GDScript exports¶

Introduction to exports¶

In Godot, class members can be exported. This means their value gets saved along with the resource (such as the scene) they're attached to. They will also be available for editing in the property editor. Exporting is done by using the @export annotation:

extends Button

@export var number = 5 # Value will be saved and visible in the property editor.

An exported variable must be initialized to a constant expression or have a type specifier in the variable. Some of the export annotations have a specific type and don't need the variable to be typed (see the Examples section below).

One of the fundamental benefits of exporting member variables is to have them visible and editable in the editor. This way, artists and game designers can modify values that later influence how the program runs. For this, a special export syntax is provided.

Exporting can only be done with built-in types or objects derived from the Resource class.

Note

Exporting properties can also be done in other languages such as C#. The syntax varies depending on the language.

Examples¶

# If the exported value assigns a constant or constant expression,
# the type will be inferred and used in the editor.

@export var number = 5

# If there's no default value, you can add a type to the variable.

@export var number: int

# Export works with resource types.

@export var character_face: Texture
@export var scene_file: PackedScene
# There are many resource types that can be used this way, try e.g.
# the following to list them:
@export var resource: Resource

# Integers and strings hint enumerated values.

# Editor will enumerate as 0, 1 and 2.
@export_enum("Warrior", "Magician", "Thief") var character_class
# If type is String, editor will enumerate with string names.
@export_enum("Rebecca", "Mary", "Leah") var character_name: String

# Named enum values

# Editor will enumerate as THING_1, THING_2, ANOTHER_THING.
enum NamedEnum {THING_1, THING_2, ANOTHER_THING = -1}
@export var x: NamedEnum

# Strings as paths

# String is a path to a file.
@export_file var f
# String is a path to a directory.
@export_dir var f
# String is a path to a file, custom filter provided as hint.
@export_file("*.txt") var f

# Using paths in the global filesystem is also possible,
# but only in scripts in tool mode.

# String is a path to a PNG file in the global filesystem.
@export_global_file("*.png") var tool_image
# String is a path to a directory in the global filesystem.
@export_global_dir var tool_dir

# The multiline annotation tells the editor to show a large input
# field for editing over multiple lines.
@export_multiline var text

# Limiting editor input ranges

# Allow integer values from 0 to 20.
@export_range(0, 20) var i
# Allow integer values from -10 to 20.
@export_range(-10, 20) var j
# Allow floats from -10 to 20 and snap the value to multiples of 0.2.
@export_range(-10, 20, 0.2) var k: float
# The limits can be only for the slider if you add the hints "or_greater" and/or "or_lesser".
@export_range(0, 100, 1, "or_greater", "or_lesser")
# Allow values 'y = exp(x)' where 'y' varies between 100 and 1000
# while snapping to steps of 20. The editor will present a
# slider for easily editing the value.
@export_exp_range(100, 1000, 20) var l

# Floats with easing hint

# Display a visual representation of the 'ease()' function
# when editing.
@export_exp_easing var transition_speed

# Colors

# Regular color given as red-green-blue-alpha value.
@export var col: Color
# Color given as red-green-blue value (alpha will always be 1).
@export_color_no_alpha var col: Color

# Nodes

# Another node in the scene can be exported as a NodePath.
@export var node_path: NodePath
# Do take note that the node itself isn't being exported -
# there is one more step to call the true node:
var node = get_node(node_path)
# If you want to limit the types of nodes, you can use the @export_node_path annotation.
@export_node_path(Button, TouchScreenButton) var some_button

# Resources

@export var resource: Resource
# In the Inspector, you can then drag and drop a resource file
# from the FileSystem dock into the variable slot.

# Opening the inspector dropdown may result in an
# extremely long list of possible classes to create, however.
# Therefore, if you specify an extension of Resource such as:
@export var resource: AnimationNode
# The drop-down menu will be limited to AnimationNode and all
# its inherited classes.

It must be noted that even if the script is not being run while in the editor, the exported properties are still editable. This can be used in conjunction with a script in "tool" mode.

Exporting bit flags¶

Integers used as bit flags can store multiple true/false (boolean) values in one property. By using the @export_flags annotation, they can be set from the editor:

# Set any of the given flags from the editor.
@export_flags("Fire", "Water", "Earth", "Wind") var spell_elements = 0

You must provide a string description for each flag. In this example, Fire has value 1, Water has value 2, Earth has value 4 and Wind corresponds to value 8. Usually, constants should be defined accordingly (e.g. const ELEMENT_WIND = 8 and so on).

Export annotations are also provided for the physics and render layers defined in the project settings:

@export_flags_2d_physics var layers_2d_physics
@export_flags_2d_render var layers_2d_render
@export_flags_3d_physics var layers_3d_physics
@export_flags_3d_render var layers_3d_render

Using bit flags requires some understanding of bitwise operations. If in doubt, use boolean variables instead.

Exporting arrays¶

Exported arrays can have initializers, but they must be constant expressions.

If the exported array specifies a type which inherits from Resource, the array values can be set in the inspector by dragging and dropping multiple files from the FileSystem dock at once.

# Default value must be a constant expression.

export var a = [1, 2, 3]

# Exported arrays can specify type (using the same hints as before).

export(Array, int) var ints = [1, 2, 3]
export(Array, int, "Red", "Green", "Blue") var enums = [2, 1, 0]
export(Array, Array, float) var two_dimensional = [[1.0, 2.0], [3.0, 4.0]]

# You can omit the default value, but then it would be null if not assigned.

export(Array) var b
export(Array, PackedScene) var scenes

# Arrays with specified types which inherit from resource can be set by
# drag-and-dropping multiple files from the FileSystem dock.

export(Array, Texture) var textures
export(Array, PackedScene) var scenes

# Typed arrays also work, only initialized empty:

export var vector3s = PackedVector3Array()
export var strings = PackedStringArray()

# Default value can include run-time values, but can't
# be exported.

var c = [a, 2, 3]

Setting exported variables from a tool script¶

When changing an exported variable's value from a script in Properties, the value in the inspector won't be updated automatically. To update it, call property_list_changed_notify() after setting the exported variable's value.

Advanced exports¶

Not every type of export can be provided on the level of the language itself to avoid unnecessary design complexity. The following describes some more or less common exporting features which can be implemented with a low-level API.

Before reading further, you should get familiar with the way properties are handled and how they can be customized with _set(), _get(), and _get_property_list() methods as described in Accessing data or logic from an object.