LoadingSceneProgressBar

Defined in: ui/src/LoadingSceneProgressBar.ts:56

Ready-made loading progress bar for use inside a LoadingScene.

Spawn it from the scene’s onEnter, then call this.startLoading() to kick off the load:

class Boot extends LoadingScene {
  readonly target = new GameScene();
  override onEnter() {
    this.spawn(LoadingSceneProgressBar);
    this.startLoading();
  }
}

Subscribes to scene:loading:progress internally and updates a UIProgressBar. For spinners, animated text, or other custom visuals, write your own component that subscribes to the same event.

Extends

Entity

Constructors

Constructor

new LoadingSceneProgressBar(name?, tags?): LoadingSceneProgressBar

Defined in: core/dist/index.d.ts:362

Parameters

name?

string

tags?

Iterable<string, any, any>

Returns

LoadingSceneProgressBar

Inherited from

Entity.constructor

Properties

fixedUpdate?

readonly optional fixedUpdate?: undefined

Defined in: core/dist/index.d.ts:334

Reserved: a subclass that declares fixedUpdate fails to compile.

There is no fixed-step entity hook either, and for the same reason. Both homes above apply: a component added to the entity, or a process on the queue that makeSceneScopedQueue() returns when the work outlives a single entity.

The slot is optional, so the compiler reports the subclass method as not assignable to type undefined rather than to type never.

Inherited from

Entity.fixedUpdate

id

readonly id: number

Defined in: core/dist/index.d.ts:285

Unique auto-incrementing ID.

Inherited from

Entity.id

key?

readonly optional key?: string

Defined in: core/dist/index.d.ts:296

Stable identity key, scene-scoped. Set at spawn-time when options.key is passed to scene.spawn / entity.spawnChild; undefined otherwise. Used with scene.findByKey and as a stable id in reactive stores (e.g. a createSet<string>() persisted under "world.opened").

Inherited from

Entity.key

name

readonly name: string

Defined in: core/dist/index.d.ts:287

Display name for debugging.

Inherited from

Entity.name

timeScale

timeScale: number

Defined in: core/dist/index.d.ts:310

Per-entity time-scale multiplier. Mirrors Scene.timeScale but scoped to this single entity: the engine composes the delta time passed to this entity’s components (and its ProcessComponent, particle emitters) as dt * scene.timeScale * entity.timeScale. 1 = normal speed, 0.5 = half speed, 0 = frozen, 2 = double speed.

Physics is deliberately NOT affected: PhysicsSystem steps a single shared Rapier world per scene under scene.timeScale only, so a rigid-body entity’s simulation cannot be individually slowed or sped up via this field. Use a kinematic body or scale velocities manually if you need per-body time control.

Inherited from

Entity.timeScale

update?

readonly optional update?: undefined

Defined in: core/dist/index.d.ts:322

Reserved: a subclass that declares update fails to compile.

The engine’s per-frame pass ticks the components an entity holds, so an entity method with this name is dead code. Per-frame logic belongs in a component added to the entity, or in a process on the queue that makeSceneScopedQueue() returns when the work outlives a single entity.

The slot is optional, so the compiler reports the subclass method as not assignable to type undefined rather than to type never.

Inherited from

Entity.update

[TRAITS_KEY]

static [TRAITS_KEY]: Set<symbol>

Defined in: core/dist/index.d.ts:283

Inherited from

Entity.[TRAITS_KEY]

Accessors

activeSelf

Get Signature

get activeSelf(): boolean

Defined in: core/dist/index.d.ts:441

This entity’s own activeness bit — what setActive last wrote. An entity whose activeSelf is true can still be dormant, if an ancestor is not. Use isActive for the state the engine acts on.

Returns

boolean

Inherited from

Entity.activeSelf

children

Get Signature

get children(): ReadonlyMap<string, Entity>

Defined in: core/dist/index.d.ts:475

Named children as a read-only map. Empty map if no children.

Returns

ReadonlyMap<string, Entity>

Inherited from

Entity.children

generation

Get Signature

get generation(): number

Defined in: core/dist/index.d.ts:392

Which life of this entity is current. An EntityPool member is reused, so one object serves many lives; the counter moves on whenever a life ends, by release or by destruction. handle compares against it. Compare for equality only — a destruction cascade can advance it more than once, so it does not count lives. Written by the engine only.

