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OnCollisionEnter not working

Discussion in 'Scripting' started by Mike L, Aug 3, 2011.

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  1. Mike L

    Mike L

    Joined:
    Sep 14, 2010
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    for some reason, this isn't working
    Code (csharp):
    1. void OnCollisionEnter (Collision hit) {
    2.     //if (hit.impactForceSum.magnitude > 10) {
    3.         Debug.Log("yay");
    4.     //}
    5. }
    its not registering the collision and saying yay in the console

    Edit: i forgot to tell you, its a capsule collider, and isTrigger is false
     
  2. zine92

    zine92

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    Is your other collider having rigidbody or any rigidbody attached to this collider. On colllision will only be called when one of the colliders have a rigidbody. Take a look at this. OnCollisionEnter.
     
    Last edited: Aug 3, 2011
  3. Mike L

    Mike L

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    ah, thats what is missing, thanks man
     
  4. Mike L

    Mike L

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    new problem, now its colliding with something i really dont want it to, ill try something and see if it works in the future...
     
  5. DanielQuick

    DanielQuick

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  6. Mike L

    Mike L

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    Yeah, i know about that, but if i try that, that takes more time to set up, i just decided to do it a bit differently
     
  7. Rafes

    Rafes

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    If you set the other collider to be a trigger only, it should work, if I understand your issue correctly. That is what the isTrigger is for.
    You may also need to set the new collider to isKinematic, though I don't see that changing the way the collider works, just to stop it from being processed by PhysX.
     
  8. msue2

    msue2

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    Another possible issue: The order of Rigidbody and Collider components on the game object. This requirement is not documented on the OnTriggerEnter page. Tested on 2017.4.

    The Rigidbody component must be added first, followed by the Collider component. The order of already added components can be changed in the inspector cogwheel dropdown with "Move Up"/"Move down".
     
  9. megabrobro

    megabrobro

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    You are a hero today sir
     
    GhostSlayer44 likes this.
  10. rodrigoschmidtgodinho

    rodrigoschmidtgodinho

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    your collider is too small. too small.Increase your size.
     
  11. ApocalypseZ

    ApocalypseZ

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    Might be a silly answer, but sometimes the little things are missed.

    I ended up on this post and couldn't figure it out. Come to find out, I forgot to attach the script to my projectile gameObject.

    Make sure your script is attached! =D
     
  12. dkaloger

    dkaloger

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    also make sure the rigidbody is not kinematic
     
  13. Grant-king7432

    Grant-king7432

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    Hey all, I have been having similar issues and found this page. For me I had a prefab that had child objects(Camera, Lamp, Cylinder). I had my script on the Parent prefab and OnCollisionEnter was not registering....It turns out the Rigidbody was not registering with the floor because the Ridgidbody was on the Cylinder child object....not the parent prefab. Even with dragging the Cylinder Child object into the inspector as the Rigidbody to use, still no register with the ground....I put a small script on the Cylinder Child object and dragged in the same Rigidbody and walla....Now it is registering as touching the ground.
     
  14. steveh2112

    steveh2112

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    i know this is old but i just found a solution to a problem in my code, i had OnCollisionEnter in a script attached the parent of the thing that was getting the collision, not the thing that was getting the collision, so it didn't work.

    obvious really but if you are getting frustrated, check you have the script attached to the correct object
     
    taylor_unity867 likes this.
  15. Ryker404

    Ryker404

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    Thank You!
     
  16. B7LLF

    B7LLF

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    I just had this when following a tutorial, turns out that the gameObject.name is important and needs to match your object that is doing the collision ('player-ball' in my case). I had just typed the name in wrong.
     
    charmseer likes this.
  17. shaktip2014

    shaktip2014

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    i just want to say. Love u bro
     
  18. jakim28

    jakim28

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    None of these work for me :(
     
  19. JakubJWFA

    JakubJWFA

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    Another possible issue, even if a bit silly:
    If you make 2D game make sure you use void OnCollisionEnter2D(Collision2D collision) not OnCollisionEnter.
     
    Last edited: Dec 27, 2021
  20. dhtpdud528

    dhtpdud528

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    I'm the luckiest person in the world.
    because This is the only article you have written. and it has been less than 24 hours since you wrote it.
    For me, this is a very simple and accurate diagnosis.

    You saved my time. TY.
     
    Last edited: Dec 28, 2021
  21. AttemptingToMakeAGame

    AttemptingToMakeAGame

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    This was the solution that actually worked for me thank you!!!!!!!
     
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