Node

Inherits: Object

Inherited By: Viewport, Timer, CanvasLayer, EventPlayer, SoundRoomParams, Spatial, AnimationPlayer, EditorPlugin, ResourcePreloader, AnimationTreePlayer, SamplePlayer, InstancePlaceholder, HTTPRequest, StreamPlayer, CanvasItem, Tween

Category: Core

Brief Description

Base class for all the scene elements.

Member Functions

void _enter_tree ( ) virtual
void _exit_tree ( ) virtual
void _fixed_process ( float delta ) virtual
void _input ( InputEvent event ) virtual
void _process ( float delta ) virtual
void _ready ( ) virtual
void _unhandled_input ( InputEvent event ) virtual
void _unhandled_key_input ( InputEvent key_event ) virtual
void add_child ( Node node, bool legible_unique_name=false )
void add_to_group ( String group, bool persistent=false )
bool can_process ( ) const
Node duplicate ( bool use_instancing=false, int flags=7 ) const
Node find_node ( String mask, bool recursive=true, bool owned=true ) const
Node get_child ( int idx ) const
int get_child_count ( ) const
Array get_children ( ) const
String get_filename ( ) const
float get_fixed_process_delta_time ( ) const
Array get_groups ( ) const
int get_index ( ) const
String get_name ( ) const
Node get_node ( NodePath path ) const
Array get_node_and_resource ( NodePath path )
Node get_owner ( ) const
Node get_parent ( ) const
NodePath get_path ( ) const
NodePath get_path_to ( Node node ) const
int get_pause_mode ( ) const
int get_position_in_parent ( ) const
float get_process_delta_time ( ) const
bool get_scene_instance_load_placeholder ( ) const
SceneTree get_tree ( ) const
Object get_viewport ( ) const
bool has_node ( NodePath path ) const
bool has_node_and_resource ( NodePath path ) const
bool is_a_parent_of ( Node node ) const
bool is_displayed_folded ( ) const
bool is_fixed_processing ( ) const
bool is_greater_than ( Node node ) const
bool is_in_group ( String group ) const
bool is_inside_tree ( ) const
bool is_processing ( ) const
bool is_processing_input ( ) const
bool is_processing_unhandled_input ( ) const
bool is_processing_unhandled_key_input ( ) const
void move_child ( Node child_node, int to_pos )
void print_stray_nodes ( )
void print_tree ( )
void propagate_notification ( int what )
void queue_free ( )
void raise ( )
void remove_and_skip ( )
void remove_child ( Node node )
void remove_from_group ( String group )
void replace_by ( Node node, bool keep_data=false )
void set_display_folded ( bool fold )
void set_filename ( String filename )
void set_fixed_process ( bool enable )
void set_name ( String name )
void set_owner ( Node owner )
void set_pause_mode ( int mode )
void set_process ( bool enable )
void set_process_input ( bool enable )
void set_process_unhandled_input ( bool enable )
void set_process_unhandled_key_input ( bool enable )
void set_scene_instance_load_placeholder ( bool load_placeholder )

Signals

  • enter_tree ( )
  • exit_tree ( )
  • renamed ( )

Numeric Constants

  • NOTIFICATION_ENTER_TREE = 10
  • NOTIFICATION_EXIT_TREE = 11
  • NOTIFICATION_MOVED_IN_PARENT = 12
  • NOTIFICATION_READY = 13
  • NOTIFICATION_FIXED_PROCESS = 16
  • NOTIFICATION_PROCESS = 17 — Notification received every frame when the process flag is set (see set_process).
  • NOTIFICATION_PARENTED = 18 — Notification received when a node is set as a child of another node. Note that this doesn’t mean that a node entered the Scene Tree.
  • NOTIFICATION_UNPARENTED = 19 — Notification received when a node is unparented (parent removed it from the list of children).
  • NOTIFICATION_PAUSED = 14
  • NOTIFICATION_UNPAUSED = 15
  • NOTIFICATION_INSTANCED = 20
  • NOTIFICATION_DRAG_BEGIN = 21
  • NOTIFICATION_DRAG_END = 22
  • PAUSE_MODE_INHERIT = 0
  • PAUSE_MODE_STOP = 1
  • PAUSE_MODE_PROCESS = 2
  • DUPLICATE_SIGNALS = 1
  • DUPLICATE_GROUPS = 2
  • DUPLICATE_SCRIPTS = 4

