API Documentation > CorelDRAW > 2025-v26 > SubPath > IVGSubPath
SubPath.GetCurvatureAt method
Gets the Curve's Curvature at the current subpath
Syntax:
Function GetCurvatureAt(Optional ByVal Offset As Double = 0.5, Optional ByVal OffsetType As cdrSegmentOffsetType = cdrRelativeSegmentOffset) As Double
Parameters:
Name Type Description
Offset
Double
Specifies the offset, in document units. 5.
OffsetType
Specifies the offset type of the point, and returns cdrSegmentOffsetType.
Remarks:
The GetCurvatureAt method returns the curvature of a subpath at a given point. The value of the curvature is the inverse of curvature radius, and it depends on the current document units.
Examples:
The following VBA example draws a circle that touches the selected curve at the point that is 25% of the length of its first subpath and that has the same curvature as the curve in this point (thereby showing the curvature radius).
Sub Test()
Dim c As Double, r As Double
Dim x As Double, y As Double, pa As Double
Dim sp As SubPath
Set sp = ActiveShape.Curve.SubPaths(1)
c = sp.GetCurvatureAt(0.25, cdrRelativeSegmentOffset)
If Abs(c) < 0.00001 Then
  MsgBox "The curve is almost straight at this point", vbCritical
  Exit Sub
End If
sp.GetPointPositionAt x, y, 0.25, cdrRelativeSegmentOffset
pa = sp.GetPerpendicularAt(0.25, cdrRelativeSegmentOffset)
pa = pa * 3.1415926 / 180
r = 1 / c
x = x + r * Cos(pa)
y = y + r * Sin(pa)
ActiveLayer.CreateEllipse2 x, y, r 
End Sub