Updatelooper

Based on game build 714014 | Last updated: 2026-03-03

Overview

UpdateLooper provides a flexible mechanism for attaching multiple update callbacks to an entity at different update phases: per-frame (OnUpdate), long-interval (LongUpdate), wall-logic (OnWallUpdate), and post-update (PostUpdate). It exists because DoPeriodicTask(0) does not guarantee frame-precise execution. Each entity that uses this component can register arbitrary functions to be called at these phases, and the component intelligently starts/stops entity updates only when needed.

Usage example

local inst = CreateEntity()
inst:AddComponent("updatelooper")

-- Register per-frame callbacks
inst.components.updatelooper:AddOnUpdateFn(function(ent, dt)
    -- runs every frame
end)

-- Register long-interval callbacks
inst.components.updatelooper:AddLongUpdateFn(function(ent, dt)
    -- runs less frequently (e.g., every 0.5 seconds via engine)
end)

-- Register post-update callbacks
inst.components.updatelooper:AddPostUpdateFn(function(ent)
    -- runs after all per-frame updates are complete
end)

Dependencies & tags

Components used: None identified
Tags: Adds no tags; relies on internal update registration via StartUpdatingComponent, StartWallUpdatingComponent, and _PostUpdates registry.

Properties

Property	Type	Default Value	Description
inst	Entity	nil (set in constructor)	The entity instance this component is attached to.
onupdatefns	table	{}	List of per-frame callback functions.
longupdatefns	table	{}	List of long-interval callback functions.
onwallupdatefns	table	{}	List of wall-update callback functions.
postupdatefns	table	{}	List of post-update callback functions.
OnUpdatesToRemove	table?	nil	Temporary list of functions pending removal during per-frame update.
OnLongUpdatesToRemove	table?	nil	Temporary list of functions pending removal during long update.
OnWallUpdatesToRemove	table?	nil	Temporary list of functions pending removal during wall update.

Main functions

AddOnUpdateFn(fn)

• Description: Registers a per-frame callback to be called on every entity update. Automatically starts per-frame updates if none were registered.
• Parameters: fn (function) - Callback function taking (entity, dt) where dt is delta time in seconds.
• Returns: Nothing.

RemoveOnUpdateFn(fn)

• Description: Schedules a per-frame callback for removal. Safe to call during an active update loop.
• Parameters: fn (function) - The callback to remove.
• Returns: Nothing.
• Error states: No-op if fn is not currently registered.

AddLongUpdateFn(fn)

• Description: Registers a long-interval callback (typically called at longer intervals by the engine, e.g., 0.5s).
• Parameters: fn (function) - Callback function taking (entity, dt).
• Returns: Nothing.

RemoveLongUpdateFn(fn)

• Description: Schedules a long-interval callback for removal.
• Parameters: fn (function) - The callback to remove.
• Returns: Nothing.

AddOnWallUpdateFn(fn)

• Description: Registers a wall-update callback. Starts wall-updating if needed. Only runs on the server.
• Parameters: fn (function) - Callback function taking (entity, dt).
• Returns: Nothing.

RemoveOnWallUpdateFn(fn)

• Description: Schedules a wall-update callback for removal.
• Parameters: fn (function) - The callback to remove.
• Returns: Nothing.

AddPostUpdateFn(fn)

• Description: Registers a post-update callback. Post-updates occur after all per-frame updates have completed in a given tick. Ensures safe concurrent modification of callbacks during iteration.
• Parameters: fn (function) - Callback function taking (entity).
• Returns: Nothing.

RemovePostUpdateFn(fn)

• Description: Removes a post-update callback. Can safely remove during a PostUpdate loop; otherwise performs immediate removal and compaction.
• Parameters: fn (function) - The callback to remove.
• Returns: Nothing.

Events & listeners

None identified
(Note: This component does not register or emit events via inst:ListenForEvent / inst:PushEvent; it integrates with the engine’s update loop via StartUpdatingComponent, StartWallUpdatingComponent, and the global _PostUpdates table.)