code: @Override
  	@Pure
  	public GraphIterator<RoadSegment, RoadConnection> depthIterator(
  			double depth, double position_from_starting_point,
  			RoadConnection starting_point, boolean allowManyReplies,
  			boolean assumeOrientedSegments) {
  		RoadConnection pt = starting_point.getWrappedRoadConnection();
  
  		if ((pt == null)
  				|| ((!getBeginPoint(StandardRoadConnection.class).equals(pt))
  						&& (!getEndPoint(StandardRoadConnection.class).equals(pt)))) {
  			pt = getBeginPoint(StandardRoadConnection.class);
  		}
  
  		return new DistanceBasedRoadNetworkIterator(
  				getRoadNetwork(),
  				depth, position_from_starting_point,
  				this, pt,
  				allowManyReplies, assumeOrientedSegments);
  	}
docs: -------------------------------------------------