//sorts a list of points form a polyline
public static List <Point2d> SortPoints(List <Point2d> pointList)
{
if (!ValidateObject.CheckPointList(pointList))
{
return(null);
}
Point2d cen = PolygonUtility.CentroidOfPoly(Polygon2d.ByPoints(pointList));
Vector2d vecX = new Vector2d(0, 100);
List <double> angList = new List <double>();
int[] indList = new int[pointList.Count];
for (int i = 0; i < pointList.Count; i++)
{
Vector2d CenterToPt = new Vector2d(cen, pointList[i]);
double dotValue = vecX.Dot(CenterToPt);
double angValue = Math.Atan2(CenterToPt.Y - vecX.Y, CenterToPt.X - vecX.X);
angList.Add(angValue);
indList[i] = i;
}
List <int> newIndexList = new List <int>();
newIndexList = BasicUtility.SortIndex(angList);
List <Point2d> sortedPointList = new List <Point2d>();
for (int i = 0; i < pointList.Count; i++)
{
sortedPointList.Add(pointList[newIndexList[i]]);
}
return(sortedPointList);
}
//sorts list of points by distance from a given point
public static List <Point2d> SortPointsByDistanceFromPoint(List <Point2d> ptList, Point2d testPoint)
{
List <Point2d> sortedPtList = new List <Point2d>();
List <double> distanceList = new List <double>();
List <int> indexList = new List <int>();
for (int i = 0; i < ptList.Count; i++)
{
distanceList.Add(PointUtility.DistanceBetweenPoints(ptList[i], testPoint));
}
indexList = BasicUtility.SortIndex(distanceList);
for (int i = 0; i < indexList.Count; i++)
{
sortedPtList.Add(ptList[indexList[i]]);
}
return(sortedPtList);
}