11 min read

Source: Roblox Creator Hub · CC BY 4.0 · View source · Code samples: MIT Imported 2026-10-03. Formatting adapted for this site.

Actor

Inherits from: Model → PVInstance → Instance → Object

An Actor is a container for code that can be safely split into its own thread using task.desynchronize(). It should also contain the instances used by its scripts.

To learn more about using multiple Actors to optimize script performance, see Parallel Luau.

Notes

Each Actor runs in its own Luau VM. ModuleScripts required by an Actor are not shared or cached across Actors or with the main thread. Each VM executes its own copy of the module, so module-level state is isolated per Actor. Design accordingly if your modules hold state you intend to share.
script:GetActor() returns nil when called from a ModuleScript unless the ModuleScript is a descendant of the Actor. ModuleScripts stored elsewhere (for example, ReplicatedStorage) and required by an Actor are not considered descendants of the Actor.

Inherits from: Model

Memory category: BaseParts

Methods

Name	Type / Returns	Description
Actor:BindToMessage	RBXScriptConnection	Binds a Luau callback to a message with the specified topic.
Actor:BindToMessageParallel	RBXScriptConnection	Binds a Luau callback to a message with the specified topic.
Actor:SendMessage	()	Sends a message to an Actor.

Inherited from Model

Name	Type / Returns	Description
Model:AddPersistentPlayer	()	Sets this model to be persistent for the specified player. `ModelStreamingMode` must be set to `PersistentPerPlayer` for behavior to be changed as a result of addition.
Model:BreakJoints	()	Breaks connections between `BaseParts`, including surface connections with any adjacent parts, `WeldConstraints` and all `Welds` and other `JointInstances`.
Model:breakJoints	()
Model:GetBoundingBox	Tuple	Returns a description of a volume that contains all parts of a Model.
Model:GetExtentsSize	Vector3	Returns the size of the smallest bounding box that contains all of the `BaseParts` in the `Model`, aligned with the `Model.PrimaryPart` if it is set.
Model:GetModelCFrame	CFrame	This value historically returned the CFrame of a central position in the model.
Model:GetModelSize	Vector3	Returns the Vector3 size of the Model.
Model:GetPersistentPlayers	List	Returns all the `Player` objects that this model object is persistent for. Behavior varies based on whether this method is called from a `Script` or a `LocalScript`.
Model:GetPrimaryPartCFrame	CFrame	Returns the `CFrame` of the model's `Model.PrimaryPart`. This function will throw an error if no primary part exists for the `Model`.
Model:GetScale	float	Returns the canonical scale of the model, which defaults to 1 for newly created models and will change as it is scaled via `Model:ScaleTo()`.
Model:MakeJoints	()	Goes through all `BaseParts` in the `Model`. If any part's side has a SurfaceType that can make a joint it will create a joint with any adjacent parts.
Model:makeJoints	()
Model:move	()
Model:MoveTo	()	Moves the `PrimaryPart` to the given position. If a primary part has not been specified, the root part of the model will be used.
Model:moveTo	()
Model:RemovePersistentPlayer	()	Makes this model no longer persistent for the specified player. `ModelStreamingMode` must be set to `PersistentPerPlayer` for behavior to be changed as a result of removal.
Model:ResetOrientationToIdentity	()	Resets the rotation of the model's parts to the previously set identity rotation, which is done through the `Model:SetIdentityOrientation()` method.
Model:ScaleTo	()	Sets the scale factor of the model, adjusting the sizing and location of all descendant Instances such that they have that scale factor relative to their initial sizes and locations when scale factor was 1.
Model:SetIdentityOrientation	()	Sets the identity rotation of the given model, allowing you to reset the rotation of the entire model later, through the use of the `ResetOrientationToIdentity` method.
Model:SetPrimaryPartCFrame	()	Sets the `BasePart.CFrame` of the model's `Model.PrimaryPart`. All other parts in the model will also be moved and will maintain their orientation and offset respective to the `Model.PrimaryPart`.
Model:TranslateBy	()	Shifts a `Model` by the given `Vector3` offset, preserving the model's orientation. If another `BasePart` or `Terrain` already exists at the new position then the `Model` will overlap said object.

Inherited from PVInstance

Name	Type / Returns	Description
PVInstance:GetPivot	CFrame	Gets the pivot of a `PVInstance`.
PVInstance:PivotTo	()	Transforms the `PVInstance` along with all of its descendant `PVInstances` such that the pivot is now located at the specified `CFrame`.

