If Dts.Snap Then
            PictureViewer1.Invalidate(snapRect)
            If MouseTool = MouseToolEnm.Messen Then
                'Dim npt = Dts.NearestPoint(Dts.Canvas.TransForm(New Point(e.X, 
                ' e.Y), True))
                'If Not npt Is Nothing Then Dts.SnapPoint = 
                ' Dts.Canvas.TransForm(npt.Point.Round, False) : 
                ' snapRect.Location = Dts.SnapPoint Else Dts.SnapPoint = Nothing
                snapRect.Location = If(Dts.SnapPoint = Nothing, New Point(0, _
                  0), Dts.SnapPoint)
            End If
        End If

    'Friend Function NearestPoint(ByVal pt As System.Drawing.Point) As PointRow
    '    ' pt = Point in Bild, entsprechend der eingestellten Rotation
    '    If CurrPt Is Nothing OrElse CurrPt.Count = 0 Then Return Nothing
    '    Dim npt As PointRow = Nothing, nDist As Double = 10
    '    For i As Integer = 0 To CurrPt.Count - 1
    '        If Not npt Is Dts.Point.Last Then
    '            Dim pT1 As System.Drawing.Point = CurrPt(i).Point.Round
    '            Dim Abstand = pT1.Distance(pt)
    '            If Math.Abs(pT1.Distance(pt)) < nDist Then npt = CurrPt(i) : 
    ' nDist = Math.Abs(pT1.Distance(pt))
    '        End If
    '    Next
    '    Return npt
    'End Function

Danke für die Hilfe

Gruß Christian