private IEnumerable <PrismCollision> PotentialCollisions() { QuadTree quadtree = new QuadTree(new Rect(0, 0, 10, 10), 0, null); for (int i = 0; i < prisms.Count; i++) { Debug.Log("1"); prisms[i].check = false; quadtree.Addprism(prisms[i]); } foreach (PrismCollision check in QuadtreeRecursion(quadtree)) { yield return(check); } }