ArcGIS Developer Help

IConstructCircularArc.ConstructTangentAngleArc Method

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

[Visual Basic .NET]
Public Sub ConstructTangentAngleArc ( _
    ByVal Segment As ISegment, _
    ByVal atStart As Boolean, _
    ByVal isCCW As Boolean, _
    ByVal CentralAngle As Double, _
    ByVal arcDistance As Double _
)

[C#]
public void ConstructTangentAngleArc (
    ISegment Segment,
    bool atStart,
    bool isCCW,
    double CentralAngle,
    double arcDistance
);

[C++]
HRESULT ConstructTangentAngleArc(
  ISegment* Segment,
  VARIANT_BOOL atStart,
  VARIANT_BOOL isCCW,
  double CentralAngle,
  double arcDistance
);

[C++]
Parameters
Segment 

  Segment is a parameter of type ISegment*
atStart 

  atStart is a parameter of type bool
isCCW 

  isCCW is a parameter of type bool
CentralAngle 

  CentralAngle is a parameter of type double
arcDistance 

  arcDistance 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 Central Angle, and the desired CircularArc Length. 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 ConstructTangentAngleArc()
{
  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.ConstructTangentAngleArc(line as ISegment, false, true, Math.PI, 100);
   
  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 ConstructTangentAngleArc()
        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 pPoint 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)
        pPoint = New ESRI.ArcGIS.Geometry.Point
        pPoint.PutCoords(200, 400)
        'The angles should be in Radians (Radians = Degrees * PI/180)
        pConstructCircularArc.ConstructTangentAngleArc(pLine1, False, True, Pi, 100)

        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

IConstructCircularArc.ConstructTangentAngleArc Method

Product Availability

Description

Remarks

See Also