How to keep track of all objects of same type?

Questions & Answers
1

I want to have a list of TrailRenderer that keeps track of all the trail renderers so that I can do operations on all of them without using “FindObjectsOfType” (because I heard Find is slow). My question is: How do I get notified when a new trail Renderer is instantiated or is destroyed so that I know when to add or remove from the list? Is there a call-back function like “TrailRenderer.OnNewTrailRendererInstantiate?”

3

To clarify, you probably want something along these lines

//In your script that tracks all the trail renderers
public class TrailRendererManager : Monobehavior {
    public static List<TrailRenderer> trailList;

    void Awake() { 
        trailList = new List<TrailRenderer>();
    }
}

//Attached to every object with a trail renderer
public class TrailRendererInstance : Monobehavior {
    void Start(){ 
        TrailRendererManager.trailList.Add(GetComponent<TrailRenderer>());
    }
}
4

Currently on my game I’m using something along these lines. This takes care of the Add / Remove. If you want to be more specific, you can use OnDestroy instead of OnDisable

public class TrailRenderer : MonoBehaviour {
    private static List<TrailRenderer> _TrailRendererList = new List<TrailRenderer>();
    public static List<TrailRenderer> TrailRendererList {
        get {
            return _TrailRendererList;
        }
    }
    void OnEnable() {
        _TrailRendererList.Add(this);
    }

    void OnDisable() {
        _TrailRendererList.Remove(this);
    }
}
2

void Awake()
{
var trails = FindObjectsOfType();
}

trails would be an array with all the trailrenderers