@Override
		public boolean apply(ICreature input) {
			if (input == observer) {
				return false;
			}
			double dirAngle = input.directionFormAPoint(observer.getPosition(),
					observer.getDirection());

			return abs(dirAngle) < (observer.getFieldOfView() / 2)
					&& observer.distanceFromAPoint(input.getPosition()) <= observer
							.getLengthOfView();

		}