GetNormalsAtM Method

Gets the line segments corresponding to the normal at the locations along the geometry where the specified M occurs.

Syntax

C#
Visual Basic (Declaration)

Polyline GetNormalsAtM( 
   Multipart multipart,
   double m,
   double length
)

Function GetNormalsAtM( _
   ByVal multipart As Multipart, _
   ByVal m As Double, _
   ByVal length As Double _
) As Polyline

Parameters

multipart: The multipart containing the M values. If the multipart is a polygon, then the boundary is used.
m: The M value at which to construct the normal line.
length: The length of the normal line. A positive value means the normal lines are on the right side of the multipart. A negative value means the normal lines are on the left side of the multipart.

Return Value

A polyline. Each part of the polyline is a normal line.

Exceptions

Exception	Description
System.ArgumentNullException	Multipart is null or empty.
System.InvalidOperationException	This geometry is not M-Aware.
System.NotImplementedException	Spatial reference of multipartis an image coordinate system.

Example

IList<MapPoint> inPoints = new List<MapPoint>()
{
  MapPointBuilder.CreateMapPoint(-3000, -2000, 0, 100),
  MapPointBuilder.CreateMapPoint(-3000, 0, 0, 200),
  MapPointBuilder.CreateMapPoint(-1000, 0, 0, 300),
  MapPointBuilder.CreateMapPoint(-1000, 2000, 0, 100),
  MapPointBuilder.CreateMapPoint(3000, 2000, 0, 200),
  MapPointBuilder.CreateMapPoint(3000, 0, 0, 300),
  MapPointBuilder.CreateMapPoint(1000, 0, 0, 100),
  MapPointBuilder.CreateMapPoint(1000, -2000, 0, 200),
  MapPointBuilder.CreateMapPoint(-3000, -2000, 0, 300)
};

Polygon polygon = PolygonBuilder.CreatePolygon(inPoints);
// polygon.HasM = true

Polyline polyline = GeometryEngine.Instance.GetNormalsAtM(polygon, 150, 100);
// polyline.PartCount = 5
// polyline.PointCount = 10
// polyline.HasM = false

ReadOnlyPartCollection parts = polyline.Parts;
ReadOnlySegmentCollection segments = parts[0];
LineSegment line = segments[0] as LineSegment;
// line.StartCoordinate = (-3000, -1000)
// line.EndCoordinate = (-2900, -1000)

segments = parts[1];
line = segments[0] as LineSegment;
// line.StartCoordinate = (-1000, 1500)
// line.EndCoordinate = (-900, 1500)

segments = parts[2];
line = segments[0] as LineSegment;
// line.StartCoordinate = (1000, 2000)
// line.EndCoordinate = (1000, 1900)

segments = parts[3];
line = segments[0] as LineSegment;
// line.StartCoordinate = (1500, 0)
// line.EndCoordinate = (1500, 100)

segments = parts[4];
line = segments[0] as LineSegment;
// line.StartCoordinate = (1000, -1000)
// line.EndCoordinate = (900, -1000)

Requirements

Target Platforms: Windows 10, Windows 8.1, Windows 7

Reference

IGeometryEngine Interface
IGeometryEngine Members