Wayback Machinekoobas.hobune.stream
May JUN Jul
Previous capture 13 Next capture
2021 2022 2023
1 capture
13 Jun 22 - 13 Jun 22
sparklines
Close Help
  • Products
  • Solutions
  • Made with Unity
  • Learning
  • Support & Services
  • Community
  • Asset Store
  • Get Unity

UNITY ACCOUNT

You need a Unity Account to shop in the Online and Asset Stores, participate in the Unity Community and manage your license portfolio. Login Create account
  • Blog
  • Forums
  • Answers
  • Evangelists
  • User Groups
  • Beta Program
  • Advisory Panel

Navigation

  • Home
  • Products
  • Solutions
  • Made with Unity
  • Learning
  • Support & Services
  • Community
    • Blog
    • Forums
    • Answers
    • Evangelists
    • User Groups
    • Beta Program
    • Advisory Panel

Unity account

You need a Unity Account to shop in the Online and Asset Stores, participate in the Unity Community and manage your license portfolio. Login Create account

Language

  • Chinese
  • Spanish
  • Japanese
  • Korean
  • Portuguese
  • Ask a question
  • Spaces
    • Default
    • Help Room
    • META
    • Moderators
    • Topics
    • Questions
    • Users
    • Badges
  • Home /
avatar image
0
Question by franchar · Jan 06, 2021 at 09:46 PM · pooling

The Object you want to instantiate is null when using pool system

Hello, I created a pool system for bullets. When I try to instantiate a bullet it tells me "The Object you want to instantiate is null"

Here is the script for the pool system

 public class BulletPool : MonoBehaviour
 {
     public static BulletPool instance;
     [SerializeField]  GameObject bulletPrefab;
     Queue<GameObject> bullets;
 
     void Start()
     {
         if (bulletPrefab == null)
         {
             Debug.Log("error null");
         }
 
         if (instance == null)
         {
             instance = new BulletPool();
             instance.bullets = new Queue<GameObject>();
         }
     }
 
     public void AddToQueue(GameObject bullet)
     {
         bullet.SetActive(false);
         instance.bullets.Enqueue(bullet);
     }
 
     public GameObject GetBullet()
     {
         GameObject bullet;
         if (instance.bullets.Count > 0)
             bullet = instance.bullets.Dequeue();
         else
             bullet = Instantiate(bulletPrefab); // that's where the error is
         return bullet;
     }
 }

alt text

I added the prefab bullet to the script.

Anybody see what is wrong? Thank you for your help!

screenshot-2021-01-06-144331.png (6.9 kB)
Comment
Add comment
10 |3000 characters needed characters left characters exceeded
▼
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Viewable by all users

1 Reply

· Add your reply
  • Sort: 
avatar image
0

Answer by unity_ek98vnTRplGj8Q · Jan 06, 2021 at 10:47 PM

You actually have two instances of BulletPool. The first instance is the one that is attached to your game object. You make a second instance which you have called "instance", and this is the one that is throwing the error because it does not have the reference to the bullet prefab, while your first one does. To fix it, just change

          if (instance == null)
          {
              instance = new BulletPool();
              instance.bullets = new Queue<GameObject>();
          }

to

              if (instance == null)
              {
                  instance = this;
                  instance.bullets = new Queue<GameObject>();
              }

or something along those lines, whatever you want to to make sure that you only have the 1 instance of bullet pool.

Comment
Add comment · Share
10 |3000 characters needed characters left characters exceeded
▼
  • Viewable by all users
  • Viewable by moderators
  • Viewable by moderators and the original poster
  • Advanced visibility
Viewable by all users

Your answer

Hint: You can notify a user about this post by typing @username

Up to 2 attachments (including images) can be used with a maximum of 524.3 kB each and 1.0 MB total.

Follow this Question

Answers Answers and Comments

111 People are following this question.

avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image avatar image

Related Questions

Pooling object performs the same or worse than instantiate/destroy? 1 Answer

Optimising for mobile - Instantiate 1 Answer

My game lags on iOS devices and not android 0 Answers

How to reset a prefab used in object pool ? 2 Answers

Best performance for mass object movement 1 Answer


Enterprise
Social Q&A

Social
Subscribe on YouTube social-youtube Follow on LinkedIn social-linkedin Follow on Twitter social-twitter Follow on Facebook social-facebook Follow on Instagram social-instagram

Footer

  • Purchase
    • Products
    • Subscription
    • Asset Store
    • Unity Gear
    • Resellers
  • Education
    • Students
    • Educators
    • Certification
    • Learn
    • Center of Excellence
  • Download
    • Unity
    • Beta Program
  • Unity Labs
    • Labs
    • Publications
  • Resources
    • Learn platform
    • Community
    • Documentation
    • Unity QA
    • FAQ
    • Services Status
    • Connect
  • About Unity
    • About Us
    • Blog
    • Events
    • Careers
    • Contact
    • Press
    • Partners
    • Affiliates
    • Security
Copyright © 2020 Unity Technologies
  • Legal
  • Privacy Policy
  • Cookies
  • Do Not Sell My Personal Information
  • Cookies Settings
"Unity", Unity logos, and other Unity trademarks are trademarks or registered trademarks of Unity Technologies or its affiliates in the U.S. and elsewhere (more info here). Other names or brands are trademarks of their respective owners.
  • Anonymous
  • Sign in
  • Create
  • Ask a question
  • Spaces
  • Default
  • Help Room
  • META
  • Moderators
  • Explore
  • Topics
  • Questions
  • Users
  • Badges