Detects when the node is visible on screen. The VisibilityNotifier2D detects when it is visible on the screen. It also notifies when its bounding rectangle enters or exits the screen or a viewport. Returns the bounding rectangle of the VisibilityNotifier2D. If [code]true[/code] the bounding rectangle is on the screen. Set the visibility bounding rectangle of the VisibilityNotifier2D. The VisibilityNotifier2D's bounding rectangle. Emitted when the VisibilityNotifier2D enters the screen. Emitted when the VisibilityNotifier2D exits the screen. Emitted when the VisibilityNotifier2D enters a [Viewport]'s view. Emitted when the VisibilityNotifier2D exits a [Viewport]'s view.