4f, shootDelay);
}

void Shoot() {
    GameObject b = Instantiate(bullet);
    b.GetComponent<Bullet>().StartShoot(_enemy.IsFacingLeft());
    b.transform.position = bulletSpawnPos.transform.position;
}

The old Update code in Pistol is not needed anymore. There are no changes to the Bullet script.