clsShape e clsShapeOval
Public MustInherit Class clsShape
    Private mRectangle As Rectangle
    Private mSelected As Boolean = False
    Private mShapeContainer As clsShapeContainer
    Private Shared ZoomFactor As Integer = 5

    Public MustOverride Sub Draw(ByRef g As Graphics)


    Public Sub New(ByVal X As Integer, ByVal Y As Integer, ByVal Width As Integer, ByVal Height As Integer, ByRef Parent As clsShapeContainer)
        mRectangle = New Rectangle(X, Y, Width, Height)
        mShapeContainer = Parent
    End Sub

    Public Property Selected() As Boolean
        Get
            Return mSelected
        End Get
        Set(ByVal value As Boolean)
            mSelected = value           
        End Set
    End Property

    Public Property Rectangle() As Rectangle
        Get
            Return mRectangle
        End Get
        Set(ByVal value As Rectangle)
            mRectangle = value
        End Set
    End Property

    Public ReadOnly Property InvalidationRect() As Rectangle
        Get
            Return New Rectangle(mRectangle.X, mRectangle.Y, mRectangle.Width + 1, mRectangle.Height + 1)
        End Get
    End Property

    Public ReadOnly Property Parent() As clsShapeContainer
        Get
            Return mShapeContainer
        End Get
    End Property

    Public Sub ZoomIn()
        Me.mRectangle.Inflate(ZoomFactor, ZoomFactor)
    End Sub

    Public Sub ZoomOut()
        If Me.mRectangle.Width > (ZoomFactor * 2) AndAlso Me.mRectangle.Height > (ZoomFactor * 2) Then
            Me.mRectangle.Inflate(ZoomFactor * -1, ZoomFactor * -1)
        End If
    End Sub

    Public Sub Move(ByVal NewPt As Point)
        Dim Region As New Region(Me.InvalidationRect)
        Me.mRectangle.Location = NewPt
        Region.Union(Me.InvalidationRect)

        Parent.Invalidate(Region)
    End Sub
End Class



Public Class clsShapeOval
    Inherits clsShape
    Private Shared mPen As New Pen(Color.Black)
    Private Shared mPenSelected As New Pen(Color.Red)


    Private mWidth As Integer = 30
    Private mHeigth As Integer = 30


    Public Sub New(ByVal X As Integer, ByVal Y As Integer, ByRef Parent As clsShapeContainer)

        MyBase.New(X, Y, 30, 30, Parent)

    End Sub

    Public Overrides Sub Draw(ByRef g As System.Drawing.Graphics)
        Using mGradiendBrush As New System.Drawing.Drawing2D.LinearGradientBrush(New Rectangle(Rectangle.X, Rectangle.Y, Rectangle.Width, Rectangle.Height), Color.Yellow, Color.Orange, Drawing2D.LinearGradientMode.Vertical)

            If Me.Selected Then
                g.DrawEllipse(mPenSelected, Rectangle)
            Else
                g.DrawEllipse(mPen, Rectangle)
            End If
            g.FillEllipse(mGradiendBrush, Rectangle)
        End Using


    End Sub
End Class