Найти центр PictureBox на форме

Imports System.IO
Imports System.Windows.Forms
Imports System.Security.Permissions
Public Class Form1
    Public timeLeft As Integer = 30
    Dim iRand As Integer
    Dim x1, y1 As Single
    Dim b2 As SolidBrush
    Public Function LoadImageFromFile(path As String) As Image
        Try
            Using fs As New FileStream(path, FileMode.Open, FileAccess.Read)
                Dim img = Image.FromStream(fs)
                Return img
            End Using
        Catch ex As Exception
            Dim unused = MsgBox(Prompt:=ex.Message)
        End Try
        '# Disable Warning BC42105
        ' #region Disable Warning BC42105
    End Function
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        PictureBox1.BackgroundImage = LoadImageFromFile(Application.StartupPath & "\" & "Бункер.jpg")
        PictureBox1.BackgroundImageLayout = ImageLayout.Stretch
        CountIRand()
        PictureBox2CreateGraphics(iRand)
        'KeyPreview = True
        'Me.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedSingle
        'Me.MaximizeBox = False
 
        PictureBox1.Anchor = AnchorStyles.Bottom Or AnchorStyles.Left Or AnchorStyles.Right Or AnchorStyles.Top
    End Sub
    Private Sub PictureBox1_Click(sender As Object, e As EventArgs) Handles PictureBox1.Click
        CountIRand()
        PictureBox1CreateGraphics(iRand)
        CountIRand()
        PictureBox2CreateGraphics(iRand)
    End Sub
    Private Sub PictureBox2CreateGraphics(iRand)
        Dim g As Graphics = PictureBox2.CreateGraphics
        If iRand = 1 Then
            b2 = New SolidBrush(Color.Red)
        Else
            b2 = New SolidBrush(Color.LimeGreen)
        End If
        g.SmoothingMode = Drawing2D.SmoothingMode.HighQuality 'качество отрисовки
        g.PageUnit = GraphicsUnit.Millimeter     'единица измерения - миллиметр
        g.FillEllipse(b2, x1, 0, 18, 18)
    End Sub
    Private Sub PictureBox1CreateGraphics(iRand)
        Dim g As Graphics = PictureBox1.CreateGraphics
        Dim b1 As SolidBrush
        If iRand = 1 Then
            b1 = New SolidBrush(Color.Red)
        Else
            b1 = New SolidBrush(Color.LimeGreen)
        End If
 
        g.SmoothingMode = Drawing2D.SmoothingMode.HighQuality 'качество отрисовки
        g.PageUnit = GraphicsUnit.Millimeter     'единица измерения - миллиметр
        'x1 = PictureBox1.Width / 2 - 358
        'y1 = PictureBox1.Height - 270
 
        'x1 = PictureBox1.Width / 8.15
        'y1 = PictureBox1.Height / 4
 
        x1 = PictureBox1.Width / 7.6 - 9
        y1 = PictureBox1.Height / 3.5 - 18
 
 
        g.FillEllipse(b1, x1, y1, 18, 18)
    End Sub
    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Label2.Text = "0"
        Label4.Text = "0"
        Label6.Text = "0"
        Label7.Text = "0"
        Label10.Text = "0"
        Label11.Text = "0"
        Label13.Text = "0"
        Label15.Text = "0"
    End Sub
    Private Sub CountIRand()
        Dim oRand = New Random()
        oRand = New Random(DateTime.Now.Millisecond)
        iRand = oRand.Next(1, 3)
    End Sub
    Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
        If PictureBox2.Visible = False Then
            If b2.Color = Color.Red Then
                PictureBox2CreateGraphics(1)
            Else
                PictureBox2CreateGraphics(2)
            End If
            PictureBox2.Visible = True
            Button2.Text = "Скрыть"
        Else
            PictureBox2.Visible = False
            Button2.Text = "Показать"
        End If
    End Sub
    Private Sub Button1_PreviewKeyDown(sender As Object, e As PreviewKeyDownEventArgs) Handles Button1.PreviewKeyDown
        e.IsInputKey = True
    End Sub
    Private Sub Form1_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown
        If e.KeyCode = Keys.Left Then
            If b2.Color = Color.Red Then
                Label2.Text = Label2.Text + 1
                Label6.Text = Label6.Text + 1
            Else
                Label2.Text = Label2.Text + 1
                Label10.Text = Label10.Text + 1
                Label13.Text = Label6.Text / Label2.Text * 100
            End If
        End If
 
        If e.KeyCode = Keys.Right Then
            If b2.Color = Color.LimeGreen Then
                Label4.Text = Label4.Text + 1
                Label7.Text = Label7.Text + 1
            Else
                Label4.Text = Label4.Text + 1
                Label11.Text = Label11.Text + 1
                Label15.Text = Label7.Text / Label4.Text * 100
            End If
        End If
        Label18.Text = Label18.Text + 1
        CountIRand()
        PictureBox2CreateGraphics(iRand)
        'CountIRand()
        'PictureBox1CreateGraphics(iRand)
    End Sub
    'Private Sub Form1_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Resize
    '    Dim x2, x3, x4, y2, y3 As Integer
    '    x1 = PictureBox1.Width / 2 - 358
    '    y1 = PictureBox1.Height - 270
    '    x1 = PictureBox1.Width / 2 - 358
    '    y1 = PictureBox1.Height - 270
    '    x2 = (PictureBox1.Left) + PictureBox1.Width / 2
 
    '    y2 = (PictureBox1.Top) + PictureBox1.Height / 2
    '    x3 = Me.ClientSize.Width / 2
    '    x4 = Me.ClientSize.Width / 2 - PictureBox1.Width / 2
    '    y3 = Me.ClientSize.Height / 2 - PictureBox1.Height / 2 + 100
    '    PictureBox1.Location = New Point((Me.ClientSize.Width / 2 - PictureBox1.Width / 2), (Me.ClientSize.Height / 2 - PictureBox1.Height / 2))
    'End Sub
 
    Private Sub PictureBox2_Paint(sender As Object, e As PaintEventArgs) Handles PictureBox2.Paint
 
    End Sub
End Class