GetNormalsAtM Method (IGeometryEngine)

In This Topic

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

Syntax

Visual Basic (Declaration)
C#

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

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

Parameters

multipart: The multipart containing the M-values. If the multipart is a polygon, then the boundary is used.
mValue: 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. If the input multipart is empty, then an empty polyline is returned.

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

Get line segments corresponding to the normal at the locations where the specified M values occur along the geometry - GetNormalsAtM

{
  IList<MapPoint> inPoints =
  [
    MapPointBuilderEx.CreateMapPoint(-3000, -2000, 0, 100),
MapPointBuilderEx.CreateMapPoint(-3000, 0, 0, 200),
MapPointBuilderEx.CreateMapPoint(-1000, 0, 0, 300),
MapPointBuilderEx.CreateMapPoint(-1000, 2000, 0, 100),
MapPointBuilderEx.CreateMapPoint(3000, 2000, 0, 200),
MapPointBuilderEx.CreateMapPoint(3000, 0, 0, 300),
MapPointBuilderEx.CreateMapPoint(1000, 0, 0, 100),
MapPointBuilderEx.CreateMapPoint(1000, -2000, 0, 200),
MapPointBuilderEx.CreateMapPoint(-3000, -2000, 0, 300)
  ];

  polygon = PolygonBuilderEx.CreatePolygon(inPoints);
  // polygon.HasM = true

  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 11 Home, Pro, Enterprise (64 bit)

ArcGIS Pro version: 3.0 or higher.

Reference

IGeometryEngine Interface
IGeometryEngine Members

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