Detects approximately when the node is visible on screen. The VisibilityNotifier detects when it is visible on the screen. It also notifies when its bounding rectangle enters or exits the screen or a [Camera]'s view. If you want nodes to be disabled automatically when they exit the screen, use [VisibilityEnabler] instead. [b]Note:[/b] VisibilityNotifier uses an approximate heuristic for performance reasons. It doesn't take walls and other occlusion into account (unless you are using [Portal]s). The heuristic is an implementation detail and may change in future versions. If you need precise visibility checking, use another method such as adding an [Area] node as a child of a [Camera] node and/or [method Vector3.dot]. If [code]true[/code], the bounding box is on the screen. [b]Note:[/b] It takes one frame for the node's visibility to be assessed once added to the scene tree, so this method will return [code]false[/code] right after it is instantiated, even if it will be on screen in the draw pass. The VisibilityNotifier's bounding box. In addition to checking whether a node is on screen or within a [Camera]'s view, VisibilityNotifier can also optionally check whether a node is within a specified maximum distance when using a [Camera] with perspective projection. This is useful for throttling the performance requirements of nodes that are far away. [b]Note:[/b] This feature will be disabled if set to 0.0. Emitted when the VisibilityNotifier enters a [Camera]'s view. Emitted when the VisibilityNotifier exits a [Camera]'s view. Emitted when the VisibilityNotifier enters the screen. Emitted when the VisibilityNotifier exits the screen.