There was an order of operation issue with your compassPoint calculation.
degrees Mod 360 will give you the degress on the compass you're looking for. (750.0 is really 30.0 etc.)
If you're looking to give an option for 32, 16, 8, 4 points you should be able multiply your point number by 32/number of points to get the correct value out of the Enum. Haven't tested it exhaustively but it worked with several values using 4 and 8 points.
Code:
Public Enum CardinalPoints
N
NbE
NNE
NEbN
NE
NEbE
ENE
EbN
E
EbS
ESE
SEbE
SE
SEbS
SSE
SbE
S
SbW
SSW
SWbS
SW
SWbW
WSW
WbS
W
WbN
WNW
NWbW
NW
NWbN
NNW
NbW
End Enum
Code:
Public Class Helper
Public Function DegreesToCardinalMark(ByVal degrees As Double, ByVal numCardinalPoints As Integer) As String
degrees = degrees Mod 360
Dim compassPoint As Integer = CInt(Math.Truncate((degrees / 360) * numCardinalPoints + 0.5) * 32 / numCardinalPoints) Mod 32
Return CardinalPoints.GetName(GetType(CardinalPoints), compassPoint).ToString()
End Function
End Class
Code:
Public Class Form1
Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim a As New Helper
MessageBox.Show(a.DegreesToCardinalMark(750.0, 8))
End Sub
End Class