public bool ContainsPosition(PolygonPoint p)
{
int n = this.Points.Count();
if (n <= 0)
{
return false;
}
List<PolygonPoint> v = Points.ToList();
v.Add(new PolygonPoint { Lat = v[0].Lat, Lon = v[0].Lon });
int wn = 0; // the winding number counter
// loop through all edges of the polygon
for (int i = 0; i < n; i++)
{ // edge from V[i] to V[i+1]
if (v[i].Lat <= p.Lat)
{ // start y <= P.y
if (v[i + 1].Lat > p.Lat) // an upward crossing
if (isLeft(v[i], v[i + 1], p) > 0) // P left of edge
++wn; // have a valid up intersect
}
else
{ // start y > P.y (no test needed)
if (v[i + 1].Lat <= p.Lat) // a downward crossing
if (isLeft(v[i], v[i + 1], p) < 0) // P right of edge
--wn; // have a valid down intersect
}
}
return wn != 0;
}
private static int isLeft(PolygonPoint P0, PolygonPoint P1, PolygonPoint P2)
{
double calc = ((P1.Lon - P0.Lon) * (P2.Lat - P0.Lat)
- (P2.Lon - P0.Lon) * (P1.Lat - P0.Lat));
if (calc > 0)
{
return(1);
}
else if (calc < 0)
{
return(-1);
}
else
{
return(0);
}
}
public bool ContainsPosition(PolygonPoint p)
{
int n = this.Points.Count();
if (n <= 0)
{
return(false);
}
List <PolygonPoint> v = Points.ToList();
v.Add(new PolygonPoint {
Lat = v[0].Lat, Lon = v[0].Lon
});
int wn = 0; // the winding number counter
// loop through all edges of the polygon
for (int i = 0; i < n; i++)
{ // edge from V[i] to V[i+1]
if (v[i].Lat <= p.Lat)
{ // start y <= P.y
if (v[i + 1].Lat > p.Lat) // an upward crossing
{
if (isLeft(v[i], v[i + 1], p) > 0) // P left of edge
{
++wn; // have a valid up intersect
}
}
}
else
{ // start y > P.y (no test needed)
if (v[i + 1].Lat <= p.Lat) // a downward crossing
{
if (isLeft(v[i], v[i + 1], p) < 0) // P right of edge
{
--wn; // have a valid down intersect
}
}
}
}
return(wn != 0);
}
public Polygon FromPointList(string name, string pointList)
{
pointList = pointList.TrimStart('\n', '\t');
pointList = pointList.TrimEnd('\n', '\t');
var points = pointList.Split(new String[] { " " }, StringSplitOptions.RemoveEmptyEntries);
CultureInfo ci = new CultureInfo("en-US");
var list = new List <PolygonPoint>(points.Length);
for (int i = 0; i < points.Length; i++)
{
var p = points[i].Split(new String[] { "," }, StringSplitOptions.RemoveEmptyEntries);
if (p.Length < 2 || p.Length > 3)
{
throw new Exception("Invalid polygon // invalid point data");
}
PolygonPoint pp = new PolygonPoint();
pp.Lon = double.Parse(p[0], ci);
pp.Lat = double.Parse(p[1], ci);
if (p.Length == 3)
{
pp.Alt = double.Parse(p[2], ci);
}
list.Add(pp);
}
if (!list.First().Equals(list.Last()))
{
throw new Exception("Invalid polygon // First does not equal Last");
}
return(new Polygon()
{
Points = list, Name = name
});
}
public double DistanceTo(PolygonPoint p)
{
return(Math.Pow(this.Lat - p.Lat, 2) + Math.Pow(this.Lon - p.Lon, 2));
}
private static int isLeft(PolygonPoint P0, PolygonPoint P1, PolygonPoint P2)
{
double calc = ((P1.Lon - P0.Lon) * (P2.Lat - P0.Lat)
- (P2.Lon - P0.Lon) * (P1.Lat - P0.Lat));
if (calc > 0)
return 1;
else if (calc < 0)
return -1;
else
return 0;
}
public double DistanceTo(PolygonPoint p)
{
return (Math.Pow(this.Lat - p.Lat, 2) + Math.Pow(this.Lon - p.Lon, 2));
}
public Polygon FromPointList(string name, string pointList)
{
pointList = pointList.TrimStart('\n', '\t');
pointList = pointList.TrimEnd('\n', '\t');
var points = pointList.Split(new String[] { " " }, StringSplitOptions.RemoveEmptyEntries);
CultureInfo ci = new CultureInfo("en-US");
var list = new List<PolygonPoint>(points.Length);
for (int i = 0; i < points.Length; i++) {
var p = points[i].Split(new String[] { "," }, StringSplitOptions.RemoveEmptyEntries);
if (p.Length < 2 || p.Length > 3) {
throw new Exception("Invalid polygon // invalid point data");
}
PolygonPoint pp = new PolygonPoint();
pp.Lon = double.Parse(p[0], ci);
pp.Lat = double.Parse(p[1], ci);
if (p.Length == 3) {
pp.Alt = double.Parse(p[2], ci);
}
list.Add(pp);
}
if (!list.First().Equals(list.Last())) {
throw new Exception("Invalid polygon // First does not equal Last");
}
return new Polygon() { Points = list, Name = name };
}
