SetupBorderLine.cs

  void SetupBorderLine(){
    var perim = HexPerimeter.FindPerimeterLoop(selectedCity.influencedCells);

    var linePositions = HexPerimeter.GetLinePositions(perim);

    cityBorderLine.positionCount = linePositions.Count;

    for(var c = 0; c < linePositions.Count; c++){

      cityBorderLine.SetPosition(c, linePositions[c]);
    }

    cityBorderLine.gameObject.SetActive(true);
  }