Returns

number

Inherited from

Entity.generation

isActive

Get Signature

get isActive(): boolean

Defined in: core/dist/index.d.ts:448

Whether the entity is active: its own activeSelf and every ancestor’s. A dormant entity keeps all of its components and its place in scene.getEntities(), but drops out of queries, findEntity, findEntitiesByTag and findEntities, and its components stop updating.

Returns

boolean

Inherited from

Entity.isActive

isDestroyed

Get Signature

get isDestroyed(): boolean

Defined in: core/dist/index.d.ts:382

True once the entity is dead — after destroy() is called, or once its scene starts tearing it down on scene exit.

Returns

boolean

Inherited from

Entity.isDestroyed

isPooled

Get Signature

get isPooled(): boolean

Defined in: core/dist/index.d.ts:384

True while an EntityPool owns this entity.

Returns

boolean

Inherited from

Entity.isPooled

parent

Get Signature

get parent(): Entity | null

Defined in: core/dist/index.d.ts:473

The parent entity, or null if this is a root entity. A child created by Entity.spawnChild reads null until that call returns, so its setup() cannot reach the parent through it.

Returns

Entity | null

Inherited from

Entity.parent

scene

Get Signature

get scene(): Scene

Defined in: core/dist/index.d.ts:375

The scene this entity belongs to. Throws if the entity is not attached to a scene — which in practice only happens before scene.spawn / addChild wires it up, or after the entity is destroyed (end-of-frame flush after destroy(), or scene teardown on exit). Inside lifecycle methods (setup, component onAdd, update, and component onDestroy during destruction) this is always safe to access.

For the rare case where you genuinely need to inspect whether an entity has a scene (e.g. defensive code in systems iterating a query result), use tryScene instead.

Returns

Scene

Inherited from

Entity.scene

tryScene

Get Signature

get tryScene(): Scene | null

Defined in: core/dist/index.d.ts:377

The scene this entity belongs to, or null if detached.

Returns

Scene | null

Inherited from

Entity.tryScene

Methods

_componentsInUpdateOrder()

_componentsInUpdateOrder(): Iterable<Component>

Defined in: core/dist/index.d.ts:566

Internal

Internal: components in the order ComponentUpdateSystem calls them — ascending updatePriority, ties in add order. Identical to getAll() until a component declares a priority. The sorted array is replaced, not mutated, when a component is added or removed, so a pass already iterating it finishes over the old order; a component added mid-pass first runs next frame. The map iterator on the default path is live, so there a component added mid-pass can run in the same pass.

Returns

Iterable<Component>

Inherited from

Entity._componentsInUpdateOrder

_deactivateForDestroy()

_deactivateForDestroy(): void

Defined in: core/dist/index.d.ts:622

Internal

Internal: deactivate immediately without touching activeSelf, mirroring what destroy() does per-entity. Used by Scene when it tears down every entity at once — idempotent, and safe to call in any order across a flat entity set: an entity already reached through a parent’s cascade is a no-op here.

Returns

void

Inherited from

Entity._deactivateForDestroy

_destroyOwned()

_destroyOwned(): void

Defined in: core/dist/index.d.ts:593

Internal

Internal: destroy for real, skipping the pool redirect. Used by the owning pool when it disposes, and by the cascade below.

Returns

void

Inherited from

Entity._destroyOwned

_detachFromParent()

_detachFromParent(): void

Defined in: core/dist/index.d.ts:649

Internal

Internal: detach from whatever parent this entity has, without touching children or activeness. Shared by _performDestroy, the pooled-child branch of _destroyOwned’s cascade, and EntityPool.stow, which parks a released member that picked up a parent mid-lease. Unlike removeChild, this does not resync activeness — callers that need activeSelf honoured against no parent still call setActive/_resyncActive themselves.

Returns

void

Inherited from

Entity._detachFromParent

_endLife()

_endLife(): void

Defined in: core/dist/index.d.ts:638

Internal

Internal: end this life so handles taken during it stop resolving. The subtree follows, because it is released or destroyed with this entity. Called by EntityPool when a lease ends; destruction goes through _markDestroyed instead.

Returns

void

Inherited from

Entity._endLife

_invalidateUpdateOrder()

_invalidateUpdateOrder(component): void

Defined in: core/dist/index.d.ts:574

Internal

Internal: a component was added or its updatePriority was written. Switches the entity onto the sorted update path once any component leaves the default priority, and drops the cached order so the next update pass rebuilds it.

