public static void Create(RoundaboutUtil raboutCalc)
        {
            NetInfo info       = PrefabUtil.SelectedPrefab;
            var     roundabout = new RaboutWraper(raboutCalc, info);

            roundabout.Create();
        }
        public RaboutWraper(RoundaboutUtil raboutCalc, NetInfo info)
        {
            _raboutCalc = raboutCalc;
            _junctions  = raboutCalc.GetJunctions();
            int n = _junctions.Count;

            if (n < 3)
            {
                Log.Info("Roundabout has too few junctions.");
                return;
            }
            Vector2 centerPoint = raboutCalc.CalculateCenter();

            _center   = new NodeWrapper(centerPoint, ControlCenter.Elevation);
            _slices   = new List <RaboutSlice>(n);
            _segments = new List <SegmentWrapper>(n - 1);

            for (int i = 0; i < n; ++i)
            {
                var i2    = (i + 1) % n;
                var slice = new RaboutSlice(
                    _junctions[i].Main2, _junctions[i].Minor,
                    _junctions[i2].Main1, _junctions[i2].Minor,
                    raboutCalc.SegmentList,
                    _center,
                    info);
                _slices.Add(slice);
                if (slice.IsValid)
                {
                    this.IsValid = true;
                }
            }

            if (ControlCenter.RoundaboutBridgeStyle == RoundaboutBridgeStyleT.Star)
            {
                return;
            }
            if (_slices.Count == 1)
            {
                return;
            }

            // get last valid slice.
            RaboutSlice slice_prev = null;

            for (int i = _slices.Count - 1; i >= 0; --i)
            {
                if (_slices[i].IsValid)
                {
                    slice_prev = _slices[i];
                    break;
                }
            }
            if (slice_prev == null)
            {
                return;
            }

            foreach (var slice in _slices)
            {
                if (!slice.IsValid)
                {
                    continue;
                }
                if (slice_prev.IsValid)
                {
                    var segment12 = slice_prev.segment_circle2;
                    var segment21 = slice.segment_circle1;
                    if (segment12 != null && segment21 != null)
                    {
                        var segment = new SegmentWrapper(
                            segment12.EndNode, segment21.EndNode,
                            -segment12.EndDir, -segment21.EndDir);
                        _segments.Add(segment);
                    }
                }
                slice_prev = slice;
            }
        }