Manages the SceneTree selection in the editor. This object manages the SceneTree selection in the editor. [b]Note:[/b] This class shouldn't be instantiated directly. Instead, access the singleton using [method EditorInterface.get_selection]. Adds a node to the selection. [b]Note:[/b] The newly selected node will not be automatically edited in the inspector. If you want to edit a node, use [method EditorInterface.edit_node]. Clear the selection. Returns the list of selected nodes. Returns the list of selected nodes, optimized for transform operations (i.e. moving them, rotating, etc.). This list can be used to avoid situations where a node is selected and is also a child/grandchild. Removes a node from the selection. Emitted when the selection changes.