/// <summary>
/// Computes the distance from the point to the segment. The return
/// value is in units of sqrt(lat^2 + long^2) in WGS84 coordinates.
/// </summary>
/// <returns>The distance to the point in units of sqrt(lat^2 + long^2).</returns>
/// <param name="point">Point on Earth.</param>
public double DistanceToPoint(GeoCoordinates point)
{
Vector2 p1 = Endpoint1.ToVector2();
Vector2 p2 = Endpoint2.ToVector2();
if (CrossesMeridianRightOfP1)
{
p2 += new Vector2(360, 0);
Vector2 pointRepr1 = point.ToVector2();
Vector2 pointRepr2 = pointRepr1 + new Vector2(360, 0);
double dist1 = Geometry2d.PointToSegmentDistance(p1, p2, pointRepr1);
double dist2 = Geometry2d.PointToSegmentDistance(p1, p2, pointRepr2);
return(Math.Min(dist1, dist2));
}
else if (CrossesMeridianLeftOfP1)
{
p2 -= new Vector2(360, 0);
Vector2 pointRepr1 = point.ToVector2();
Vector2 pointRepr2 = pointRepr1 - new Vector2(360, 0);
double dist1 = Geometry2d.PointToSegmentDistance(p1, p2, pointRepr1);
double dist2 = Geometry2d.PointToSegmentDistance(p1, p2, pointRepr2);
return(Math.Min(dist1, dist2));
}
else
{
return(Geometry2d.PointToSegmentDistance(p1, p2, point.ToVector2()));
}
}
public void DistanceToPointForSmallSegmentNotCrossingPrimeMeridian()
{
Vector2 point = new Vector2(1, 1);
Vector2 segA = new Vector2(-1, 0);
Vector2 segB = new Vector2(1, 0);
GeoCoordinates geoPoint = new GeoCoordinates(point.y, point.x);
GeoSegment geoSegment = new GeoSegment(
new GeoCoordinates(segA.y, segA.x),
new GeoCoordinates(segB.y, segB.x));
Assert.Equal(
Geometry2d.PointToSegmentDistance(segA, segB, point),
geoSegment.DistanceToPoint(geoPoint),
6);
}