@ue-too/board / ZoomControlStateMachine

Class: ZoomControlStateMachine

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:436

State machine controlling zoom input flow and animations.

Remarks

This state machine manages the lifecycle of zoom operations:

User input handling: Accepts or blocks user zoom gestures based on state
Animation control: Manages smooth zoom-to animations
Object tracking: Supports locking camera to follow objects with zoom

State transitions:

ACCEPTING_USER_INPUT → TRANSITION: Start animation (initiateTransition)
ACCEPTING_USER_INPUT → LOCKED_ON_OBJECT: Lock to object (lockedOnObjectZoom...)
TRANSITION → ACCEPTING_USER_INPUT: User input interrupts animation
LOCKED_ON_OBJECT → ACCEPTING_USER_INPUT: User input unlocks

Helper methods simplify event dispatching without memorizing event names.

Example

typescript

const stateMachine = createDefaultZoomControlStateMachine(cameraRig);

// User zooms - accepted in ACCEPTING_USER_INPUT state
const result = stateMachine.notifyZoomByAtInput(1.2, { x: 400, y: 300 });

// Start animation - transitions to TRANSITION state
stateMachine.notifyZoomToAtWorldInput(2.0, { x: 1000, y: 500 });

// User input now may interrupt animation

See

createDefaultZoomControlStateMachine for factory function

Extends

TemplateStateMachine<ZoomEventPayloadMapping, BaseContext, ZoomControlStates, ZoomControlOutputMapping>

Constructors

Constructor

new ZoomControlStateMachine(states, initialState, context): ZoomControlStateMachine

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:442

Parameters

states

Record<ZoomControlStates, State<ZoomEventPayloadMapping, BaseContext, ZoomControlStates, ZoomControlOutputMapping>>

initialState

ZoomControlStates

context

BaseContext

Returns

ZoomControlStateMachine

Overrides

TemplateStateMachine< ZoomEventPayloadMapping, BaseContext, ZoomControlStates, ZoomControlOutputMapping >.constructor

Properties

_context

protected _context: BaseContext

Defined in: packages/being/dist/interface.d.ts:383

Inherited from

TemplateStateMachine._context

_currentState

protected _currentState: ZoomControlStates | "INITIAL" | "TERMINAL"

Defined in: packages/being/dist/interface.d.ts:381

Inherited from

TemplateStateMachine._currentState

_happensCallbacks

protected _happensCallbacks: (args, context) => void[]

Defined in: packages/being/dist/interface.d.ts:386

Parameters

args

["unlock"] | [string, unknown] | ["userZoomByAtInput", ZoomByAtInputPayload] | ["userZoomToAtInput", ZoomToAtInputPayload] | ["transitionZoomByAtInput", ZoomByAtInputPayload] | ["transitionZoomToAtInput", ZoomToAtInputPayload] | ["transitionZoomByAtCenterInput", ZoomByPayload] | ["transitionZoomToAtCenterInput", ZoomToAtInputPayload] | ["transitionZoomToAtWorldInput", ZoomToAtInputPayload] | ["lockedOnObjectZoomByAtInput", ZoomByAtInputPayload] | ["lockedOnObjectZoomToAtInput", ZoomToAtInputPayload] | ["initiateTransition"]

context

BaseContext

Returns

void

Inherited from

TemplateStateMachine._happensCallbacks

_initialState

protected _initialState: ZoomControlStates

Defined in: packages/being/dist/interface.d.ts:388

Inherited from

TemplateStateMachine._initialState

_stateChangeCallbacks

protected _stateChangeCallbacks: StateChangeCallback<ZoomControlStates>[]

Defined in: packages/being/dist/interface.d.ts:385

Inherited from

TemplateStateMachine._stateChangeCallbacks

_states

protected _states: Record<States, State<EventPayloadMapping, Context, States, EventOutputMapping>>

Defined in: packages/being/dist/interface.d.ts:382

Inherited from

TemplateStateMachine._states

_statesArray

protected _statesArray: ZoomControlStates[]

