NoCollisionMouse event occurs when the user presses on the GameWindow and no
sprite was pressed.
X and Y properties hold the mouse position.
Example:
Sub gw_NoCollisionMouse
'This event occurs when the user presses on the GameWindow and don't hit
any sprite.
form1.Text = "missed " & gw.X
& " " & gw.Y
panel1.Visible = false
End Sub