What is wrong in this code

[anhdung]

I used code to divide a line into equal distant and resulted in picture as

http://img230.imageshack.us/my.php?image=dasdae1.gif

Private Sub Form_Load()
    Dim X1 As Long, Y1 As Long
    Dim X2 As Long, Y2 As Long
        
    Me.AutoRedraw = True
    Me.ScaleMode = vbPixels
    
    X1 = 20: Y1 = 50
    X2 = 300: Y2 = 400
   
    Me.Line (X1, Y1)-(X2, Y2)

    Call divideline(X1, Y1, X2, Y2, 50)

End Sub


Private Sub divideline(X1 As Long, Y1 As Long, X2 As Long, Y2 As Long, segments As Long)
Dim i As Long
Dim dy, Y As Single
Dim dx, X As Single
  dx = (X2 - X1) \ segments
  dy = (Y2 - Y1) \ segments
  For i = 0 To segments
    Circle (X1 + dx * i, Y1 + dy * i), 1 'or whatever
    X = X1 + dx * i
    Y = Y1 + dy * i
    List1.AddItem "X = " & X & vbTab & "Y = " & Y
  Next i
  
End Sub