Шар по траектории! - VB

Option Explicit
Dim dx As Single, dy As Single, x As Single, y As Single
Private Sub Command1_Click()
    Do
         P1.Cls
         P1.Circle (x, y), 1, vbBlue
         DoEvents
         y = y + dy
         x = x + dx
         If x < -9 Or x > 9 Then dx = -dx
         If y < -9 Or y > 9 Then dy = -dy
    Loop
End Sub
 
Private Sub Form_Load()
    P1.ScaleMode = 3
    P1.FillColor = vbBlue
    P1.Scale (-10, 10)-(10, -10)
    x = 0
    y = 9
    dx = -0.01
    dy = -0.01
    P1.FillStyle = 0
    P1.AutoRedraw = True
End Sub
 
Private Sub Form_QueryUnload(Cancel As Integer, UnloadMode As Integer)
    End
End Sub