Question How to create a condition for my coroutine

How do i create a condition so that it only spawns 3 enemy at a time and will only only spawn new enemy if there is less than 3 enemy. below is my code, please help

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

public class EnemySpawner : MonoBehaviour
{
[SerializeField] private GameObject logPrefab;

[SerializeField] private float logInterval = 10f;

// Start is called before the first frame update
void Start()
{
StartCoroutine(spawnEnemy(logInterval, logPrefab));
}

// Update is called once per frame
void Update()
{

}

private IEnumerator spawnEnemy(float interval, GameObject enemy)
{
yield return new WaitForSeconds(interval);
GameObject newEnemy = Instantiate(enemy, new Vector3(Random.Range(2f, 6f), Random.Range(7f, 11f), 0), Quaternion.identity);
StartCoroutine(spawnEnemy(interval, enemy));
}
}

 

Hi, it's your first post, but please look around and try using code tags, because it makes the code formatted and much easier to read.

Code (csharp):

1. using System.Collections.Generic;
2. using UnityEngine;
3.  
4. public class EnemySpawner : MonoBehaviour {
5.  
6.   [SerializeField] GameObject _prefab;
7.   [SerializeField] float _timeInterval = 10f;
8.   [SerializeField] [Min(1)] int _enemiesToSpawn = 3;
9.  
10.   int _enemyCount;
11.   List<GameObject> _enemies;
12.  
13.   void Start() {
14.     _enemyCount = 0;
15.     _enemies = new List<GameObject>();
16.     StartCoroutine(spawnEnemies);
17.   }
18.  
19.   void Update() {
20.     if(_enemyCount == _enemiesToSpawn) {
21.       StopCoroutine(spawnEnemies);
22.       printList(_enemies);
23.       enabled = false;
24.     }
25.   }
26.  
27.   IEnumerator spawnEnemies() {
28.     while(_enemyCount < _enemiesToSpawn)
29.       yield return new WaitForSeconds(_timeInterval);
30.       if(trySpawnNewEnemy(_prefab)) _enemyCount++;
31.     }
32.   }
33.  
34.   bool trySpawnNewEnemy(GameObject prefab) {
35.     var newEnemy = Instantiate(prefab, new Vector3(Random.Range(2f, 6f), Random.Range(7f, 11f), 0), Quaternion.identity);
36.     _enemies.Add(newEnemy);
37.     return true; // true for success, could fail for some reason not covered here
38.   }
39.  
40.   void printList<T>(IList<T> list) where T : UnityEngine.Object {
41.     for(int i = 0; i < list.Count; i++) {
42.       Debug.Log(list[i].name);
43.     }
44.   }
45.  
46. }

Something like that.
Some of this code is just decorational / illustrational (namely Update and printList).

edit:
added StopCoroutine

 

May I suggest not using coroutine for this case? It's a bit overkill for the situation.
When an enemy is dead, I bet you have a function that does something. So in that function add an IF statement that checks the number of enemies. If you need to spawn a new one, just spawn a new one instantly.
That way, you don't need to check inside the Update if the number has changed.

 

Yes you may. I just did what OP asked for.