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.

Tutorials

Properties

bool

auto_accept_quit

true

Node

current_scene

bool

debug_collisions_hint

false

bool

debug_navigation_hint

false

Node

edited_scene_root

bool

multiplayer_poll

true

bool

paused

false

bool

quit_on_go_back

true

Window

root

Methods

void

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

void

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

MultiplayerAPI

get_multiplayer ( NodePath for_path=NodePath("") ) 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_group ( StringName group, String property, Variant value )

void

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

void

set_multiplayer ( MultiplayerAPI multiplayer, NodePath root_path=NodePath("") )

Signals

  • 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_DEFERRED = 2 --- Call a group with a one-frame delay (idle frame, not physics).

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

Property Descriptions

  • bool auto_accept_quit

Default

true

Setter

set_auto_accept_quit(value)

Getter

is_auto_accept_quit()

If true, the application automatically accepts quitting.

For mobile platforms, see quit_on_go_back.


  • 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.


  • 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:


  • bool quit_on_go_back

Default

true

Setter

set_quit_on_go_back(value)

Getter

is_quit_on_go_back()

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

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


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.

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

Note: call_group will call methods immediately on all members at once, which can cause stuttering if an expensive method is called on lots of members. To wait for one frame after call_group was called, use call_group_flags with the GROUP_CALL_DEFERRED 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.

# Call the method in a deferred manner and in reverse order.
get_tree().call_group_flags(SceneTree.GROUP_CALL_DEFERRED | SceneTree.GROUP_CALL_REVERSE)

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

Note: Group call flags are used to control the method calling behavior. By default, methods will be called immediately in a way similar to call_group. However, if the GROUP_CALL_DEFERRED flag is present in the flags argument, methods will be called with a one-frame delay in a way similar to Object.set_deferred.


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.


Returns the first node in the specified group, or null if the group is empty or does not exist.


  • int get_frame ( ) const

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


Return the MultiplayerAPI configured for the given path, or the default one if for_path is empty.


  • 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.

Note: notify_group will immediately notify all members at once, which can cause stuttering if an expensive method is called as a result of sending the notification lots of members. To wait for one frame, use notify_group_flags with the GROUP_CALL_DEFERRED flag.


  • 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.

Note: Group call flags are used to control the notification sending behavior. By default, notifications will be sent immediately in a way similar to notify_group. However, if the GROUP_CALL_DEFERRED flag is present in the flags argument, notifications will be sent with a one-frame delay in a way similar to using Object.call_deferred("notification", ...).


  • 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.


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

Note: set_group will set the property immediately on all members at once, which can cause stuttering if a property with an expensive setter is set on lots of members. To wait for one frame, use set_group_flags with the GROUP_CALL_DEFERRED flag.


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

Note: Group call flags are used to control the property setting behavior. By default, properties will be set immediately in a way similar to set_group. However, if the GROUP_CALL_DEFERRED flag is present in the flags argument, properties will be set with a one-frame delay in a way similar to Object.call_deferred.


Sets a custom MultiplayerAPI with the given root_path (controlling also the relative subpaths), or override the default one if root_path is empty.