i am trying to find a way to split a line by using an intersection
point already known. So the function must return two line segments.
The code doen't work. seperationOnIndex  is always -1.
Any ideas?
I am using sharpmap v0.9

Private Function SplitGeometryLineToTwoParts( lineToSplit As
GisSharpBlog.NetTopologySuite.Geometries.Geometry  , splitPoint As
GisSharpBlog.NetTopologySuite.Geometries.Geometry )

Dim splitPointCoordinate As ICoordinate = splitPoint.Coordinate

Dim seperationOnIndex As Integer = -1
For CoordIndex As Integer = 0 To
lineToSplit.Coordinates.Length - 2
Dim coord1 As ICoordinate = lineToSplit.Coordinates
(CoordIndex)
Dim coord2 As ICoordinate = lineToSplit.Coordinates
(CoordIndex + 1)

Dim rli As New
GisSharpBlog.NetTopologySuite.Algorithm.RobustLineIntersector
'NonRobustLineIntersector()
rli.ComputeIntersection(splitPointCoordinate, coord1,
coord2)
Dim intNum As Integer = rli.IntersectionNum
Dim check As Boolean = rli.IsIntersection
(splitPointCoordinate)

If rli.IsInteriorIntersection Then
seperationOnIndex = CoordIndex
End If
If intNum <> 0 Then
seperationOnIndex = CoordIndex
End If
If check Then
seperationOnIndex = CoordIndex
End If
If rli.HasIntersection Then
seperationOnIndex = CoordIndex
End If
Next

If seperationOnIndex = -1 Then
' MsgBox("What's the error?")
Exit Sub
End If

'-------------------------------------------------------------
Dim myLeftCoords As New List(Of GeoAPI.Geometries.ICoordinate)
Dim myRightCoords As New List(Of
GeoAPI.Geometries.ICoordinate)
'add the intersection point at  the beginning of myRightCoords
For CoordIndex As Integer = 0 To
lineToSplit.Coordinates.Length - 1
Dim coord As GeoAPI.Geometries.ICoordinate =
lineToSplit.Coordinates(CoordIndex)

'myLeftCoords should include the coordinates from 0 up to
and including seperationIndex
If CoordIndex <= seperationOnIndex Then
End If

'myRightCoords should include all the coordinates Greater
than separationIndex
If CoordIndex > seperationOnIndex Then
End If
Next
'-------------------------------------------------------------

'the end of myLeftCoords