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 louisebishop1 · Jan 29, 2013 at 05:59 AM · instantiatenullreferenceexceptiongunshoot

NullReferenceException firing bullets

I am making a paintball gun that fires at wherever the mouse is pointed. I am fairly new to Unity 3D. At present I have an android capsule game object which is a parent to my gun game object which in turn houses my bullet and spawn point. I am struggling with a NullReferenceException which is thrown on line 6 when I attempt to instantiate bullets.

 var clone : GameObject = Instantiate (BulletPrefab,

Here is my code which I currently have placed on my bullet

 var BulletPrefab :GameObject; 
 var force : float = 2000;
 
 function Update() { 
     if(Input.GetButtonDown("Fire1")) { 
     var clone : GameObject = Instantiate (BulletPrefab,
 
 GameObject.Find("spawnPoint").transform.position,
 
 Quaternion.identity);
 
 clone.rigidbody.AddForce(transform.forward * force);
 
 } }

I can't work out where I'm going wrong

Thanks,

Louise

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 CodeMasterMike · Jan 29, 2013 at 06:09 AM

I think that your code doesn't find the "spawnPoint" object that you are searching for. The best way to avoid NullReferenceException crashes, is to make sure that all your objects that you want to use, actually exists before trying to access their data.

 var BulletPrefab : GameObject; 
 var force : float = 2000;
 function Update() 
 { 
   if(Input.GetButtonDown("Fire1")) 
   { 
     var spawnPoint : GameObject = GameObject.Find("spawnPoint");
     var clone : GameObject = null;
 
     if(spawnPoint != null)
     {
       var spawnPosition : Vector3 = spawnPoint.transform.position;
       clone = Instantiate (BulletPrefab, spawnPosition, Quaternion.identity);
     }
   }
 }

The code above is not tested and I'm not used to writing Javascript code, so you might want to rewrite it a little, if its not working. But you see the basic idea of the code.

So before you Instantiate a clone, make sure that the spawnPoint object is actually found, so that you can get its position.

You could do a similar check with your created clone before you try to access its data, just to make sure it really is created by the Instantiate function.

Good luck!

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

10 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

Related Questions

Problem with Network.Instantiate on instantiating a bullet. 1 Answer

Shooting Script Instantiate Problems. Help? 0 Answers

Instanciate Object Problem for Shooting 2 Answers

Setting bullet instansiate direction? help? 1 Answer

Null Reference when trying to instantiate a prefab not in the scene 0 Answers


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