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Engine

Inherits: Object

Provides access to engine properties.

Description

The Engine singleton allows you to query and modify the project's run-time parameters, such as frames per second, time scale, and others. It also stores information about the current build of Redot, such as the current version.

Properties

int

max_fps

0

int

max_physics_steps_per_frame

8

float

physics_jitter_fix

0.5

int

physics_ticks_per_second

60

bool

print_error_messages

true

bool

print_to_stdout

true

float

time_scale

1.0

Methods

String

get_architecture_name() const

Dictionary

get_author_info() const

Array[Dictionary]

get_copyright_info() const

Dictionary

get_donor_info() const

int

get_frames_drawn()

float

get_frames_per_second() const

Dictionary

get_redot_author_info() const

Dictionary

get_redot_compatible_version_info() const

Dictionary

get_redot_donor_info() const

Dictionary

get_license_info() const

String

get_license_text() const

MainLoop

get_main_loop() const

int

get_physics_frames() const

float

get_physics_interpolation_fraction() const

int

get_process_frames() const

ScriptLanguage

get_script_language(index: int) const

int

get_script_language_count()

Object

get_singleton(name: StringName) const

PackedStringArray

get_singleton_list() const

Dictionary

get_version_info() const

String

get_write_movie_path() const

bool

has_singleton(name: StringName) const

bool

is_editor_hint() const

bool

is_in_physics_frame() const

Error

register_script_language(language: ScriptLanguage)

void

register_singleton(name: StringName, instance: Object)

Error

unregister_script_language(language: ScriptLanguage)

void

unregister_singleton(name: StringName)

Property Descriptions

int max_fps = 0 🔗

  • void set_max_fps(value: int)

  • int get_max_fps()

The maximum number of frames that can be rendered every second (FPS). A value of 0 means the framerate is uncapped.

Limiting the FPS can be useful to reduce the host machine's power consumption, which reduces heat, noise emissions, and improves battery life.

If ProjectSettings.display/window/vsync/vsync_mode is Enabled or Adaptive, the setting takes precedence and the max FPS number cannot exceed the monitor's refresh rate.

If ProjectSettings.display/window/vsync/vsync_mode is Enabled, on monitors with variable refresh rate enabled (G-Sync/FreeSync), using an FPS limit a few frames lower than the monitor's refresh rate will reduce input lag while avoiding tearing.

See also physics_ticks_per_second and ProjectSettings.application/run/max_fps.

Note: The actual number of frames per second may still be below this value if the CPU or GPU cannot keep up with the project's logic and rendering.

Note: If ProjectSettings.display/window/vsync/vsync_mode is Disabled, limiting the FPS to a high value that can be consistently reached on the system can reduce input lag compared to an uncapped framerate. Since this works by ensuring the GPU load is lower than 100%, this latency reduction is only effective in GPU-bottlenecked scenarios, not CPU-bottlenecked scenarios.

int max_physics_steps_per_frame = 8 🔗

  • void set_max_physics_steps_per_frame(value: int)

  • int get_max_physics_steps_per_frame()

The maximum number of physics steps that can be simulated each rendered frame.

Note: The default value is tuned to prevent expensive physics simulations from triggering even more expensive simulations indefinitely. However, the game will appear to slow down if the rendering FPS is less than 1 / max_physics_steps_per_frame of physics_ticks_per_second. This occurs even if delta is consistently used in physics calculations. To avoid this, increase max_physics_steps_per_frame if you have increased physics_ticks_per_second significantly above its default value.

float physics_jitter_fix = 0.5 🔗

  • void set_physics_jitter_fix(value: float)

  • float get_physics_jitter_fix()

How much physics ticks are synchronized with real time. If 0 or less, the ticks are fully synchronized. Higher values cause the in-game clock to deviate more from the real clock, but they smooth out framerate jitters.

Note: The default value of 0.5 should be good enough for most cases; values above 2 could cause the game to react to dropped frames with a noticeable delay and are not recommended.

