Adding gameObjects colliding with a trigger to an array

Questions & Answers
1

My issue is that i am trying to add everything that collides with a certain trigger to an array, and htis part works to my knowledge (although there may be problems with the values it adds) the biggest probelm is making sure it doesn;t add the same thing twice.

My script is as follows:

var colliders = new Array();

function OnTriggerEnter (other : Collider)
{
	if (!colliders.contains(other.gameObject))
    {
		colliders.Add(other.gameObject);
	}
}

function Update()
{
	print(colliders);
}

However with the addition of the “if(!colliders.contains(other.gameObject))” line it doesn’t add them to the array anymore.

Any ideas why this is?
Thanks, Tom.

2

If that’s the exact code and you don’t have #pragma strict at the top of the file then it’s probably because you’ve used contains with a lowercase “c” rather than “Contains”.

However you’d be much better off using a HashSet (which is O(1) for detecting an existing entry and ensuring only one of each type can be in there compared to the O(n) operation of Contains).

 import System.Collections.Generic;

 var collders = new HashSet.<Collider>();

You should never really use Array - always use a generic collection (e.g. List) as they are much better. There’s info here.

3

You are using javascript, so I don’t have code for you, but I use HashSet.
In C# you include the using System.Collections.Generic;

Hashset is like a list but provides uniqueness. I use it for exactly what your are using it for.
Remember to remove it when OnTriggerExit() is called.