UISurface

Defined in: ui/src/UISurface.ts:27

Mounts a UI tree on an entity: entity.add(new UISurface({...})). Owns the tree’s root UIPanel element (exposed as root) and provides builder methods (.text(), .button(), .panel()) for constructing it. Layout is driven by UILayoutSystem each frame.

Extends

Component

Constructors

Constructor

new UISurface(opts?): UISurface

Defined in: ui/src/UISurface.ts:43

Parameters

opts?

UISurfaceOptions

Returns

UISurface

Overrides

Component.constructor

Properties

_anchor

readonly _anchor: Anchor | undefined

Defined in: ui/src/UISurface.ts:35

Internal

_layer

readonly _layer: string | undefined

Defined in: ui/src/UISurface.ts:37

Internal

_offset

readonly _offset: object

Defined in: ui/src/UISurface.ts:36

Internal

x

x: number

y

y: number

_positioning

readonly _positioning: "anchor" | "transform"

Defined in: ui/src/UISurface.ts:38

Internal

entity

entity: Entity

Defined in: core/dist/index.d.ts:2716

Back-reference to the owning entity. Set by the engine when the component is added to an entity. Do not set manually.

Inherited from

Component.entity

root

readonly root: UIPanel

Defined in: ui/src/UISurface.ts:34

Root element of the mounted UI tree — a UIPanel created with this component and destroyed by it in onDestroy. Same instance for the component’s whole lifetime; after onDestroy it is destroyed (its destroy() is idempotent) and must not be re-added elsewhere.

restorePriority?

static optional restorePriority?: number

Defined in: core/dist/index.d.ts:2874

Snapshot restore order. On load, an entity’s components are re-added in ascending priority, so a component whose onAdd() reads a sibling can rely on lower-priority siblings being present and initialized. Undeclared = 100. Engine components reserve 0-99; game and addon components declare a value only when a sibling onAdd() dependency requires it. Equal priorities restore in save-time add order. Subclasses inherit their base class’s priority unless they declare their own.

Inherited from

Component.restorePriority

updatePriority?

static optional updatePriority?: number

Defined in: core/dist/index.d.ts:2889

Class-level default for updatePriority: every instance runs at this priority unless its own updatePriority is written. Undeclared = 0. Subclasses inherit their base class’s value unless they declare their own. Declare it on a component whose behavior depends on running after (or before) a sibling, so the entity that adds it does not have to control the add order.

class BoundsClamp extends Component {
  static updatePriority = 10; // after the follow that moves the camera
}

Inherited from

Component.updatePriority

Accessors

container

Get Signature

get container(): DisplayContainer

Defined in: ui/src/UISurface.ts:55

The PixiJS Container of the root panel.

Returns

DisplayContainer

context

Get Signature

get context(): EngineContext

Defined in: core/dist/index.d.ts:2770

Access the EngineContext from the entity’s scene. Throws if the entity is not in a scene.

Returns

EngineContext

Inherited from

Component.context

effectiveEnabled

Get Signature

get effectiveEnabled(): boolean

Defined in: core/dist/index.d.ts:2740

Whether the component is actually running: enabled, on an active entity, and past onAdd. This is the state onEnable and onDisable track — read it when a method has to behave one way live and another way dormant.

Returns

boolean

Inherited from

Component.effectiveEnabled

enabled

Get Signature

get enabled(): boolean

Defined in: core/dist/index.d.ts:2732

Whether this component runs. Disabled components are skipped by ComponentUpdateSystem.

Writing this fires onEnable / onDisable when the effective state changes — enabled && entity.isActive. A component disabled here stays disabled through a setActive(false) / setActive(true) cycle on its entity.

Returns

boolean

Set Signature

set enabled(value): void

Defined in: core/dist/index.d.ts:2733

Parameters

value

boolean

Returns

void

Inherited from

Component.enabled

scene

Get Signature

get scene(): Scene

Defined in: core/dist/index.d.ts:2765

Access the entity’s scene. Throws if the entity is not in a scene. Prefer this over threading through this.entity.scene in component code.

