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ISegment.QueryCurvature Method (ArcObjects .NET 10.8 SDK)
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ISegment.QueryCurvature Method

Finds curvature and unit vector starting at point on segment and directed to embedded circle center.

[Visual Basic .NET]
Public Sub QueryCurvature ( _
    ByVal DistanceAlongCurve As Double, _
    ByVal asRatio As Boolean, _
    ByRef curvature As Double, _
    ByVal unitVector As ILine _
public void QueryCurvature (
    double DistanceAlongCurve,
    bool asRatio,
    ref double curvature,
    ref ILine unitVector
HRESULT QueryCurvature(
  double DistanceAlongCurve,
  System.Double* curvature,
  ILine* unitVector

DistanceAlongCurve is a parameter of type double asRatio
asRatio is a parameter of type bool curvature [out]
curvature is a parameter of type double* unitVector
unitVector is a parameter of type ILine*

Product Availability

Available with ArcGIS Engine, ArcGIS Desktop, and ArcGIS Server.


Returns the curvature at a specified distance along the segment.  The distance can be given explicitly or as a ratio of the entire length of the segment.  The curvature is returned as a Line representing a directional unit vector (in the direction going from the From Point to the To Point) and a double representing the magnitude of the vector of curvature.


The unit vector returned by QueryCurvature points toward the center of the circle that has the same first and second derivative at the queried point with a curvature value equal to 1 / Radius of that circle.

QueryCurvature Example

See Also

ISegment Interface