Why does this have to be in an update method?

Archived Forums Questions & Answers
1

All I wanted to do was move the centre of mass of a rigid body, but it wouldn’t work unless I put it in an update, like this.

using System.Collections;

public class CoM : MonoBehaviour {


void Update() {
        rigidbody.centerOfMass = new Vector3(0, 0, -2);
    }
}

I just don’t see why you can’t put it in a custom method like “void MoveCenter()”.

Btw I’m learning Unity3d and C# at the same time.

1 Answer

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instead of placing it in Update(), place it in Start()

void Start() {
   rigidbody.centerOfMass = new Vector3(0, 0, -2);
}

Update() gets called every frame, Start() only once in the beginning. If you would place it in MoveCenter() it would never get called.

Ah. Thanks. I guess the Unity Engine doesn't call custom methods. That's why we have start?

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If you want custom methods to be called, you call them yourself from Start(),Awake(),Update().. depends on what behaviour you want. If I helped you out, please click the check-mark on the left of my answer. :)

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Yes thanks. I understand how this works now.

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Unity does not directly call custom methods, because it doesn't even know they exist! You have to call them yourself.

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Syclamoth - Yes I get it now, finally! It makes sense. I didn't before - I was just doing things parrot fashion, but now things are starting to fall into place.

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