Public Class Form1

    Dim jumpLimit As Short = 100
    Dim charGround As Short = 200

    Private charSize As New Size(30, 30)
    Private charPos As New Point(200, charGround)
    Private character As Rectangle

    Private WithEvents tmrRefresh As New Timer
    Private GameRefresh As Short = 60   ' ms.

    Private counterTimer As Short = 0

    Private _jumpAction As Byte = 0
    Public Property JumpAction() As Byte
        Get
            Return _jumpAction
        End Get
        Set(ByVal value As Byte)
            _jumpAction = value
            Select Case value
                Case Is = 0     ' De pie.
                    ' *****
                Case Is = 1     ' Ascendiendo.                   
                    Call JumpUp()
                Case Is = 2     ' Descendiendo.
                    Call JumpDown()
            End Select
        End Set
    End Property

    Public Sub New()
        ' Llamada necesaria para el diseñador.
        InitializeComponent()
        ' Agregue cualquier inicialización después de la llamada a InitializeComponent().
        Me.SetStyle(ControlStyles.UserPaint, True)
        Me.SetStyle(ControlStyles.AllPaintingInWmPaint, True)
        Me.SetStyle(ControlStyles.OptimizedDoubleBuffer, True)
        Me.DoubleBuffered = True
        tmrRefresh.Interval = GameRefresh
        tmrRefresh.Start()
    End Sub

    Private Sub Form1_KeyDown(sender As Object,
                              e As KeyEventArgs) Handles Me.KeyDown
        Select Case e.KeyCode
            Case Is = Keys.Left
                charPos.X -= 2
            Case Is = Keys.Right
                charPos.X += 2
            Case Is = Keys.Space
                JumpAction = 1
        End Select
    End Sub

    Private Sub JumpUp()
        If charPos.Y = jumpLimit Then JumpAction = 2 : Exit Sub
        If charPos.Y > jumpLimit And JumpAction = 1 Then
            charPos.Y -= 5
        End If
    End Sub

    Private Sub JumpDown()
        If charPos.Y = charGround Then JumpAction = 0 : Exit Sub
        charPos.Y += 5
    End Sub

    Private Sub tmrRefresh_Tick(sender As Object,
                                e As EventArgs) Handles tmrRefresh.Tick
        ' Contador de tiempo.
        If counterTimer < 99 Then
            counterTimer += 1 : Else : counterTimer = 0
        End If
        If JumpAction = 1 Then JumpUp()
        If JumpAction = 2 Then JumpDown()
        Me.Refresh()
    End Sub

    Private Sub draw(e As PaintEventArgs)
        character = New Rectangle(charPos, charSize)
        e.Graphics.FillRectangle(Brushes.Red, character)
    End Sub

    Protected Overrides Sub OnPaint(e As PaintEventArgs)
        MyBase.OnPaint(e)
        Call draw(e)
    End Sub




End Class