ArcObjects Library Reference (Geometry)  

IConstructCircularArc.ConstructTangentRadiusAngle Method

Constructs an arc with a common tangent to the input segment, a given radius and a central angle.

[Visual Basic .NET]
Public Sub ConstructTangentRadiusAngle ( _
    ByVal Segment As ISegment, _
    ByVal atStart As Boolean, _
    ByVal isCCW As Boolean, _
    ByVal inRadius As Double, _
    ByVal CentralAngle As Double _
)
[C#]
public void ConstructTangentRadiusAngle (
    ISegment Segment,
    bool atStart,
    bool isCCW,
    double inRadius,
    double CentralAngle
);
[C++]
HRESULT ConstructTangentRadiusAngle(
  ISegment* Segment,
  VARIANT_BOOL atStart,
  VARIANT_BOOL isCCW,
  double inRadius,
  double CentralAngle
);
[C++]

Parameters

Segment

  Segment is a parameter of type ISegment

atStart   atStart is a parameter of type VARIANT_BOOL isCCW   isCCW is a parameter of type VARIANT_BOOL inRadius   inRadius is a parameter of type double CentralAngle   CentralAngle is a parameter of type double

Product Availability

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

Description

Constructs a CircularArc given the Tangent Segment, the desired segment endpoint (the From Point), the desired orientation, the desired Radius, and the desired Central Angle.  The Central Angle is measured in radians.  A full CircularArc is constructed if the Central Angle is greater than 2*Pi.

Remarks

-isCCW stands for "is counter clockwise"

ConstructCircularArc Tangent Segment Example

[C#]
private void ConstructTangentRadiusAngle()
{
  IConstructCircularArc constructCircularArc = new CircularArcClass();
  ICircularArc circularArc = constructCircularArc as ICircularArc;
  
  IPoint fromPoint = new PointClass();
  fromPoint.PutCoords(100, 100);
  IPoint toPoint = new PointClass();
  toPoint.PutCoords(100, 400);
  ILine line = new LineClass();
  line.PutCoords(fromPoint, toPoint);
  //The angles should be in Radians (Radians = Degrees * PI/180)
  constructCircularArc.ConstructTangentRadiusAngle(line as ISegment, false, true, 50, Math.PI);
   
  String report = "Length : " + circularArc.Length + "\n" +
                  "Radius : " + circularArc.Radius + "\n" +
                  "Chord Height : " + circularArc.ChordHeight + "\n" +
                  "Central Angle (Rad) : " + circularArc.CentralAngle + "\n" +
                  "From Angle (Rad) : " + circularArc.FromAngle + "\n" +
                  "To Angle (Rad) : " + circularArc.ToAngle + "\n" +
                  "Center Point : " + circularArc.CenterPoint.X + " , " + circularArc.CenterPoint.Y + "\n" +
                  "From Point : " + circularArc.FromPoint.X + " , " + circularArc.FromPoint.Y + "\n" +
                  "To Point : " + circularArc.ToPoint.X + " , " + circularArc.ToPoint.Y;
  System.Windows.Forms.MessageBox.Show(report);
}
[Visual Basic .NET]

    Private Sub ConstructTangentRadiusAngle()
        Dim pConstructCircularArc As ESRI.ArcGIS.Geometry.IConstructCircularArc
        Dim pCArc As ESRI.ArcGIS.Geometry.ICircularArc
        Dim Pi As Double
        Dim pToPoint As ESRI.ArcGIS.Geometry.IPoint
        Dim pFromPoint As ESRI.ArcGIS.Geometry.IPoint
        Dim pLine1 As ESRI.ArcGIS.Geometry.ILine

        pConstructCircularArc = New ESRI.ArcGIS.Geometry.CircularArc
        pCArc = pConstructCircularArc
        Pi = 4 * Math.Atan(1) 'Calculate the value of pi.
        pFromPoint = New ESRI.ArcGIS.Geometry.Point
        pToPoint = New ESRI.ArcGIS.Geometry.Point
        pLine1 = New ESRI.ArcGIS.Geometry.Line
        pFromPoint.PutCoords(100, 100)
        pToPoint.PutCoords(100, 400)
        pLine1.PutCoords(pFromPoint, pToPoint)
        'The angles should be in Radians (Radians = Degrees * PI/180)
        pConstructCircularArc.ConstructTangentRadiusAngle(pLine1, False, True, 50, Pi)

        Debug.Print("Length : " & pCArc.Length)
        Debug.Print("Radius : " & pCArc.Radius)
        Debug.Print("Chord Height : " & pCArc.ChordHeight)
        Debug.Print("Central Angle (Rad) : " & pCArc.CentralAngle)
        Debug.Print("From Angle (Rad) : " & pCArc.FromAngle)
        Debug.Print("To Angle (Rad) : " & pCArc.ToAngle)
        Debug.Print("Center Point : " & pCArc.CenterPoint.X & " , " & pCArc.CenterPoint.Y)
        Debug.Print("From Point : " & pCArc.FromPoint.X & " , " & pCArc.FromPoint.Y)
        Debug.Print("To Point : " & pCArc.ToPoint.X & " , " & pCArc.ToPoint.Y)
    End Sub

See Also

IConstructCircularArc Interface | IConstructCircularArc.ConstructTangentRadiusAngle Method | IConstructCircularArc.ConstructTangentRadiusArc Method | IConstructCircularArc.ConstructTangentChordTangent Method | IConstructCircularArc.ConstructTangentRadiusChord Method | IConstructCircularArc.ConstructTangentChordArc Method | IConstructCircularArc.ConstructTangentRadiusTangent Method | IConstructCircularArc.ConstructTangentArcTangent Method | IConstructCircularArc.ConstructTangentAngleChord Method | IConstructCircularArc.ConstructTangentAngleTangent Method | IConstructCircularArc.ConstructTangentAndPoint Method | IConstructCircularArc.ConstructTangentAngleArc Method