How to randomly spawn a gameobject from a list/collection of GameObjects (Object pooled)

Please I have been trying to randomly spawn a gameobject from a list/collection of GameObjects implementing Object pooling technique for performance sake.

This is how far I have gotten:

http://bit.ly/2yFGhji

I was advised to implement inheritance..am really stuck.? Thanks

Code (CSharp):

1.  
2.     using System.Collections;
3.     using System.Collections.Generic;
4.     using UnityEngine;
5.  
6.  
7.  
8.     public class ObjectPoolRandomObject : MonoBehaviour {
9.         private float fireTime = .05f;//start Time of spawning
10.         [Tooltip("How long The Object will last in the scene eg" +
11.             "4 lasts 4 sec and 20 lasts 20 in scene Smaller rate for faster bullets. long for lasting vehicles")]
12.         public float fireRate = 2f; //Smaller rate for faster bullets. long for lasting vehicles
13.         public GameObject[] pooledObject;
14.         public int poolAmount = 5;
15.         List<GameObject> cars;
16.  
17.         void Start()
18.  
19.         {
20.  
21.             bullets = new List<GameObject>();
22.             for (int i = 0; i < poolAmount; i++)  
23.  
24.                 //GameObject obj = (GameObject)Instantiate(car); //POOLED 1 OBJECT (OK)
25.                 GameObject obj = (GameObject)Instantiate(pooledObject[Random.Range(0, pooledObject.Length)]);
26.                 obj.SetActive(false);
27.                 bullets.Add(obj);
28.             }
29.             InvokeRepeating("Fire", fireTime, fireRate);
30.  
31.         }
32.  
33.         void Fire()
34.  
35.         {
36.             for (int i = 0; i < bullets.Count; i++)
37.  
38.             {
39.                 bullets[i].transform.position = transform.position;
40.                 bullets[i].transform.rotation = transform.rotation;
41.                 bullets[i].SetActive(true);
42.                 break;
43.             }
44.         }
45.     }
46.  
47.      

The goal I am getting at is to spawn an infinite loop of cars that would not h performance since Destroy(gameObject) is highly performance on Android and deactivating clones will make it accumulate clones over time..



Thanks for reading

 

Well, first the Random.Range Needs to be set at (0,pooledObject.Length - 1).
Otherwise you can get IndexOutOfBounds exceptions.

Sencond, well what does happen when you execute your Code?

 

Not required, when you do Random.Range with ints the upper range is exclusive so subtracting 1 would mean it would never choose the last index in your collection.
https://docs.unity3d.com/ScriptReference/Random.Range.html

 

Errrr..I really appreciate you for trying but this didn't work... I guess I may have sacrifice performance and spawn and destroy

 

Object pooling is a tried and true method to implement something along these lines in a way that is performant.

Based on your code I suspect things are working...just not in the way that you thought.

First thing I'd do would be to do the SetActive() in your fire function first. I'm not 100% sure if a game objects transform can be updated if it's game object is actually disabled so it's worth trying.

Secondly, there are a number of things that could be causing problems...from the objects having rigid bodies thus gravity applied and vanishing off screen to the transform you used being in view of the camera. I'd set breakpoints in the code and debug what values are being assigned, and I'd also check the unity scene view....Hit pause in the editor after you "fire" choose a game object (which should be in your games heiarchy at runtime) then press F to focus on it... it could be well off screen or out of view of your game camera, or even on the wrong camera layer.

 

Above is the Expected Result but Car Instantiation and Destruction should be pooled for performance instead of Destroy()

Please click below to download error image when I copied code as above.. Been trying to tweak it for a while.

https://drive.google.com/file/d/1yoG1Otdx6h70GME2rJtN-Aw1I54ITg8A/view?usp=sharing

I really appreciate the time you are taking to tackle this for me

 

So Moderator...you may mark this as Solved..Thank @mikegeig for the support.

wouldn't have done this without you

For fellow newbies.. you may see below...

it has 2 sections..
-1st section to be attached to 2 or more diff objects so it will always move...

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class Instantiate : MonoBehaviour {
6.  
7.     // Use this for initialization
8.     void Start () {
9.        
10.     }
11.    
12.     // Update is called once per frame
13.     void Update () {
14.         transform.Translate(Vector3.forward);
15.     }
16. }
17.  

-2nd section ...
is the real Object Pooled Random spawner...to be added to a seperate emptyGameobject to spawn the above "moving" gameobject

Code (CSharp):

1. using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class ObjectPoolRandomSholaOginni : MonoBehaviour {
6.  
7.     private float fireTime = .05f;      //start Time of spawning
8.     [Tooltip("How long The Object will last in the scene eg 4 lasts 4 sec and 20 lasts 20 in scene Smaller rate for faster bullets. long for lasting vehicles")]
9.     public float fireRate = 2f;         //Smaller rate for faster bullets. long for lasting vehicles
10.     public int poolAmount = 5;          //Size of the object pool
11.     public GameObject[] randomObjects;  //Collection of random game objects to go into pool
12.     // GameObject[] pool;
13.     List<GameObject> pool;              //Actual pool
14.     int currentIndex = 0;               //The current index of the pool
15.     void Start()
16.     {
17.         pool = new List<GameObject>();
18.         for (int i = 0; i < poolAmount; i++)
19.         {
20.             int randomIndex = Random.Range(0, randomObjects.Length);
21.             GameObject obj = (GameObject)Instantiate(randomObjects[randomIndex]);
22.             obj.SetActive(false);
23.             pool.Add(obj);
24.         }
25.  
26.         InvokeRepeating("Fire", fireTime, fireRate);
27.     }
28.     void Fire()
29.     {
30.         pool[currentIndex].transform.position = transform.position;
31.         pool[currentIndex].transform.rotation = transform.rotation;
32.         pool[currentIndex].SetActive(true);
33.  
34.         if (++currentIndex >= pool.Count)// last issue
35.         {
36.             currentIndex = 0;
37.             for (int i = 0; i < pool.Count; i++)
38.             {
39.                 pool[i].gameObject.SetActive(false);
40.             }
41.             // pool[].gameObject.SetActive(false);
42.         }
43.     }
44.  
45. }
46.  

 

Thank you very much.