Parameters

component

Component

Returns

void

Inherited from

Entity._invalidateUpdateOrder

_markDestroyed()

_markDestroyed(): void

Defined in: core/dist/index.d.ts:630

Internal

Internal: mark the entity destroyed without queueing it. Called by Scene during teardown so every entity reads isDestroyed === true before any component onDestroy runs, and by _destroyOwned. Idempotent, and the one place a destruction ends a life.

Returns

void

Inherited from

Entity._markDestroyed

_markPooled()

_markPooled(owner): void

Defined in: core/dist/index.d.ts:435

Internal

Internal: mark the entity as a pool member. Called by EntityPool when it constructs one.

Parameters

owner

EntityPoolOwner

Returns

void

Inherited from

Entity._markPooled

_performDestroy()

_performDestroy(onError?): void

Defined in: core/dist/index.d.ts:655

Internal

Internal: perform actual destruction — remove all components and clear state. Called by Scene during endOfFrame flush.

Parameters

onError?

(error) => void

Returns

void

Inherited from

Entity._performDestroy

_resyncActive()

_resyncActive(): void

Defined in: core/dist/index.d.ts:599

Internal

Internal: recompute effective activeness against the current parent and propagate to descendants. Called after setActive and after a re-parent.

Returns

void

Inherited from

Entity._resyncActive

_setActiveSuppressed()

_setActiveSuppressed(activeSelf): void

Defined in: core/dist/index.d.ts:606

Internal

Internal: write activeSelf and park the entity as dormant without firing hooks or touching queries. Pools and dormant-parent child spawns use this to avoid transient query membership and enable hooks.

Parameters

activeSelf

boolean

Returns

void

Inherited from

Entity._setActiveSuppressed

_setKey()

_setKey(key): void

Defined in: core/dist/index.d.ts:703

Internal

Internal: assign the stable identity key. Called by Scene._registerKey during spawn. Throws if the entity already has a key — keys are immutable for an entity’s lifetime.

Parameters

key

string

Returns

void

Inherited from

Entity._setKey

_setScene()

_setScene(scene, callbacks): void

Defined in: core/dist/index.d.ts:696

Internal

Internal: set the scene and callbacks. Called by Scene.spawn().

Parameters

scene

Scene | null

callbacks

EntityCallbacks | null

Returns

void

Inherited from

Entity._setScene

add()

add<C>(component): C

Defined in: core/dist/index.d.ts:514

Add a component instance. Returns the component for chaining.

Type Parameters

C

C extends Component

Parameters

component

C

Returns

C

Inherited from

Entity.add

addChild()

addChild(name, child): void

Defined in: core/dist/index.d.ts:480

Add a named child entity. Auto-adds to parent’s scene if not already in one; a child that belongs to a different scene is rejected.

Parameters

name

string

child

Entity

Returns

void

Inherited from

Entity.addChild

destroy()

destroy(): void

Defined in: core/dist/index.d.ts:587

Retire the entity. Leaves its queries immediately — isActive reads false and component onDisable fires right away — with the rest of teardown (onDestroy, detach from scene) deferred to the end-of-frame flush.

A pool member is retired by going back to its pool instead — its pool owns its lifetime and destroys it only when the pool itself is disposed. That keeps destroy() usable from the places retirement is actually decided: a collision handler, an update, an event listener, all of which see a plain Entity and hold no pool reference.

Returns

void

Inherited from

Entity.destroy

emit()

Call Signature

emit(token): void

Defined in: core/dist/index.d.ts:543

Emit a typed event on this entity. Bubbles to the scene.

Parameters

token

EventToken<void>

Returns

void

Inherited from

Entity.emit

Call Signature

emit<T>(token, data): void

Defined in: core/dist/index.d.ts:544

Emit a typed event on this entity. Bubbles to the scene.

Type Parameters

T

T

Parameters

token

EventToken<T>

data

T

Returns

void

Inherited from

Entity.emit

get()

get<C>(cls): C

Defined in: core/dist/index.d.ts:521

Get a component by class. An exact match wins; otherwise the single component assignable to cls is returned. Throws when nothing matches, and when several components are assignable to cls — use Entity.getAll for that case.

Type Parameters

C

C extends Component

Parameters

cls

ComponentClass<C>

Returns

C

Inherited from

Entity.get

getAll()

Call Signature

getAll(): Iterable<Component>

Defined in: core/dist/index.d.ts:546

Get all components as an iterable, in add order.

Returns

Iterable<Component>

Inherited from

Entity.getAll

Call Signature

getAll<C>(cls): readonly C[]

Defined in: core/dist/index.d.ts:555

Every component assignable to cls — the class itself and any subclass — in add order. The returned array is a read-only view of the entity’s index: removing a component replaces the list rather than mutating it, so a walk already in flight visits every member it started with. Adding one appends to the live list, so a walk in flight also visits a component added during it.

