Нарисовать правильный 8-ми угольник

 Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim ris As Graphics
        ris = Me.PictureBox1.CreateGraphics
        Dim a, b, c, o As Point
        Dim alf, bet, gam As Double
        Dim i, l As Integer
        o.X = 150
        o.Y = 150
        l = 150
        For i = 0 To 100
            alf = 5 * i * Math.PI / 180
            bet = 90 * Math.PI / 180
            gam = 30 * Math.PI / 180
            a.X = o.X + l * Math.Cos(alf)
            a.Y = o.Y - l * Math.Sin(alf)
            b.X = a.X - 30 * Math.Cos(alf - bet)
            b.Y = a.Y + 30 * Math.Sin(alf - bet)
            c.X = a.X - 30 * Math.Cos(alf + gam)
            c.Y = a.Y + 30 * Math.Sin(alf + gam)
            ris.DrawLine(Pens.Black, o, a)
            ris.DrawLine(Pens.Black, a, b)
            ris.DrawLine(Pens.Black, b, o)
            Threading.Thread.Sleep(50)
            ris.Clear(Color.White)
        Next i
 
 
 
    End Sub
End Class

 Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        Dim ris As Graphics
        ris = Me.PictureBox1.CreateGraphics
        Dim P1 As New Pen(Color.Red, 3)
        ' Задаем координаты полигона
        Dim Pol1() As Point = {New Point(20, 100), New Point(50, 50), New Point(100, 50), New Point(120, 100), New Point(120, 150), New Point(100, 200), New Point(50, 200), New Point(20, 100)}
        ris.DrawPolygon(P1, Pol1)
    End Sub

New Point(20, 100)

    Private Sub Form1_Paint(ByVal sender As Object, ByVal e As PaintEventArgs) Handles Me.Paint
        ' DrawRegularPolygon(Координаты центра окружности, Количество вершин, Радиус, e.Graphics)
        DrawRegularPolygon(New PointF(100, 100), 8, 100, e.Graphics)
    End Sub
    ' center Координаты центра окружности, vertexes Количество вершин, radius Радиус
    Private Sub DrawRegularPolygon(ByVal center As PointF, ByVal vertexes As Integer, ByVal radius As Single, ByVal graphics As Graphics)
        Dim angle = Math.PI * 2 / vertexes
        Dim points = Enumerable.Range(0, vertexes).[Select](Function(i) PointF.Add(center, New SizeF(CSng(Math.Sin(i * angle)) * radius, CSng(Math.Cos(i * angle)) * radius)))
        graphics.DrawPolygon(Pens.Black, points.ToArray())
        ' рисует описанный круг
        'graphics.DrawEllipse(Pens.Aqua, New RectangleF(PointF.Subtract(center, New SizeF(radius, radius)), New SizeF(radius * 2, radius * 2)))
    End Sub

  Threading.Thread.Sleep(50)

' center Координаты центра окружности, vertexes Количество вершин, radius Радиус
    Private Sub DrawRegularPolygon(ByVal center As PointF, ByVal vertexes As Integer, ByVal radius As Single, ByVal graphics As Graphics)
        Dim angle = Math.PI * 2 / vertexes
        Dim points = Enumerable.Range(0, vertexes).[Select](Function(i) PointF.Add(center, New SizeF(CSng(Math.Sin(i * angle)) * radius, CSng(Math.Cos(i * angle)) * radius))).ToList
        points.Add(New PointF(points(0).X, points(0).Y))
        For i = 0 To vertexes - 1
            graphics.DrawLine(Pens.Black, points(i), points(i + 1))
            Threading.Thread.Sleep(50)
        Next
 
        'graphics.DrawPolygon(Pens.Black, points.ToArray())
        ' рисует описанный круг
        'graphics.DrawEllipse(Pens.Aqua, New RectangleF(PointF.Subtract(center, New SizeF(radius, radius)), New SizeF(radius * 2, radius * 2)))
    End Sub

Public Class Form1
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Dim O, A, B, C As Point
Dim Gr As Graphics
Dim L, H, i As Integer
Dim alf, bet, gam As Double
L = 100
H = 30
Gr = картинка.CreateGraphics
O.X = 200
O.Y = 200
For i = 0 To 100
alf = 5 * i * Math.PI / 180
bet = 90 * Math.PI / 180
gam = 30 * Math.PI / 180
A.X = O.X + L * Math.Cos(alf)
A.Y = O.Y - L * Math.Sin(alf)
Gr.DrawLine(Pens.Black, O, A)
B.X = A.X - 30 * Math.Cos(alf - bet)
B.Y = A.Y + 30 * Math.Sin(alf - bet)
C.X = A.X - 30 * Math.Cos(alf - gam)
C.Y = A.Y + 30 * Math.Sin(alf - gam)
Gr.DrawLine(Pens.Black, A, B)
Gr.DrawLine(Pens.Black, A, C)
Gr.DrawLine(Pens.Black, B, C)
Threading.Thread.Sleep(50)
Gr.Clear(Color.White)
Next
End Sub
End Class

Imports System.Drawing.Drawing2D
 
Public Class Form1
 
    Public Sub New()
 
        ' This call is required by the designer.
        InitializeComponent()
 
        ' Add any initialization after the InitializeComponent() call.
        points = GetPolygon(8, 200)
        m.Rotate(10.0F)
        AddHandler t.Tick, AddressOf timer_Tick
        SetStyle(ControlStyles.ResizeRedraw, True)
    End Sub
    ''' <summary>
    ''' Правильный многоугольник по заданному числу сторон и радиусу описанной окружности
    ''' </summary>
    ''' <param name="n">Количество сторон</param>
    ''' <param name="r">Радиус описанной окружности</param>
    ''' <exception cref="ArgumentException">Возникает, если указанное число сторон меньше 3</exception>
    Private Function GetPolygon(ByVal n As Integer, ByVal r As Single) As PointF()
        If n < 3 Then
            Throw New ArgumentException("Число сторон должно быть больше 3.")
        End If
        If r < 0 Then
            Throw New ArgumentException("Радиус должен быть положительным числом")
        End If
        Dim result = New PointF(n) {}
        Dim angle = 2 * Math.PI / n
        For i = 0 To n
            Dim x = r * Math.Cos(i * angle)
            Dim y = r * Math.Sin(i * angle)
            result(i) = New PointF(x, y)
        Next
        Return result
    End Function
    'Вершины многоугольника
    Private points As PointF()
    'Таймер
    Private ReadOnly t As New Timer With {.Interval = 200}
    'Матрица поворота
    Private ReadOnly m As New Matrix
 
    Private Sub timer_Tick(sender As Object, e As EventArgs)
        'По таймеру поворачиваем вершины многоугольника матрицей аффинных преобразований
        m.TransformPoints(points)
        'Обновляем форму
        Invalidate()
    End Sub
 
    'Запуск/останов таймера по двойному клику
    Protected Overrides Sub OnMouseDoubleClick(e As MouseEventArgs)
        MyBase.OnMouseDoubleClick(e)
        t.Enabled = Not t.Enabled
    End Sub
 
    'Прорисовка многоугольника по центру формы
    Protected Overrides Sub OnPaint(e As PaintEventArgs)
        MyBase.OnPaint(e)
        Dim dx = ClientSize.Width / 2.0F
        Dim dy = ClientSize.Height / 2.0F
        e.Graphics.TranslateTransform(dx, dy)
        e.Graphics.DrawPolygon(Pens.Blue, points)
    End Sub
End Class