SceneTree

Inherits: MainLoop < Object

Manages the game loop via a hierarchy of nodes.

Description

As one of the most important classes, the SceneTree manages the hierarchy of nodes in a scene as well as scenes themselves. Nodes can be added, retrieved and removed. The whole scene tree (and thus the current scene) can be paused. Scenes can be loaded, switched and reloaded.

You can also use the SceneTree to organize your nodes into groups: every node can be assigned as many groups as you want to create, e.g. an "enemy" group. You can then iterate these groups or even call methods and set properties on all the group's members at once.

SceneTree is the default MainLoop implementation used by scenes, and is thus in charge of the game loop.

Methods

Variant

call_group ( StringName group, StringName method, ... ) vararg

Variant

call_group_flags ( int flags, StringName group, StringName method, ... ) vararg

Error

change_scene ( String path )

Error

change_scene_to ( PackedScene packed_scene )

SceneTreeTimer

create_timer ( float time_sec, bool process_always=true )

Tween

create_tween ( )

Node

get_first_node_in_group ( StringName group )

int

get_frame ( ) const

int

get_node_count ( ) const

Array

get_nodes_in_group ( StringName group )

Array

get_processed_tweens ( )

bool

has_group ( StringName name ) const

void

notify_group ( StringName group, int notification )

void

notify_group_flags ( int call_flags, StringName group, int notification )

void

queue_delete ( Object obj )

void

quit ( int exit_code=0 )

Error

reload_current_scene ( )

void

set_auto_accept_quit ( bool enabled )

void

set_group ( StringName group, String property, Variant value )

void

set_group_flags ( int call_flags, StringName group, String property, Variant value )

void

set_quit_on_go_back ( bool enabled )

Signals

Emitted when files are dragged from the OS file manager and dropped in the game window. The arguments are a list of file paths and the identifier of the screen where the drag originated.


  • node_added ( Node node )

Emitted whenever a node is added to the SceneTree.


  • node_configuration_warning_changed ( Node node )

Emitted when a node's configuration changed. Only emitted in tool mode.


  • node_removed ( Node node )

Emitted whenever a node is removed from the SceneTree.


  • node_renamed ( Node node )

Emitted whenever a node is renamed.


  • physics_frame ( )

Emitted immediately before Node._physics_process is called on every node in the SceneTree.


  • process_frame ( )

Emitted immediately before Node._process is called on every node in the SceneTree.


  • tree_changed ( )

Emitted whenever the SceneTree hierarchy changed (children being moved or renamed, etc.).


  • tree_process_mode_changed ( )

This signal is only emitted in the editor, it allows the editor to update the visibility of disabled nodes. Emitted whenever any node's Node.process_mode is changed.

Enumerations

enum GroupCallFlags:

  • GROUP_CALL_DEFAULT = 0 --- Call a group with no flags (default).

  • GROUP_CALL_REVERSE = 1 --- Call a group in reverse scene order.

  • GROUP_CALL_REALTIME = 2 --- Call a group immediately (calls are normally made on idle).

  • GROUP_CALL_UNIQUE = 4 --- Call a group only once even if the call is executed many times.

Property Descriptions

  • Node current_scene

Setter

set_current_scene(value)

Getter

get_current_scene()

The current scene.


  • bool debug_collisions_hint

Default

false

Setter

set_debug_collisions_hint(value)

Getter

is_debugging_collisions_hint()

If true, collision shapes will be visible when running the game from the editor for debugging purposes.


  • bool debug_navigation_hint

Default

false

Setter

set_debug_navigation_hint(value)

Getter

is_debugging_navigation_hint()

If true, navigation polygons will be visible when running the game from the editor for debugging purposes.


  • Node edited_scene_root

Setter

set_edited_scene_root(value)

Getter

get_edited_scene_root()

The root of the edited scene.


Setter

set_multiplayer(value)

Getter

get_multiplayer()

The default MultiplayerAPI instance for this SceneTree.


  • bool multiplayer_poll

Default

true

Setter

set_multiplayer_poll_enabled(value)

Getter

is_multiplayer_poll_enabled()

If true (default value), enables automatic polling of the MultiplayerAPI for this SceneTree during process_frame.

If false, you need to manually call MultiplayerAPI.poll to process network packets and deliver RPCs. This allows running RPCs in a different loop (e.g. physics, thread, specific time step) and for manual Mutex protection when accessing the MultiplayerAPI from threads.


