public iRoadSeg SegMinusOne(iRoadSeg seg) { int Idx = seg.Idx - 1; if (Idx == -1) { return(_Segments.Last()); } else { return(_Segments[Idx]); } }
public iRoadSeg SegPlusOne(iRoadSeg seg) { int Idx = seg.Idx + 1; if (Idx == _Segments.Count) { return(_Segments[0]); } else { return(_Segments[Idx]); } }