Inherited from Instance

Name	Type / Returns	Description
Instance:AddTag	()	Applies a tag to the instance.
Instance:children	Instances	Returns an array of the object's children.
Instance:ClearAllChildren	()	This method destroys all of an instance's children.
Instance:Clone	Instance	Create a copy of an instance and all its descendants, ignoring instances that are not `Archivable`.
Instance:clone	Instance
Instance:Destroy	()	Sets the `Instance.Parent` property to `nil`, locks the `Instance.Parent` property, disconnects all connections, and calls `Destroy()` on all children.
Instance:destroy	()
Instance:FindFirstAncestor	Instance?	Returns the first ancestor of the `Instance` whose `Instance.Name` is equal to the given name.
Instance:FindFirstAncestorOfClass	Instance?	Returns the first ancestor of the `Instance` whose `Object.ClassName` is equal to the given className.
Instance:FindFirstAncestorWhichIsA	Instance?	Returns the first ancestor of the `Instance` for whom `Object:IsA()` returns true for the given className.
Instance:FindFirstChild	Instance?	Returns the first child of the `Instance` found with the given name.
Instance:findFirstChild	Instance
Instance:FindFirstChildOfClass	Instance?	Returns the first child of the `Instance` whose `ClassName` is equal to the given class name.
Instance:FindFirstChildWhichIsA	Instance?	Returns the first child of the `Instance` for whom `Object:IsA()` returns true for the given className.
Instance:FindFirstDescendant	Instance?	Returns the first descendant found with the given `Instance.Name`.
Instance:GetActor	Actor?	Returns the `Actor` associated with the Instance, if any.
Instance:GetAttribute	Variant	Returns the value which has been assigned to the given attribute name.
Instance:GetAttributeChangedSignal	RBXScriptSignal	Returns an event that fires when the given attribute changes.
Instance:GetAttributes	Dictionary	Returns a dictionary of the instance's attributes.
Instance:GetChildren	Instances	Returns an array containing all of the instance's children.
Instance:getChildren	Instances
Instance:GetDebugId	string	Returns a coded string of the debug ID used internally by Roblox.
Instance:GetDescendants	Instances	Returns an array containing all of the descendants of the instance.
Instance:GetFullName	string	Returns a string describing the instance's ancestry.
Instance:GetStyled	Variant	Returns the styled or explicitly modified value of the specified property, or else the default property value if it hasn't been styled/modified.
Instance:GetStyledPropertyChangedSignal	RBXScriptSignal	Returns an event that fires when the given style property changes on the instance.
Instance:GetTags	Array	Gets an array of all tags applied to the instance.
Instance:HasTag	boolean	Check whether the instance has a given tag.
Instance:IsAncestorOf	boolean	Returns true if an `Instance` is an ancestor of the given descendant.
Instance:IsDescendantOf	boolean	Returns `true` if an `Instance` is a descendant of the given ancestor.
Instance:isDescendantOf	boolean
Instance:IsPropertyModified	boolean	Returns `true` if the value stored in the specified property is not equal to the code-instantiated default.
Instance:QueryDescendants	Instances	Returns an array containing all descendants of the instance that match the `selector` string.
Instance:Remove	()	Sets the object's `Parent` to `nil`, and does the same for all its descendants.
Instance:remove	()
Instance:RemoveTag	()	Removes a tag from the instance.
Instance:ResetPropertyToDefault	()	Resets a property to its default value.
Instance:SetAttribute	()	Sets the attribute with the given name to the given value.
Instance:WaitForChild	Instance	Returns the child of the `Instance` with the given name. If the child does not exist, it will yield the current thread until it does.

Inherited from Object

Name	Type / Returns	Description
Object:GetPropertyChangedSignal	RBXScriptSignal	Get an event that fires when a given property of the object changes.
Object:IsA	boolean	Returns true if an object's class matches or inherits from a given class.
Object:isA	boolean

Actor:BindToMessage

This method is used to bind a Luau callback to a message with the specified topic. When a message is sent (using SendMessage()) to the topic specified the provided callback will be called in a serial execution context.

Multiple Luau callbacks may be bound to a single actor and even to a single message topic.

Note: Only the scripts which are descendants of an Actor may bind to its messages.

Parameters

Name	Type	Default	Description
topic	string		The topic used to identify the type of message.
function	Function		The Luau callback to invoke when a message with the specified topic is received. The callback receives the message contents as its arguments.

Returns

Type	Description
RBXScriptConnection	This connection object may be used to disconnect the Luau callback from receiving messages.

Field	Value
security	None
thread safety	Safe
capabilities	["Basic"]

Code samples: View on Creator Hub (Actor-BindToMessage).