Description

Nodes are the base bricks with which Godot games are developed. They can be set as children of other nodes, resulting in a tree arrangement. A given node can contain any number of nodes as children (but there is only one scene tree root node) with the requirement that all siblings (direct children of a node) should have unique names.

Any tree of nodes is called a scene. Scenes can be saved to the disk and then instanced into other scenes. This allows for very high flexibility in the architecture and data model of the projects. Nodes can optionally be added to groups. This makes it easy to reach a number of nodes from the code (for example an “enemies” group) to perform grouped actions.

Scene tree: The SceneTree contains the active tree of nodes. When a node is added to the scene tree, it receives the NOTIFICATION_ENTER_TREE notification and its _enter_tree callback is triggered. Children nodes are always added after their parent node, i.e. the _enter_tree callback of a parent node will be triggered before its child’s.

Once all nodes have been added in the scene tree, they receive the NOTIFICATION_READY notification and their respective _ready callbacks are triggered. For groups of nodes, the _ready callback is called in reverse order, from the children up to the parent nodes.

It means that when adding a scene to the scene tree, the following order will be used for the callbacks: _enter_tree of the parent, _enter_tree of the children, _ready of the children and finally _ready of the parent (and that recursively for the whole scene).

Processing: Nodes can be set to the “process” state, so that they receive a callback on each frame requesting them to process (do something). Normal processing (callback _process, toggled with set_process) happens as fast as possible and is dependent on the frame rate, so the processing time delta is variable. Fixed processing (callback _fixed_process, toggled with set_fixed_process) happens a fixed amount of times per second (by default 60) and is useful to link itself to the physics.

Nodes can also process input events. When set, the _input function will be called for each input that the program receives. In many cases, this can be overkill (unless used for simple projects), and the _unhandled_input function might be preferred; it is called when the input event was not handled by anyone else (typically, GUI Control nodes), ensuring that the node only receives the events that were meant for it.

To keep track of the scene hierarchy (especially when instancing scenes into other scenes), an “owner” can be set for the node with set_owner. This keeps track of who instanced what. This is mostly useful when writing editors and tools, though.

Finally, when a node is freed with free or queue_free, it will also free all its children.

Member Function Description

  • void _enter_tree ( ) virtual

Called when the node enters the SceneTree (e.g. upon instancing, scene changing or after calling add_child in a script). If the node has children, its _enter_tree callback will be called first, and then that of the children.

Corresponds to the NOTIFICATION_ENTER_TREE notification in Object._notification.

  • void _exit_tree ( ) virtual

Called when the node leaves the SceneTree (e.g. upon freeing, scene changing or after calling remove_child in a script). If the node has children, its _exit_tree callback will be called last, after all its children have left the tree.

Corresponds to the NOTIFICATION_EXIT_TREE notification in Object._notification.

  • void _fixed_process ( float delta ) virtual

Called during the fixed processing step of the main loop. Fixed processing means that the frame rate is synced to the physics, i.e. the delta variable should be constant.

It is only called if fixed processing has been enabled with set_fixed_process.

Corresponds to the NOTIFICATION_FIXED_PROCESS notification in Object._notification.

Called for every input event.

It has to be enabled with set_process_input or the corresponding property in the inspector.

  • void _process ( float delta ) virtual

Called during the processing step of the main loop. Processing happens at every frame and as fast as possible, so the delta time since the previous frame is not constant.

It is only called if processing has been enabled with set_process.

Corresponds to the NOTIFICATION_PROCESS notification in Object._notification.