Note: When using a custom physics interpolation solution, or within a network game, it's recommended to disable the physics jitter fix by setting this property to 0.

int physics_ticks_per_second = 60 🔗

  • void set_physics_ticks_per_second(value: int)

  • int get_physics_ticks_per_second()

The number of fixed iterations per second. This controls how often physics simulation and Node._physics_process methods are run. This value should generally always be set to 60 or above, as Redot doesn't interpolate the physics step. As a result, values lower than 60 will look stuttery. This value can be increased to make input more reactive or work around collision tunneling issues, but keep in mind doing so will increase CPU usage. See also max_fps and ProjectSettings.physics/common/physics_ticks_per_second.

Note: Only max_physics_steps_per_frame physics ticks may be simulated per rendered frame at most. If more physics ticks have to be simulated per rendered frame to keep up with rendering, the project will appear to slow down (even if delta is used consistently in physics calculations). Therefore, it is recommended to also increase max_physics_steps_per_frame if increasing physics_ticks_per_second significantly above its default value.

bool print_error_messages = true 🔗

  • void set_print_error_messages(value: bool)

  • bool is_printing_error_messages()

If false, stops printing error and warning messages to the console and editor Output log. This can be used to hide error and warning messages during unit test suite runs. This property is equivalent to the ProjectSettings.application/run/disable_stderr project setting.

Note: This property does not impact the editor's Errors tab when running a project from the editor.

Warning: If set to false anywhere in the project, important error messages may be hidden even if they are emitted from other scripts. In a @tool script, this will also impact the editor itself. Do not report bugs before ensuring error messages are enabled (as they are by default).

bool print_to_stdout = true 🔗

  • void set_print_to_stdout(value: bool)

  • bool is_printing_to_stdout()

If false, stops printing messages (for example using @GlobalScope.print) to the console, log files, and editor Output log. This property is equivalent to the ProjectSettings.application/run/disable_stdout project setting.

Note: This does not stop printing errors or warnings produced by scripts to the console or log files, for more details see print_error_messages.

float time_scale = 1.0 🔗

  • void set_time_scale(value: float)

  • float get_time_scale()

The speed multiplier at which the in-game clock updates, compared to real time. For example, if set to 2.0 the game runs twice as fast, and if set to 0.5 the game runs half as fast.

This value affects Timer, SceneTreeTimer, and all other simulations that make use of delta time (such as Node._process and Node._physics_process).

Note: It's recommended to keep this property above 0.0, as the game may behave unexpectedly otherwise.

Note: This does not affect audio playback speed. Use AudioServer.playback_speed_scale to adjust audio playback speed independently of time_scale.

Note: This does not automatically adjust physics_ticks_per_second. With values above 1.0 physics simulation may become less precise, as each physics tick will stretch over a larger period of engine time. If you're modifying time_scale to speed up simulation by a large factor, consider also increasing physics_ticks_per_second to make the simulation more reliable.

Method Descriptions

String get_architecture_name() const 🔗

Returns the name of the CPU architecture the Redot binary was built for. Possible return values include "x86_64", "x86_32", "arm64", "arm32", "rv64", "riscv", "ppc64", "ppc", "wasm64", and "wasm32".

To detect whether the current build is 64-bit, you can use the fact that all 64-bit architecture names contain 64 in their name:

if "64" in Engine.get_architecture_name():
    print("Running a 64-bit build of Redot.")
else:
    print("Running a 32-bit build of Redot.")

Note: This method does not return the name of the system's CPU architecture (like OS.get_processor_name). For example, when running an x86_32 Redot binary on an x86_64 system, the returned value will still be "x86_32".

Dictionary get_author_info() const 🔗

Returns the engine author information as a Dictionary, where each entry is an Array of strings with the names of notable contributors to the Redot Engine: lead_developers, founders, project_managers, and developers.

See also get_redot_author_info for Redot's author info.

Returns an Array of dictionaries with copyright information for every component of Redot's source code.

