public Intersection getClosest(Ray r) throws Exception {
		Intersection closest = null;
		for (Entity o : objects) {
			Intersection p = o.findIntersect(r);
			if (p == null) {
				continue;
			}
			if (closest == null) {
				closest = p;
				continue;
			}
			if (p.getDistance() < closest.getDistance()) {
				closest = p;
			}
		}
		return closest;
	}