Default

false

Setter

set_pause(value)

Getter

is_paused()

If true, the SceneTree is paused. Doing so will have the following behavior:


Getter

get_root()

The SceneTree's root Window.

Method Descriptions

Calls method on each member of the given group. You can pass arguments to method by specifying them at the end of the method call. This method is equivalent of calling call_group_flags with GROUP_CALL_DEFAULT flag.

Note: Due to design limitations, call_group will fail silently if one of the arguments is null.

Note: call_group will always call methods with an one-frame delay, in a way similar to Object.call_deferred. To call methods immediately, use call_group_flags with the GROUP_CALL_REALTIME flag.


Calls method on each member of the given group, respecting the given GroupCallFlags. You can pass arguments to method by specifying them at the end of the method call.

Note: Due to design limitations, call_group_flags will fail silently if one of the arguments is null.

# Call the method immediately and in reverse order.
get_tree().call_group_flags(SceneTree.GROUP_CALL_REALTIME | SceneTree.GROUP_CALL_REVERSE, "bases", "destroy")

Changes the running scene to the one at the given path, after loading it into a PackedScene and creating a new instance.

Returns @GlobalScope.OK on success, @GlobalScope.ERR_CANT_OPEN if the path cannot be loaded into a PackedScene, or @GlobalScope.ERR_CANT_CREATE if that scene cannot be instantiated.

Note: The scene change is deferred, which means that the new scene node is added on the next idle frame. You won't be able to access it immediately after the change_scene call.


Changes the running scene to a new instance of the given PackedScene.

Returns @GlobalScope.OK on success or @GlobalScope.ERR_CANT_CREATE if the scene cannot be instantiated.

Note: The scene change is deferred, which means that the new scene node is added on the next idle frame. You won't be able to access it immediately after the change_scene_to call.


Returns a SceneTreeTimer which will SceneTreeTimer.timeout after the given time in seconds elapsed in this SceneTree. If process_always is set to false, pausing the SceneTree will also pause the timer.

Commonly used to create a one-shot delay timer as in the following example:

func some_function():
    print("start")
    await get_tree().create_timer(1.0).timeout
    print("end")

The timer will be automatically freed after its time elapses.


Creates and returns a new Tween.



  • int get_frame ( ) const

Returns the current frame number, i.e. the total frame count since the application started.


  • int get_node_count ( ) const

Returns the number of nodes in this SceneTree.


Returns a list of all nodes assigned to the given group.


  • Array get_processed_tweens ( )

Returns an array of currently existing Tweens in the SceneTree (both running and paused).


Returns true if the given group exists.


Sends the given notification to all members of the group.


  • void notify_group_flags ( int call_flags, StringName group, int notification )

Sends the given notification to all members of the group, respecting the given GroupCallFlags.


  • void queue_delete ( Object obj )

Queues the given object for deletion, delaying the call to Object.free to after the current frame.


  • void quit ( int exit_code=0 )

Quits the application at the end of the current iteration. Argument exit_code can optionally be given (defaulting to 0) to customize the exit status code.

By convention, an exit code of 0 indicates success whereas a non-zero exit code indicates an error.

For portability reasons, the exit code should be set between 0 and 125 (inclusive).

Note: On iOS this method doesn't work. Instead, as recommended by the iOS Human Interface Guidelines, the user is expected to close apps via the Home button.


  • Error reload_current_scene ( )

Reloads the currently active scene.

Returns @GlobalScope.OK on success, @GlobalScope.ERR_UNCONFIGURED if no current_scene was defined yet, @GlobalScope.ERR_CANT_OPEN if current_scene cannot be loaded into a PackedScene, or @GlobalScope.ERR_CANT_CREATE if the scene cannot be instantiated.


  • void set_auto_accept_quit ( bool enabled )

If true, the application automatically accepts quitting. Enabled by default.

For mobile platforms, see set_quit_on_go_back.


Sets the given property to value on all members of the given group.


Sets the given property to value on all members of the given group, respecting the given GroupCallFlags.


  • void set_quit_on_go_back ( bool enabled )

If true, the application quits automatically on going back (e.g. on Android). Enabled by default.

To handle 'Go Back' button when this option is disabled, use DisplayServer.WINDOW_EVENT_GO_BACK_REQUEST.