My spawner isn't working

Problem:
I’m trying to create a spawner that either instantiates a gameobject, and if not, will instantiate one item in its place.
For some reason it is sometimes spawning more than one item, or the gameobject and an item.

Question:
How can I adjust my code so that I’m not instantiating an item if a gameobject or item has already been created?

Current code:

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

public class RandomPositionSpawner : MonoBehaviour
{
    //public RoomCenter roomCenter;

    private GameObject spawnPoint;
    public GameObject[] spawnPoints;
    public GameObject objectToSpawn;
    private int spawnPointSelector;


    public static bool spawnAllowed;

    private GameObject tempGO;

    public bool shouldSpawnItems;
    public GameObject[] itemsToSpawn;
    public int itemDropPercentChance;
    private int randomItem;


    // Use this for initialization
    void Start()
    {

        Shuffle();




        spawnAllowed = true;

        SpawnObject();


    }

    public void Shuffle()
    {
        for (int i = 0; i < spawnPoints.Length; i++)
        {
            int rnd = Random.Range(0, spawnPoints.Length);
            tempGO = spawnPoints[rnd];
            spawnPoints[rnd] = spawnPoints[i];
            spawnPoints[i] = tempGO;
        }
    }


        void SpawnObject()
    {
        if (spawnAllowed)
        {

            Instantiate(objectToSpawn, spawnPoints[0].transform.position, Quaternion.identity);


            if (shouldSpawnItems)
            {



                for (int i = 1; i < spawnPoints.Length; i++)
                {


                    float dropChance = Random.Range(0f, 100f);

                    if (dropChance < itemDropPercentChance)
                    {
                        randomItem = Random.Range(0, itemsToSpawn.Length);

                        Instantiate(itemsToSpawn[randomItem], spawnPoints[i].transform.position, Quaternion.identity);
                    }

                }
            }

            spawnAllowed = false;
        }


    }

}

You must find a way to get the information you need in order to reason about what the problem is.

What is often happening in these cases is one of the following:

  • the code you think is executing is not actually executing at all
  • the code is executing far EARLIER or LATER than you think
  • the code is executing far LESS OFTEN than you think
  • the code is executing far MORE OFTEN than you think
  • the code is executing on another GameObject than you think it is

To help gain more insight into your problem, I recommend liberally sprinkling Debug.Log() statements through your code to display information in realtime.

Doing this should help you answer these types of questions:

  • is this code even running? which parts are running? how often does it run? what order does it run in?
  • what are the values of the variables involved? Are they initialized? Are the values reasonable?
  • are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

Knowing this information will help you reason about the behavior you are seeing.

You can also put in Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene

You could also just display various important quantities in UI Text elements to watch them change as you play the game.

If you are running a mobile device you can also view the console output. Google for how on your particular mobile target.

Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

Here’s an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

https://discussions.unity.com/t/839300/3

Turns out I had a duplicate script running so I was creating multiple spawners. Whoops. Thanks for the debug info drop!

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