Returns

Scene

Inherited from

Component.scene

updatePriority

Get Signature

get updatePriority(): number

Defined in: core/dist/index.d.ts:2758

Where this component runs among its siblings. ComponentUpdateSystem calls update / fixedUpdate on an entity’s components in ascending priority; equal priorities run in add order. Undeclared = 0, so a negative value runs before siblings that keep the default and a positive value runs after them. Writable at any time, before or after add(). Defaults to the class’s static updatePriority.

class Player extends Entity {
  setup() {
    this.add(new Mover());
    this.add(new Brain()).updatePriority = -1; // decides before Mover moves
  }
}

Returns

number

Set Signature

set updatePriority(value): void

Defined in: core/dist/index.d.ts:2759

Parameters

value

number

Returns

void

Inherited from

Component.updatePriority

visible

Get Signature

get visible(): boolean

Defined in: ui/src/UISurface.ts:119

Whether the mounted UI tree is visible. Reads back what you set, even while the entity is dormant and the tree is hidden.

Returns

boolean

Set Signature

set visible(v): void

Defined in: ui/src/UISurface.ts:123

Parameters

v

boolean

Returns

void

Methods

_applyEnabled()

_applyEnabled(effective): void

Defined in: core/dist/index.d.ts:2824

Internal

Force an effective-enabled transition, firing the hook on a flip. Used by Entity for teardown, where enabled and the entity’s activeness both still read true.

Parameters

effective

boolean

Returns

void

Inherited from

Component._applyEnabled

_refreshEnabled()

_refreshEnabled(): void

Defined in: core/dist/index.d.ts:2817

Internal

Recompute effective enabled-ness from enabled and the entity’s activeness, firing the hook on a flip.

Returns

void

Inherited from

Component._refreshEnabled

_runCleanups()

_runCleanups(): void

Defined in: core/dist/index.d.ts:2811

Internal

Run and clear all registered cleanups. Called by Entity.remove() and Entity._performDestroy() before onRemove/onDestroy.

Returns

void

Inherited from

Component._runCleanups

addCleanup()

protected addCleanup(fn): void

Defined in: core/dist/index.d.ts:2805

Parameters

fn

() => void

Returns

void

Inherited from

Component.addCleanup

addElement()

addElement(child): void

Defined in: ui/src/UISurface.ts:98

Append an arbitrary UIElement (e.g. UIImage, UIProgressBar, UICheckbox) as the last child. Prefer the .text(), .button(), and .panel() builders for those element types — they’re shorter.

Parameters

child

UIElement

Returns

void

afterRestore()?

optional afterRestore(data, resolve): void

Defined in: core/dist/index.d.ts:2893

Called after onAdd() during save/load restoration. Apply state that depends on onAdd() having run.

Parameters

data

unknown

resolve

SnapshotResolver

Returns

void

Inherited from

Component.afterRestore

button()

button(label, opts): UIButton

Defined in: ui/src/UISurface.ts:79

Add a button element.

Parameters

label

string

opts

Omit<UIButtonProps, "children">

Returns

UIButton

fixedUpdate()?

optional fixedUpdate(dt): void

Defined in: core/dist/index.d.ts:2863

Called every fixed timestep by the built-in ComponentUpdateSystem.

Parameters

dt

number

Fixed timestep in seconds, scaled by scene and entity timeScale.

Returns

void

Inherited from

Component.fixedUpdate

insertElementBefore()

insertElementBefore(child, before): void

Defined in: ui/src/UISurface.ts:111

Insert child immediately before before in the root panel’s child list. Falls back to append if before isn’t a current child.

Parameters

child

UIElement

before

UIElement

Returns

void

listen()

protected listen<T>(entity, token, handler): void

Defined in: core/dist/index.d.ts:2797

Subscribe to events on any entity, auto-unsubscribe on removal.

Type Parameters

T

T

Parameters

entity

Entity

token

EventToken<T>

handler

(data) => void

Returns

void

Inherited from

Component.listen

listenScene()

protected listenScene<T>(token, handler): void

Defined in: core/dist/index.d.ts:2803

Subscribe to scene-level events, auto-unsubscribe on removal. Handlers fire for bubbled entity events (entity = source) and scene.emit events (entity = undefined).

Type Parameters

T

T

Parameters

token

EventToken<T>

handler

(data, entity?) => void

Returns

void

Inherited from

Component.listenScene

onAdd()

onAdd(): void

Defined in: ui/src/UISurface.ts:136

Called when the component is added to an entity. Validate dependencies here — a service, a sibling component, a render layer — and throw when one is missing. The throw is attributed to this component, recorded in Inspector.getErrors().callbackErrors, and rethrown, so it reaches the caller of entity.add() unchanged.

Returns

void

Overrides

Component.onAdd

onDestroy()

onDestroy(): void

Defined in: ui/src/UISurface.ts:171

Called when the component is destroyed (entity destroyed or component removed).