Actor:BindToMessageParallel

Multiple Luau callbacks may be bound to a single actor and even to a single message topic.

Note: Only the scripts which are descendants of an Actor may bind to its messages.

Parameters

Name	Type	Default	Description
topic	string		The topic used to identify the type of message.
function	Function		The Luau callback to invoke when a message with the specified topic is received. The callback receives the message contents as its arguments.

Returns

Type	Description
RBXScriptConnection	This connection object may be used to disconnect the Luau callback from receiving messages.

Field	Value
security	None
thread safety	Safe
capabilities	["Basic"]

Code samples: View on Creator Hub (Actor-BindToMessageParallel).

Actor:SendMessage

Sends a message to an Actor. Messages are sent asynchronously, so the sender will not block or yield when calling the SendMessage() method.

Since a single Actor may receive different kinds of messages, a topic parameter is used to distinguish between various kinds of messages.

See BindToMessage() for details on receiving a message sent using SendMessage().

Note that message arguments are passed by copy across Luau VM boundaries, not by reference. Sending large tables incurs a full copy on each call. Functions are bound to a specific VM and cannot be passed in messages.

Parameters

Name	Type	Default	Description
topic	string		The topic used to identify the message being sent.
message	Tuple		The contents of the message to send to the Actor.

Returns

Type	Description
()

Field	Value
security	None
thread safety	Safe
capabilities	["Basic"]

Code samples: View on Creator Hub (Actor-SendMessage).

Properties

Inherited from Model

Name	Type / Returns	Description
Model.LevelOfDetail	ModelLevelOfDetail	Sets the level of detail on the model for experiences with instance streaming enabled.
Model.ModelStreamingMode	ModelStreamingMode	Controls the model streaming behavior on `Models` when instance streaming is enabled.
Model.PrimaryPart	BasePart	The primary part of the `Model`, or `nil` if not explicitly set.
Model.Scale	float	Editor-only property used to scale the model around its pivot. Setting this property will move the scale as though `Model:ScaleTo()` was called on it.
Model.WorldPivot	CFrame	Determines where the pivot of a `Model` which does not have a set `Model.PrimaryPart` is located.

Inherited from PVInstance

Name	Type / Returns	Description
PVInstance.Origin	CFrame	Editor-only property that reads and sets the world `CFrame` of the `PVInstance`'s pivot, moving the entire instance when changed from the Studio Properties window.
PVInstance.Pivot Offset	CFrame	Editor-only property that displays and edits the pivot's `CFrame` relative to the instance, moving only the pivot and leaving the instance in place.

Inherited from Instance

Name	Type / Returns	Description
Instance.Archivable	boolean	Determines if an `Instance` and its descendants can be cloned using `Instance:Clone()`, and can be saved/published.
Instance.archivable	boolean
Instance.Capabilities	SecurityCapabilities	The set of capabilities allowed to be used for scripts inside this container.
Instance.IsInSandbox	boolean	Indicates whether the instance is inside a sandboxed container.
Instance.Name	string	A non-unique identifier of the `Instance`.
Instance.Parent	Instance	Determines the hierarchical parent of the `Instance`.
Instance.PredictionMode	PredictionMode	Reflects the client-side prediction mode applied to the instance under server-authoritative physics.
Instance.RobloxLocked	boolean	A deprecated property that used to protect `CoreGui` objects.
Instance.Sandboxed	boolean	When enabled, the instance can only access abilities in its `Capabilities` list.
Instance.UniqueId	UniqueId	A unique identifier for the instance.

Inherited from Object

Name	Type / Returns	Description
Object.ClassName	string	A read-only string representing the class this `Object` belongs to.
Object.className	string

Events

Inherited from Instance

Name	Type / Returns	Description
Instance.AncestryChanged		Fires when the `Instance.Parent` property of this object or one of its ancestors is changed.
Instance.AttributeChanged		Fires whenever an attribute is changed on the `Instance`.
Instance.ChildAdded		Fires after an object is parented to this `Instance`.
Instance.childAdded
Instance.ChildRemoved		Fires after a child is removed from this `Instance`.
Instance.DescendantAdded		Fires after a descendant is added to the `Instance`.
Instance.DescendantRemoving		Fires immediately before a descendant of the `Instance` is removed.
Instance.Destroying		Fires immediately before (or is deferred until after) the instance is destroyed via `Instance:Destroy()`.
Instance.StyledPropertiesChanged		Fires whenever any style property is changed on the instance, including when a property is set to `nil`.

Inherited from Object

Name	Type / Returns	Description
Object.Changed		Fires immediately after a property of the object changes, with some limitations.