CompactCalendar time = position.getTime();
if (time == null)
continue;
if (maximumTime == null || time.after(maximumTime))
maximumTime = time;
if (minimumTime == null || time.before(minimumTime))
minimumTime = time;
}
this.northEast = new SimpleNavigationPosition(maximumLongitude, maximumLatitude, maximumTime);
this.southWest = new SimpleNavigationPosition(minimumLongitude, minimumLatitude, minimumTime);
}