Defined in: packages/being/dist/interface.d.ts:384

Inherited from

TemplateStateMachine._statesArray

_timeouts

protected _timeouts: number | undefined

Defined in: packages/being/dist/interface.d.ts:387

Inherited from

TemplateStateMachine._timeouts

Accessors

currentState

Get Signature

get currentState(): States | "INITIAL" | "TERMINAL"

Defined in: packages/being/dist/interface.d.ts:398

Returns

States | "INITIAL" | "TERMINAL"

Inherited from

TemplateStateMachine.currentState

possibleStates

Get Signature

get possibleStates(): States[]

Defined in: packages/being/dist/interface.d.ts:400

Returns

States[]

Inherited from

TemplateStateMachine.possibleStates

states

Get Signature

get states(): Record<States, State<EventPayloadMapping, Context, States, EventOutputMapping>>

Defined in: packages/being/dist/interface.d.ts:401

Returns

Record<States, State<EventPayloadMapping, Context, States, EventOutputMapping>>

Inherited from

TemplateStateMachine.states

Methods

happens()

Call Signature

happens<K>(...args): EventResult<ZoomControlStates, K extends keyof ZoomControlOutputMapping ? ZoomControlOutputMapping[K<K>] : void>

Defined in: packages/being/dist/interface.d.ts:394

Type Parameters

K

K extends keyof ZoomEventPayloadMapping

Parameters

args

...EventArgs<ZoomEventPayloadMapping, K>

Returns

EventResult<ZoomControlStates, K extends keyof ZoomControlOutputMapping ? ZoomControlOutputMapping[K<K>] : void>

Inherited from

TemplateStateMachine.happens

Call Signature

happens<K>(...args): EventResult<ZoomControlStates, unknown>

Defined in: packages/being/dist/interface.d.ts:395

Type Parameters

K

K extends string

Parameters

args

...EventArgs<ZoomEventPayloadMapping, K>

Returns

EventResult<ZoomControlStates, unknown>

Inherited from

TemplateStateMachine.happens

initateTransition()

initateTransition(): EventResult<ZoomControlStates, void>

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:533

Initiates transition to TRANSITION state.

Returns

EventResult<ZoomControlStates, void>

Remarks

Forces state change to begin animation or transition sequence. Called when starting programmatic camera movements.

notifyZoomByAtInput()

notifyZoomByAtInput(delta, at): EventResult<ZoomControlStates, ZoomControlOutputEvent>

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:468

Notifies the state machine of user zoom input around an anchor point.

Parameters

delta

number

Zoom delta (multiplier)

at

Point

Anchor point for zoom

Returns

EventResult<ZoomControlStates, ZoomControlOutputEvent>

Event handling result with output event

Remarks

Dispatches userZoomByAtInput event. Accepted in ACCEPTING_USER_INPUT and TRANSITION states.

notifyZoomByAtInputAnimation()

notifyZoomByAtInputAnimation(delta, at): EventResult<ZoomControlStates, ZoomControlOutputEvent>

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:485

Initiates a zoom animation around an anchor point.

Parameters

delta

number

Zoom delta (multiplier)

at

Point

Anchor point for zoom

Returns

EventResult<ZoomControlStates, ZoomControlOutputEvent>

Event handling result

Remarks

Dispatches transitionZoomByAtInput event, starting a zoom animation.

notifyZoomToAtCenterInput()

notifyZoomToAtCenterInput(targetZoom, at): EventResult<ZoomControlStates, ZoomControlOutputEvent>

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:502

Initiates a zoom animation to target level around center anchor.

Parameters

targetZoom

number

Target zoom level

at

Point

Anchor point for zoom

Returns

EventResult<ZoomControlStates, ZoomControlOutputEvent>

Event handling result

Remarks

Dispatches transitionZoomToAtCenterInput event for center-anchored zoom animation.

notifyZoomToAtWorldInput()

notifyZoomToAtWorldInput(targetZoom, at): EventResult<ZoomControlStates, ZoomControlOutputEvent>

Defined in: packages/board/src/camera/camera-mux/animation-and-lock/zoom-control-state-machine.ts:519

Initiates a zoom animation to target level around world anchor.