Type Parameters

C

C extends Component

Parameters

cls

ComponentClass<C>

Returns

readonly C[]

Inherited from

Entity.getAll

getChild()

getChild(name): Entity

Defined in: core/dist/index.d.ts:510

Get a child by name. Throws if not found.

Parameters

name

string

Returns

Entity

Inherited from

Entity.getChild

handle()

handle(): EntityHandle<LoadingSceneProgressBar>

Defined in: core/dist/index.d.ts:422

Capture a reference that expires with this entity’s current life, read back through .current.

class Turret extends Entity {
  private target?: EntityHandle<Enemy>;

  onSpotted(enemy: Enemy) { this.target = enemy.handle(); }

  update() {
    const enemy = this.target?.current;   // undefined once that enemy is gone
    if (enemy) this.aimAt(enemy);
  }
}

Take a handle whenever pooled entities are involved — a member can be retired from anywhere, so a stored plain reference goes stale silently. A plain reference is fine for entities that live as long as the scene, or when the code storing the reference also controls when the entity goes away.

A handle taken outside a live life never resolves: on a pool member (or an entity under one) whose pool is not currently lending it out, or on an entity that is destroyed or sits under a destroyed ancestor. In all of those the caller is holding a reference from a life that is already over.

Returns

EntityHandle<LoadingSceneProgressBar>

Inherited from

Entity.handle

has()

has(cls): boolean

Defined in: core/dist/index.d.ts:531

Check if entity has a component of the given class or any subclass of it.

Parameters

cls

ComponentClass

Returns

boolean

Inherited from

Entity.has

hasTrait()

hasTrait<T>(token): this is LoadingSceneProgressBar & T

Defined in: core/dist/index.d.ts:684

Check if this entity’s class implements a given trait. Acts as a type guard.

Type Parameters

T

T

Parameters

token

TraitToken<T>

Returns

this is LoadingSceneProgressBar & T

Inherited from

Entity.hasTrait

on()

on<T>(token, handler): () => void

Defined in: core/dist/index.d.ts:541

Subscribe to a typed event on this entity. Returns an unsubscribe function.

Type Parameters

T

T

Parameters

token

EventToken<T>

handler

(data) => void

Returns

() => void

Inherited from

Entity.on

onAcquire()?

optional onAcquire(…args): void

Defined in: core/dist/index.d.ts:675

Per-reuse reset, called by EntityPool every time the entity is handed out — including the first time, right after setup(). Its parameters become the pool’s acquire(...) arguments, so a bullet that needs a position and a direction declares onAcquire(x: number, y: number, dir: Vec2).

A pooled class must declare this hook: nothing else resets the state the entity kept while dormant. Declare an empty one if there is genuinely nothing to reset. It runs on a fully active entity, and must be synchronous and non-overloaded — the pool derives acquire’s signature from it, and a set of overloads keeps only the last.

Parameters

args

…unknown[]

Returns

void

Inherited from

Entity.onAcquire

onRelease()?

optional onRelease(): void

Defined in: core/dist/index.d.ts:682

Called by EntityPool when the entity is released, before it goes dormant. Optional even for pooled classes: turning components off is the job of onDisable, so this is for game-level cleanup — dropping a target reference, clearing a listener registered outside setup().

Returns

void

Inherited from

Entity.onRelease

remove()

remove(cls): void

Defined in: core/dist/index.d.ts:537

Remove the component of exactly this class. A base class is not resolved here: remove(Base) does nothing when the entity holds only a subclass, even though has(Base) is true. Remove the concrete class.

Parameters

cls

ComponentClass

Returns

void

Inherited from

Entity.remove

removeChild()

removeChild(name): Entity

Defined in: core/dist/index.d.ts:508

Remove a named child. Returns the detached entity.

Parameters

name

string

Returns

Entity

Inherited from

Entity.removeChild

requireKey()

requireKey(): string

Defined in: core/dist/index.d.ts:691

Return the stable key, or throw if this entity was spawned without one. Use it in the entity’s setup() or in a component’s onAdd() when the code depends on identity (e.g. reading from a createSet keyed by entity key). The spawn call assigns the key before setup() runs.

Returns

string

Inherited from

Entity.requireKey

setActive()

setActive(active): void

Defined in: core/dist/index.d.ts:467

Turn the entity on or off without destroying it. Descendants follow: a child of a dormant entity is dormant whatever its own activeSelf says.