Every Dictionary contains a name identifier, and a parts array of dictionaries. It describes the component in detail with the following entries:

  • files - Array of file paths from the source code affected by this component;

  • copyright - Array of owners of this component;

  • license - The license applied to this component (such as "Expat" or "CC-BY-4.0").

Dictionary get_donor_info() const 🔗

Returns a Dictionary of categorized donor names. Each entry is an Array of strings:

{platinum_sponsors, gold_sponsors, silver_sponsors, bronze_sponsors, mini_sponsors, gold_donors, silver_donors, bronze_donors}

See also get_redot_donor_info for Redot's donor info.

Warning: All donor names are empty. This currently maintained for compatibility with Redot.

int get_frames_drawn() 🔗

Returns the total number of frames drawn since the engine started.

Note: On headless platforms, or if rendering is disabled with --disable-render-loop via command line, this method always returns 0. See also get_process_frames.

float get_frames_per_second() const 🔗

Returns the average frames rendered every second (FPS), also known as the framerate.

Dictionary get_redot_author_info() const 🔗

Returns the engine author information for Redot as a Dictionary, where each entry is an Array of strings with the names of notable contributors to the Redot Engine: lead_developers, founders, project_managers, and developers.

See also get_author_info for Redot's author info.

Dictionary get_redot_compatible_version_info() const 🔗

Returns the current engine minimal version compatibility info in relation to Redot as a Dictionary containing the following entries:

  • major - Major version number as an int;

  • minor - Minor version number as an int;

  • patch - Patch version number as an int;

  • hex - Full version encoded as a hexadecimal int with one byte (2 hex digits) per number (see example below);

  • status - Status (such as "beta", "rc1", "rc2", "stable", etc.) as a String;

  • string - major, minor, patch, and status in a single String.

The hex value is encoded as follows, from left to right: one byte for the major, one byte for the minor, one byte for the patch version. For example, "3.1.12" would be 0x03010C.

Note: The hex value is still an int internally, and printing it will give you its decimal representation, which is not particularly meaningful. Use hexadecimal literals for quick version comparisons from code:

if Engine.get_redot_compatible_version_info().hex >= 0x040100:
    pass # Do things specifically based on Redot version 4.1 compatibility or later.
else:
    pass # Do things specific to versions before 4.1.

See also get_version_info for Redot's version info.

Dictionary get_redot_donor_info() const 🔗

Returns a Dictionary of categorized donor names for Redot. Each entry is an Array of strings:

{platinum_sponsors, gold_sponsors, silver_sponsors, bronze_sponsors, mini_sponsors, gold_donors, silver_donors, bronze_donors}

See also get_donor_info for Redot's donor info.

Dictionary get_license_info() const 🔗

Returns a Dictionary of licenses used by Redot and included third party components. Each entry is a license name (such as "Expat") and its associated text.

String get_license_text() const 🔗

Returns the full Redot license text.

MainLoop get_main_loop() const 🔗

Returns the instance of the MainLoop. This is usually the main SceneTree and is the same as Node.get_tree.

Note: The type instantiated as the main loop can changed with ProjectSettings.application/run/main_loop_type.

int get_physics_frames() const 🔗

Returns the total number of frames passed since the engine started. This number is increased every physics frame. See also get_process_frames.

This method can be used to run expensive logic less often without relying on a Timer:

func _physics_process(_delta):
    if Engine.get_physics_frames() % 2 == 0:
        pass # Run expensive logic only once every 2 physics frames here.

float get_physics_interpolation_fraction() const 🔗

Returns the fraction through the current physics tick we are at the time of rendering the frame. This can be used to implement fixed timestep interpolation.

int get_process_frames() const 🔗

Returns the total number of frames passed since the engine started. This number is increased every process frame, regardless of whether the render loop is enabled. See also get_frames_drawn and get_physics_frames.

This method can be used to run expensive logic less often without relying on a Timer:

func _process(_delta):
    if Engine.get_process_frames() % 5 == 0:
        pass # Run expensive logic only once every 5 process (render) frames here.

ScriptLanguage get_script_language(index: int) const 🔗

Returns an instance of a ScriptLanguage with the given index.

int get_script_language_count() 🔗

Returns the number of available script languages. Use with get_script_language.