Parameters

targetZoom

number

Target zoom level

at

Point

World anchor point for zoom

Returns

EventResult<ZoomControlStates, ZoomControlOutputEvent>

Event handling result

Remarks

Dispatches transitionZoomToAtWorldInput event for world-anchored zoom animation.

onHappens()

onHappens(callback): void

Defined in: packages/being/dist/interface.d.ts:397

Parameters

callback

(args, context) => void

Returns

void

Inherited from

TemplateStateMachine.onHappens

onStateChange()

onStateChange(callback): void

Defined in: packages/being/dist/interface.d.ts:396

Parameters

callback

StateChangeCallback<ZoomControlStates>

Returns

void

Inherited from

TemplateStateMachine.onStateChange

reset()

reset(): void

Defined in: packages/being/dist/interface.d.ts:390

Returns

void

Inherited from

TemplateStateMachine.reset

setContext()

setContext(context): void

Defined in: packages/being/dist/interface.d.ts:399

Parameters

context

BaseContext

Returns

void

Inherited from

TemplateStateMachine.setContext

start()

start(): void

Defined in: packages/being/dist/interface.d.ts:391

Returns

void

Inherited from

TemplateStateMachine.start

switchTo()

switchTo(state): void

Defined in: packages/being/dist/interface.d.ts:393

Parameters

state

ZoomControlStates | "INITIAL" | "TERMINAL"

Returns

void

Inherited from

TemplateStateMachine.switchTo

wrapup()

wrapup(): void

Defined in: packages/being/dist/interface.d.ts:392

Returns

void

Inherited from

TemplateStateMachine.wrapup

Class: ZoomControlStateMachine ​

Remarks ​

Example ​

See ​

Extends ​

Constructors ​

Constructor ​

Parameters ​

states ​

initialState ​

context ​

Returns ​

Overrides ​

Properties ​

_context ​

Inherited from ​

_currentState ​

Inherited from ​

_happensCallbacks ​

Parameters ​

args ​

context ​

Returns ​

Inherited from ​

_initialState ​

Inherited from ​

_stateChangeCallbacks ​

Inherited from ​

_states ​

Inherited from ​

_statesArray ​

Inherited from ​

_timeouts ​

Inherited from ​

Accessors ​

currentState ​

Get Signature ​

Returns ​

Inherited from ​

possibleStates ​

Get Signature ​

Returns ​

Inherited from ​

states ​

Get Signature ​

Returns ​

Inherited from ​

Methods ​

happens() ​

Call Signature ​

Type Parameters ​

K ​

Parameters ​

args ​

Returns ​

Inherited from ​

Call Signature ​

Type Parameters ​

K ​

Parameters ​

args ​

Returns ​

Inherited from ​

initateTransition() ​

Returns ​

Remarks ​

notifyZoomByAtInput() ​

Parameters ​

delta ​

at ​

Returns ​

Remarks ​

notifyZoomByAtInputAnimation() ​

Parameters ​

delta ​

at ​

Returns ​

Remarks ​

notifyZoomToAtCenterInput() ​

Parameters ​

Class: ZoomControlStateMachine

Remarks

Example

See

Extends

Constructors

Constructor

Parameters

states

initialState

context

Returns

Overrides

Properties

_context

Inherited from

_currentState

Inherited from

_happensCallbacks

Parameters

args

context

Returns

Inherited from

_initialState

Inherited from

_stateChangeCallbacks

Inherited from

_states

Inherited from

_statesArray

Inherited from

_timeouts

Inherited from

Accessors

currentState

Get Signature

Returns

Inherited from

possibleStates

Get Signature

Returns

Inherited from

states

Get Signature

Returns

Inherited from

Methods

happens()

Call Signature

Type Parameters

K

Parameters

args

Returns

Inherited from

Call Signature

Type Parameters

K

Parameters

args

Returns

Inherited from

initateTransition()

Returns

Remarks

notifyZoomByAtInput()

Parameters

delta

at

Returns

Remarks

notifyZoomByAtInputAnimation()

Parameters

delta

at

Returns

Remarks

notifyZoomToAtCenterInput()

Parameters