Private Sub DrawLine()
        Dim width As Double = 2000
        Dim height As Double = width / 2
        Dim lst() As Double = GetRandomValueList(CInt(width))
        Dim p As New Pen(Brushes.DarkBlue, 1)
 
        Dim d As Date = Now
 
        Dim dGroup As New DrawingGroup
        Using dc As DrawingContext = dGroup.Open
            dc.DrawRectangle(Brushes.Transparent, New Pen(Brushes.Black, 2), _
              New Rect(0, 0, width, height))
            For i As Integer = 0 To lst.Count - 2
                dc.DrawLine(p, New Point(i, lst(i) * height), New Point(i + 1, _
                  lst(i + 1) * height))
            Next
        End Using
        Image1.Source = New DrawingImage(dGroup)
 
        Debug.WriteLine((Now - d).TotalMilliseconds)
    End Sub
 
 
 
    Private Function GetRandomValueList(ByVal maximum As Integer) As Double()
        Dim lst As New List(Of Double)
        For i As Integer = 0 To maximum
            Randomize()
            lst.Add(Rnd())
        Next
        Return lst.ToArray
    End Function