Object get_singleton(name: StringName) const 🔗

Returns the global singleton with the given name, or null if it does not exist. Often used for plugins. See also has_singleton and get_singleton_list.

Note: Global singletons are not the same as autoloaded nodes, which are configurable in the project settings.

PackedStringArray get_singleton_list() const 🔗

Returns a list of names of all available global singletons. See also get_singleton.

Dictionary get_version_info() const 🔗

Returns the current engine version information as a Dictionary containing the following entries:

  • major - Major version number as an int;

  • minor - Minor version number as an int;

  • patch - Patch version number as an int;

  • hex - Full version encoded as a hexadecimal int with one byte (2 hex digits) per number (see example below);

  • status - Status (such as "beta", "rc", "stable", etc.) as a String;

  • status_version - Status version number as an int, 0 if status is "stable";

  • build - Build name (e.g. "custom_build") as a String;

  • hash - Full Git commit hash as a String;

  • timestamp - Holds the Git commit date UNIX timestamp in seconds as an int, or 0 if unavailable;

  • string - major, minor, patch, status, and build in a single String.

The hex value is encoded as follows, from left to right: one byte for the major, one byte for the minor, one byte for the patch version. For example, "3.1.12" would be 0x03010C.

Note: The hex value is still an int internally, and printing it will give you its decimal representation, which is not particularly meaningful. Use hexadecimal literals for quick version comparisons from code:

if Engine.get_version_info().hex >= 0x040100:
    pass # Do things specific to version 4.1 or later.
else:
    pass # Do things specific to versions before 4.1.

See also get_redot_compatible_version_info for Redot's minimal compatibility version info.

String get_write_movie_path() const 🔗

Returns the path to the MovieWriter's output file, or an empty string if the engine wasn't started in Movie Maker mode. The default path can be changed in ProjectSettings.editor/movie_writer/movie_file.

bool has_singleton(name: StringName) const 🔗

Returns true if a singleton with the given name exists in the global scope. See also get_singleton.

print(Engine.has_singleton("OS"))          # Prints true
print(Engine.has_singleton("Engine"))      # Prints true
print(Engine.has_singleton("AudioServer")) # Prints true
print(Engine.has_singleton("Unknown"))     # Prints false

Note: Global singletons are not the same as autoloaded nodes, which are configurable in the project settings.

bool is_editor_hint() const 🔗

Returns true if the script is currently running inside the editor, otherwise returns false. This is useful for @tool scripts to conditionally draw editor helpers, or prevent accidentally running "game" code that would affect the scene state while in the editor:

if Engine.is_editor_hint():
    draw_gizmos()
else:
    simulate_physics()

See Running code in the editor in the documentation for more information.

Note: To detect whether the script is running on an editor build (such as when pressing F5), use OS.has_feature with the "editor" argument instead. OS.has_feature("editor") evaluate to true both when the script is running in the editor and when running the project from the editor, but returns false when run from an exported project.

bool is_in_physics_frame() const 🔗

Returns true if the engine is inside the fixed physics process step of the main loop.

func _enter_tree():
    # Depending on when the node is added to the tree,
    # prints either "true" or "false".
    print(Engine.is_in_physics_frame())

func _process(delta):
    print(Engine.is_in_physics_frame()) # Prints false

func _physics_process(delta):
    print(Engine.is_in_physics_frame()) # Prints true

Error register_script_language(language: ScriptLanguage) 🔗

Registers a ScriptLanguage instance to be available with ScriptServer.

Returns:

void register_singleton(name: StringName, instance: Object) 🔗

Registers the given Object instance as a singleton, available globally under name. Useful for plugins.

Error unregister_script_language(language: ScriptLanguage) 🔗

Unregisters the ScriptLanguage instance from ScriptServer.

Returns:

void unregister_singleton(name: StringName) 🔗

Removes the singleton registered under name. The singleton object is not freed. Only works with user-defined singletons registered with register_singleton.