  • void _ready ( ) virtual

Called when the node is “ready”, i.e. when both the node and its children have entered the scene tree. If the node has children, their _ready callback gets triggered first, and the node will receive the ready notification only afterwards.

Corresponds to the NOTIFICATION_READY notification in Object._notification.

  • void _unhandled_input ( InputEvent event ) virtual

Called for every input event that has not already been handled by another node.

It has to be enabled with set_process_unhandled_input or the corresponding property in the inspector.

  • void _unhandled_key_input ( InputEvent key_event ) virtual

Called for every key input event that has not already been handled by another node.

It has to be enabled with set_process_unhandled_key_input or the corresponding property in the inspector.

  • void add_child ( Node node, bool legible_unique_name=false )

Add a child Node. Nodes can have as many children as they want, but every child must have a unique name. Children nodes are automatically deleted when the parent node is deleted, so deleting a whole scene is performed by deleting its topmost node.

The optional boolean argument enforces creating child nodes with human-readable names, based on the name of the node being instanced instead of its type only.

  • void add_to_group ( String group, bool persistent=false )

Add a node to a group. Groups are helpers to name and organize a subset of nodes, like for example “enemies” or “collectables”. A Node can be in any number of groups. Nodes can be assigned a group at any time, but will not be added to it until they are inside the scene tree (see is_inside_tree).

  • bool can_process ( ) const

Return true if the node can process, i.e. whether its pause mode allows processing while the scene tree is paused (see set_pause_mode). Always returns true if the scene tree is not paused, and false if the node is not in the tree. FIXME: Why FAIL_COND?

  • Node duplicate ( bool use_instancing=false, int flags=7 ) const

Duplicate the node, returning a new Node. If use_instancing is true, the duplicated node will be a new instance of the original PackedScene, if not it will be an independent node.

The flags are used to define what attributes (groups, signals, scripts) should be duplicated, as specified by the DUPLICATE_* constants. The default value is all of them.

Find a descendant of this node whose name matches mask as in String.match (i.e. case sensitive, but ‘*’ matches zero or more characters and ‘?’ matches any single character except ‘.’). Note that it does not match against the full path, just against individual node names.

Return a child node by its index (see get_child_count). This method is often used for iterating all children of a node.

  • int get_child_count ( ) const

Return the amount of child nodes.

  • Array get_children ( ) const

Return an array of references (Node) to the child nodes.

  • String get_filename ( ) const

Return a filename that may be contained by the node. When a scene is instanced from a file, it topmost node contains the filename from where it was loaded (see set_filename).

  • float get_fixed_process_delta_time ( ) const

Return the time elapsed since the last fixed frame (see _fixed_process). This is always the same in fixed processing unless the frames per second is changed in OS.

  • Array get_groups ( ) const

Return an array listing the groups that the node is part of.

  • int get_index ( ) const

Get the node index, i.e. its position among the siblings of its parent.

Return the name of the node. This name is unique among the siblings (other child nodes from the same parent).

Fetch a node. The NodePath must be valid (or else an error will be raised) and can be either the path to child node, a relative path (from the current node to another node), or an absolute path to a node.

Note: fetching absolute paths only works when the node is inside the scene tree (see is_inside_tree).

Example: Assume your current node is Character and the following tree:

/root
/root/Character
/root/Character/Sword
/root/Character/Backpack/Dagger
/root/MyGame
/root/Swamp/Alligator
/root/Swamp/Mosquito
/root/Swamp/Goblin

Possible paths are:

get_node("Sword")
get_node("Backpack/Dagger")
get_node("../Swamp/Alligator")
get_node("/root/MyGame")
  • Node get_owner ( ) const

Get the node owner (see set_owner).

  • Node get_parent ( ) const

Return the parent node of the current node, or an empty Node if the node lacks a parent.

Return the absolute path of the current node. This only works if the current node is inside the scene tree (see is_inside_tree).

Return the relative path from the current node to the specified node in “node” argument. Both nodes must be in the same scene, or else the function will fail.

