Hi Will_Wang,

Thank you for your reply.

I know how to do it in the rough.But it seems doesn’t work,I don’t know what I missed.

```
Public Function moveBottomPointDown(ByVal sectionOfstCurve As Curve, ByVal doc As RhinoDoc) As Rhino.Geometry.Curve
Dim tmpPolyCurve As PolylineCurve
tmpPolyCurve = sectionOfstCurve.ToPolyline(5, 1, Math.PI, 0.1, 1, 0.1, 0.3, 10, True)
For i = 0 To tmpPolyCurve.PointCount - 1
If tmpPolyCurve.Point(i).Z <= 2.02 Then
Dim xFormMove As Transform
xFormMove = Transform.Translation(0, 0, -2.5)
tmpPolyCurve.Point(i).Transform(xFormMove)
'It seems doesn't work
Rhino.RhinoDoc.ActiveDoc.Objects.AddPoint(tmpPolyCurve.Point(i))
End If
Next
Return tmpPolyCurve
End Function
```

Best regards,

Hearts_j