public ArrayList<Sprite> getSprites(ArrayList<Sprite> SpriteCollector) {
		if (leaf) {
			for (Sprite p : sprites) {
				if (p == null) {
					break;
				}
				SpriteCollector.add(p);
			}
		} else {
			for (Rtree tree : subTrees) {
				SpriteCollector = tree.getSprites(SpriteCollector);
			}
		}
		return SpriteCollector;
	}