  • int get_pause_mode ( ) const
  • int get_position_in_parent ( ) const
  • float get_process_delta_time ( ) const

Return the time elapsed (in seconds) since the last process callback. This is almost always different each time.

  • bool get_scene_instance_load_placeholder ( ) const
  • Object get_viewport ( ) const
  • bool is_a_parent_of ( Node node ) const

Return true if the “node” argument is a direct or indirect child of the current node, otherwise return false.

  • bool is_displayed_folded ( ) const
  • bool is_fixed_processing ( ) const

Return true if fixed processing is enabled (see set_fixed_process).

  • bool is_greater_than ( Node node ) const

Return true if “node” occurs later in the scene hierarchy than the current node, otherwise return false.

  • bool is_inside_tree ( ) const
  • bool is_processing ( ) const

Return whether processing is enabled in the current node (see set_process).

  • bool is_processing_input ( ) const

Return true if the node is processing input (see set_process_input).

  • bool is_processing_unhandled_input ( ) const

Return true if the node is processing unhandled input (see set_process_unhandled_input).

  • bool is_processing_unhandled_key_input ( ) const
  • void move_child ( Node child_node, int to_pos )

Move a child node to a different position (order) amongst the other children. Since calls, signals, etc are performed by tree order, changing the order of children nodes may be useful.

  • void print_stray_nodes ( )
  • void print_tree ( )

Print the scene to stdout. Used mainly for debugging purposes.

  • void propagate_notification ( int what )

Notify the current node and all its children recursively by calling notification() in all of them.

  • void queue_free ( )
  • void raise ( )

Move this node to the top of the array of nodes of the parent node. This is often useful on GUIs (Control), because their order of drawing fully depends on their order in the tree.

  • void remove_and_skip ( )

Remove a node and set all its children as children of the parent node (if exists). All even subscriptions that pass by the removed node will be unsubscribed.

  • void remove_child ( Node node )

Remove a child Node. Node is NOT deleted and will have to be deleted manually.

  • void remove_from_group ( String group )

Remove a node from a group.

  • void replace_by ( Node node, bool keep_data=false )

Replace a node in a scene by a given one. Subscriptions that pass through this node will be lost.

  • void set_display_folded ( bool fold )
  • void set_filename ( String filename )

A node can contain a filename. This filename should not be changed by the user, unless writing editors and tools. When a scene is instanced from a file, it topmost node contains the filename from where it was loaded.

  • void set_fixed_process ( bool enable )

Enables or disables node fixed framerate processing. When a node is being processed, it will receive a NOTIFICATION_PROCESS at a fixed (usually 60 fps, check OS to change that) interval (and the _fixed_process callback will be called if exists). It is common to check how much time was elapsed since the previous frame by calling get_fixed_process_delta_time.

  • void set_name ( String name )

Set the name of the Node. Name must be unique within parent, and setting an already existing name will cause for the node to be automatically renamed.

  • void set_owner ( Node owner )

Set the node owner. A node can have any other node as owner (as long as a valid parent, grandparent, etc ascending in the tree). When saving a node (using SceneSaver) all the nodes it owns will be saved with it. This allows to create complex SceneTrees, with instancing and subinstancing.

  • void set_pause_mode ( int mode )
  • void set_process ( bool enable )

Enables or disables node processing. When a node is being processed, it will receive a NOTIFICATION_PROCESS on every drawn frame (and the _process callback will be called if exists). It is common to check how much time was elapsed since the previous frame by calling get_process_delta_time.

  • void set_process_input ( bool enable )

Enable input processing for node. This is not required for GUI controls! It hooks up the node to receive all input (see _input).

  • void set_process_unhandled_input ( bool enable )

Enable unhandled input processing for node. This is not required for GUI controls! It hooks up the node to receive all input that was not previously handled before (usually by a Control). (see _unhandled_input).

  • void set_process_unhandled_key_input ( bool enable )
  • void set_scene_instance_load_placeholder ( bool load_placeholder )