How do I spawn an enemy at one of many spawn points in Unity?

Question

I have a spawn script that so far only creates one Enemy spawn point and enemy trigger while only spawning one enemy.

Instead, I want it to create multiple spawns and triggers, but keep it such that only one enemy spawns at a time, at a random on of the spawn points.

How can I do this?

---

Here's the relevant code at the moment:

public class SpawnManager : MonoBehaviour {

    public GameObject Enemy; // the enemy prefab
    public float mytimer; // the time to wait before spawn

    private GameObject _spawndEnemy; // the enemy that was spawnd

    void SpawnEnemy()
    {
        var enemySpawnPoint =  GameObject.Find("FFEnemySpawn1").transform;
        _spawndEnemy = Instantiate(Enemy, enemySpawnPoint.position, enemySpawnPoint.rotation) as GameObject;
    }

    void OnTriggerEnter(Collider other)
    {
        if (other.gameObject.name == "FFMirror1") {
            mytimer = Random.Range(0,15);
            Destroy(_spawndEnemy);
            Invoke("SpawnEnemy", mytimer);
            Debug.Log("Spawn Normal");
        }

    }
}

Answer 1

This falls under the Single Responsibility Principle (see SOLID).

Specifically:

• the spawn point should handle entity creation, rather than a manager
• you would want to either have a field on the spawn point or a parameter on the spawn method that would tell it what to spawn
• you would then use an ordinary trigger behavior (maybe called TriggerSpawn, with a target array field) to trigger the spawn point
• tag the spawned entity so that you can locate it later, rather than referencing it within the entity that created it
• once the entity is spawned, you can disable the trigger until some condition is met (the entity could enable the trigger if it's destroyed), or you could disable the spawn points, etc.

Answer 2

I got this random spawning code I made if it helps. I'm sure its not hard to have it spawning one person at a time.

    public class SpawnScript : MonoBehaviour
{
    public GameObject player;

    void Start()
    {
        GameObject theSpawn;

        do  // checks an error
        {
            getSpawn(gameObject); // grabs random spawn
            theSpawn = getSpawn(gameObject);
        } while (theSpawn == gameObject);

        player.transform.position = theSpawn.transform.position; // changes players position
    }

    private GameObject getSpawn(GameObject spawn)
    {
        Transform[] childs; // spawn list childs transform
        GameObject randomSpawn; // random spawn game object

        childs = (Transform[])spawn.GetComponentsInChildren<Transform>(); // gets transform of spawnPositions children
        randomSpawn = (GameObject)((Transform)childs[Random.Range(0, childs.Length)]).gameObject; // randomly picks a childs transform

        return randomSpawn;
    }
}