Components whose effective enabled-ness flips get onDisable / onEnable. Per-component enabled flags are left alone, so a component you disabled by hand stays disabled after the entity comes back.

bullet.setActive(false);                    // hidden, updates skipped
bullet.get(Transform).setPosition(x, y);
bullet.setActive(true);                     // back in play, no respawn

An entity with a RigidBodyComponent must be moved through rb.setPosition(x, y) instead — physics owns the transform of a dynamic body and overwrites a direct Transform write on the next frame.

Parameters

active

boolean

Returns

void

Inherited from

Entity.setActive

setup()

setup(opts?): void

Defined in: ui/src/LoadingSceneProgressBar.ts:57

Optional setup method. Called by scene.spawn(Class, params) after the entity is wired to its scene, so components can access services. Override in subclasses — do NOT use the constructor for component setup.

Parameters

opts?

LoadingSceneProgressBarOptions = {}

Returns

void

Overrides

Entity.setup

spawnChild()

Call Signature

spawnChild(name, options?): Entity

Defined in: core/dist/index.d.ts:503

Spawn a new entity in this entity’s scene and add it as a named child. Combines scene.spawn(...) + this.addChild(name, ...) in one call — the idiomatic way to compose entity trees (logical root + visual body

UI sibling + …).

Mirrors the overload shape of Scene.spawn: pass an Entity subclass (with optional setup params), a Blueprint, or omit for an anonymous base Entity.

The parent link is made after the child is built: child.parent is null for the whole of its setup(), including the onAdd() of every component that setup adds, and holds the parent once this call returns. Pass the parent as a setup param when the child needs it. To have setup() read this.parent, reserve both entities in a scene.spawnBatch and call batch.addChild before batch.setup.

this.spawnChild("body", EnemyBody, { color: 0xff6b6b });
this.spawnChild("hp", EnemyHealthBar);

Parameters

name

string

options?

SpawnOptions

Returns

Entity

Inherited from

Entity.spawnChild

Call Signature

spawnChild<E>(name, Class, …rest): E

Defined in: core/dist/index.d.ts:504

UI sibling + …).

Mirrors the overload shape of Scene.spawn: pass an Entity subclass (with optional setup params), a Blueprint, or omit for an anonymous base Entity.

this.spawnChild("body", EnemyBody, { color: 0xff6b6b });
this.spawnChild("hp", EnemyHealthBar);

Type Parameters

E

E extends Entity

Parameters

name

string

Class

() => E

rest

…ClassSpawnArgs<E>

Returns

E

Inherited from

Entity.spawnChild

Call Signature

spawnChild<P>(name, blueprint, params, options?): Entity

Defined in: core/dist/index.d.ts:505

UI sibling + …).

Mirrors the overload shape of Scene.spawn: pass an Entity subclass (with optional setup params), a Blueprint, or omit for an anonymous base Entity.

this.spawnChild("body", EnemyBody, { color: 0xff6b6b });
this.spawnChild("hp", EnemyHealthBar);

Type Parameters

P

P

Parameters

name

string

blueprint

Blueprint<P>

params

P

options?

SpawnOptions

Returns

Entity

Inherited from

Entity.spawnChild

Call Signature

spawnChild(name, blueprint, options?): Entity

Defined in: core/dist/index.d.ts:506

UI sibling + …).

Mirrors the overload shape of Scene.spawn: pass an Entity subclass (with optional setup params), a Blueprint, or omit for an anonymous base Entity.

this.spawnChild("body", EnemyBody, { color: 0xff6b6b });
this.spawnChild("hp", EnemyHealthBar);

Parameters

name

string

blueprint

Blueprint<void>

options?

SpawnOptions

Returns

Entity

Inherited from

Entity.spawnChild

tryGet()

tryGet<C>(cls): C | undefined

Defined in: core/dist/index.d.ts:527

Get a component by class, or undefined if none matches. An exact match wins; otherwise the single component assignable to cls is returned. Throws when several are assignable — use Entity.getAll instead.

Type Parameters

C

C extends Component

Parameters

cls

ComponentClass<C>

Returns

C | undefined

Inherited from

Entity.tryGet

tryGetChild()

tryGetChild(name): Entity | undefined

Defined in: core/dist/index.d.ts:512

Get a child by name, or undefined if not found.

Parameters

name

string

Returns

Entity | undefined

Inherited from

Entity.tryGetChild

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