Returns

void

Overrides

Component.onDestroy

onDisable()

onDisable(): void

Defined in: ui/src/UISurface.ts:132

Called when the component stops being effectively enabled — enabled went false, the entity (or an ancestor) was deactivated, or the component is being removed or destroyed. Put live resources to sleep here; the component is reused afterwards, so do not free anything onEnable cannot rebuild.

Returns

void

Overrides

Component.onDisable

onEnable()

onEnable(): void

Defined in: ui/src/UISurface.ts:128

Called when the component becomes effectively enabled — enabled is true and the entity is active. Fires right after onAdd() for a component added to an active entity, and again on every later flip. Bring live resources back online here (unpause a sound, show a display object, re-enable a physics body). Game-state reset does not belong here: the hook sees whatever state the component held while dormant.

Returns

void

Overrides

Component.onEnable

onRemove()?

optional onRemove(): void

Defined in: core/dist/index.d.ts:2851

Called when the component is removed from an entity.

Returns

void

Inherited from

Component.onRemove

panel()

panel(opts?): UIPanel

Defined in: ui/src/UISurface.ts:84

Add a nested child panel.

Parameters

opts?

UIPanelProps

Returns

UIPanel

removeElement()

removeElement(child): void

Defined in: ui/src/UISurface.ts:103

Remove a previously added element. No-op if the element isn’t a child.

Parameters

child

UIElement

Returns

void

scrollView()

scrollView(opts?): UIScrollView

Defined in: ui/src/UISurface.ts:89

Add a nested scrollable viewport.

Parameters

opts?

UIScrollViewProps

Returns

UIScrollView

serialize()

serialize(): UISurfaceOptions

Defined in: ui/src/UISurface.ts:176

Return a JSON-serializable snapshot of this component’s state. Used by the save system.

Returns

UISurfaceOptions

Overrides

Component.serialize

service()

protected service<T>(key): T

Defined in: core/dist/index.d.ts:2787

Lazy proxy-based service resolution. Can be used at field-declaration time:

readonly input = this.service(InputManagerKey);

The actual resolution is deferred until first property access.

Type Parameters

T

T extends object

Parameters

key

ServiceKey<T>

Returns

T

Inherited from

Component.service

setPointerHandlers()

setPointerHandlers(handlers): void

Defined in: ui/src/UISurface.ts:69

Set the root panel’s pointer / hover handlers (onHover, onPointerOver, onPointerOut) after construction — forwarded to root. (update() can’t double as the prop setter here: on a Component it’s the per-frame lifecycle hook the engine calls.) Like the element update, a present key replaces that handler and an absent key leaves it intact, so a partial setPointerHandlers({ onHover }) won’t drop the others. Handy for wiring attachTooltip: surface.setPointerHandlers({ onHover: tip.setActive }).

Parameters

handlers

PointerEventProps

Returns

void

sibling()

protected sibling<C>(cls): C

Defined in: core/dist/index.d.ts:2795

Lazy proxy-based sibling component resolution. Can be used at field-declaration time:

readonly anim = this.sibling(AnimatedSpriteComponent);

The actual resolution is deferred until first property access.

Type Parameters

C

C extends Component

Parameters

cls

ComponentClass<C>

Returns

C

Inherited from

Component.sibling

text()

text(content, style?): UIText

Defined in: ui/src/UISurface.ts:74

Add a text element.

Parameters

content

string

style?

Partial<TextStyleOptions>

Returns

UIText

update()?

optional update(dt): void

Defined in: core/dist/index.d.ts:2858

Called every frame by the built-in ComponentUpdateSystem.

Parameters

dt

number

Frame delta in seconds, scaled by scene and entity timeScale.

Returns

void

Inherited from

Component.update

use()

protected use<T>(key): T

Defined in: core/dist/index.d.ts:2778

Resolve a service by key, cached after first lookup. Scene-scoped values (registered via scene._registerScoped) take precedence over engine scope. A key declared with scope: "scene" that falls back to engine scope emits a one-shot dev warning — almost always signals a missed beforeEnter hook.

Type Parameters

T

T

Parameters

key

ServiceKey<T>

Returns

T

Inherited from

Component.use

fromSnapshot()

static fromSnapshot(data): UISurface

Defined in: ui/src/UISurface.ts:180

Parameters

data

UISurfaceOptions

Returns

UISurface