ArcObjects Library Reference (Geometry)

IConstructPoint.ConstructOffset Method

Constructs a point distance units along the input curve and offset units perpendicularly away from it.

[Visual Basic .NET]
Public Sub ConstructOffset ( _
    ByVal curve As ICurve, _
    ByVal extension As esriSegmentExtension, _
    ByVal distance As Double, _
    ByVal asRatio As Boolean, _
    ByVal Offset As Double _
)

[C#]
public void ConstructOffset (
    ICurve curve,
    esriSegmentExtension extension,
    double distance,
    bool asRatio,
    double Offset
);

[C++]
HRESULT ConstructOffset(
  ICurve* curve,
  esriSegmentExtension extension,
  double distance,
  VARIANT_BOOL asRatio,
  double Offset
);

[C++]

Parameters
curve 

  curve is a parameter of type ICurve
extension 

  extension is a parameter of type esriSegmentExtension
distance 
  distance is a parameter of type double
asRatio 
  asRatio is a parameter of type VARIANT_BOOL
Offset 
  Offset is a parameter of type double

Product Availability

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

Remarks

A positive Offset distance will create a point on the right side of the curve and a negative offset will create a point on the left side of the curve.

ConstructPoint ConstructOffset Example

Set the asRatio flag to be True if you want the distance to be a ratio of the curve length. If set to True, then a distance of 0.5 will be equal to half of the curve length (i.e. 50%).

[C#]

//This example demonstrates how to use IConstructPoint.ConstructOffset method
private void ConstructOffset()
{
    IPoint[] points=new IPoint[4];
    for (int i=0; i < 4; i++)
    {
        points[i]=new PointClass();
    }
    points[0].PutCoords(0, 0);
    points[1].PutCoords(10, 0);
    points[2].PutCoords(20, 0);
    points[3].PutCoords(30, 0);
    IPointCollection polyline=new Polyline();
    //helper class to solve C-Style Array usage in COM classes
    IGeometryBridge geometryBride=new GeometryEnvironmentClass();
    geometryBride.AddPoints(polyline as IPointCollection4, ref points);

IConstructPoint constructionPoint=new PointClass();
//The spatial reference should be set on the new point here (Code skipped)

    //Example 1: Distance No ratio, Positive offset
    constructionPoint.ConstructOffset(polyline as ICurve, esriSegmentExtension.esriNoExtension, 15, false, 5);
    IPoint outPutPoint1=constructionPoint as IPoint;
    System.Windows.Forms.MessageBox.Show("Output point : " + outPutPoint1.X + " , " + outPutPoint1.Y);
    //Output point : 15 , -5
    //*********************************************
    //Example 2: Distance as ratio, Positive offset
    constructionPoint.ConstructOffset(polyline as ICurve, esriSegmentExtension.esriNoExtension, 0.5, true, 5);
    IPoint outPutPoint2=constructionPoint as IPoint;
    System.Windows.Forms.MessageBox.Show("Output point : " + outPutPoint2.X + " , " + outPutPoint2.Y);
    //Output point : 15 , -5
    //*********************************************
    //Example 3: Distance No ratio, Negative offset
    constructionPoint.ConstructOffset(polyline as ICurve, esriSegmentExtension.esriNoExtension, 15, false, -5);
    IPoint outPutPoint3=constructionPoint as IPoint;
    System.Windows.Forms.MessageBox.Show("Output point : " + outPutPoint3.X + " , " + outPutPoint3.Y);
    //Output point : 15 , 5
}

[Visual Basic .NET]

   'This example demonstrates how to use IConstructPoint::ConstructOffset
    Sub ConstructOffset()
        Dim ptc As IPointCollection, pt(3) As IPoint, i As Long
        Dim pconsPoint As IConstructPoint, ptout As IPoint
        ptc=New Polyline
        'The spatial reference should be set on the polyline here (Code skipped)
        For i=0 To 3
            pt(i)=New Point
        Next
        pt(0).PutCoords(0, 0)
        pt(1).PutCoords(10, 0)
        pt(2).PutCoords(20, 0)
        pt(3).PutCoords(30, 0)
        ptc.AddPoints(4, pt(0))
        'The spatial reference should be set on the new point here (Code skipped)
        '*********************************************
        'Example 1: Distance No ratio, Positive offset
        pconsPoint=New Point
        pconsPoint.ConstructOffset(ptc, esriSegmentExtension.esriNoExtension, 15, False, 5)
        ptout=pconsPoint
        Debug.Print("Output point : " & ptout.X & " , " & ptout.Y)
        'Output point : 15 , -5
        '*********************************************
        'Example 2: Distance as ratio, Positive offset
        pconsPoint=New Point
        pconsPoint.ConstructOffset(ptc, esriSegmentExtension.esriNoExtension, 0.5, True, 5)
        ptout=pconsPoint
        Debug.Print("Output point : " & ptout.X & " , " & ptout.Y)
        'Output point : 15 , -5
        '*********************************************
        'Example 3: Distance No ratio, Negative offset
        pconsPoint=New Point
        pconsPoint.ConstructOffset(ptc, esriSegmentExtension.esriNoExtension, 15, False, -5)
        ptout=pconsPoint
        Debug.Print("Output point : " & ptout.X & " , " & ptout.Y)
        'Output point : 15 , 5
    End Sub

IConstructPoint.ConstructOffset Method

Product Availability

Remarks

See Also