Documentation / @ripl/core / Navigator

Class: Navigator

Defined in: packages/core/src/core/navigator.ts:133

An interactive 2D pan/zoom/brush controller — the flat-scene analogue of the 3D Camera. This base class is deliberately context-agnostic: it owns the view model (a { k, x, y } transform plus an optional brush selection) and the imperative commands that mutate it, but it attaches no input listeners of its own. That mirrors the Context/DOMContext split — the DOM-bound DOMNavigator in @ripl/dom extends this class to translate real wheel/pointer/touch gestures into these commands, while non-DOM environments can drive the same view model programmatically (or subclass it with their own input source).

The navigator does not itself repaint; consumers react to the emitted zoom/pan/change/ brush/brushend events (e.g. rescaling axis domains via rescaleDomain, or applying the transform to a context). Translation is unbounded, so a consumer can pan and zoom to content that currently sits outside the viewport — the Figma-style "navigate anywhere" behaviour.

Extends

• EventBus<NavigatorEventMap>

Extended by

• DOMNavigator

Constructors

Constructor

new Navigator(options?): Navigator

Defined in: packages/core/src/core/navigator.ts:145

Parameters

Parameter	Type
options?	NavigatorOptions

Returns

Navigator

Overrides

EventBus.constructor

Properties

Property	Modifier	Type	Default value	Description	Inherited from	Defined in
_brush	protected	NavigatorBrush | null	null	-	-	packages/core/src/core/navigator.ts:141
_scaleExtent	protected	[number, number]	undefined	-	-	packages/core/src/core/navigator.ts:142
_transform	protected	NavigatorTransform	undefined	-	-	packages/core/src/core/navigator.ts:135
_viewport	protected	NavigatorViewport	undefined	-	-	packages/core/src/core/navigator.ts:143
parent?	public	EventBus<NavigatorEventMap>	undefined	The parent event bus that emitted events bubble up to, if any.	EventBus.parent	packages/core/src/core/event-bus.ts:89
defaultKey	readonly	typeof defaultKey	undefined	The key under which resources are retained when no explicit key is provided.	EventBus.defaultKey	packages/core/src/core/disposer.ts:11

Accessors

brush

Get Signature

get brush(): NavigatorBrush | null

Defined in: packages/core/src/core/navigator.ts:163

The current brush selection, or null when nothing is selected.

Returns

NavigatorBrush | null

---

scaleExtent

Get Signature

get scaleExtent(): [number, number]

Defined in: packages/core/src/core/navigator.ts:170

The minimum/maximum zoom factor the transform is clamped to.

Returns

[number, number]

---

transform

Get Signature

get transform(): NavigatorTransform

Defined in: packages/core/src/core/navigator.ts:156

The current view transform (a copy — mutating it does not affect the navigator).

Returns

NavigatorTransform

---

viewport

Get Signature

get viewport(): NavigatorViewport

Defined in: packages/core/src/core/navigator.ts:177

The viewport dimensions used by centerOn/fitBounds.

Returns

NavigatorViewport

Set Signature

set viewport(viewport): void

Defined in: packages/core/src/core/navigator.ts:183

Parameters

Parameter	Type
viewport	NavigatorViewport

Returns

void

Methods

_commit()

protected _commit(event): void

Defined in: packages/core/src/core/navigator.ts:189

Parameters

Parameter	Type
event	"zoom" | "pan"

Returns

void

---

applyPoint()

applyPoint(point): Point

Defined in: packages/core/src/core/navigator.ts:197

Applies the transform to a point in content space, returning its on-screen position.

Parameters

Parameter	Type
point	Point

Returns

Point

---

centerOn()

centerOn(point, viewport?): void

Defined in: packages/core/src/core/navigator.ts:268

Centres a content-space point within the viewport, keeping the current zoom. Useful for bringing an off-screen element into view without changing scale.

Parameters

Parameter	Type
point	Point
viewport	NavigatorViewport

Returns

void

---

clearBrush()

clearBrush(): void

Defined in: packages/core/src/core/navigator.ts:336

Clears the brush selection and emits a brushend event with null.

Returns

void

---

destroy()

destroy(): void

Defined in: packages/core/src/core/event-bus.ts:165

Emits a destroyed event, clears all listeners, and disposes retained resources.

Returns

void

Inherited from

EventBus.destroy

---

dispose()

protected dispose(key?): void

Defined in: packages/core/src/core/disposer.ts:25

Disposes all resources under the given key, or all resources if no key is provided.

Parameters

Parameter	Type
key?	PropertyKey

Returns

void

Inherited from

EventBus.dispose

---

emit()

Call Signature

emit<TEvent>(event): TEvent

Defined in: packages/core/src/core/event-bus.ts:137

Emits an event, invoking all matching handlers and bubbling to the parent if applicable.

Type Parameters

Type Parameter	Default type
TEvent extends Event<undefined>	Event<undefined>

Parameters

Parameter	Type
event	TEvent

Returns

TEvent

Inherited from

EventBus.emit

Call Signature

emit<TEvent>(type, data): Event<NavigatorEventMap[TEvent]>

Defined in: packages/core/src/core/event-bus.ts:138

Emits an event, invoking all matching handlers and bubbling to the parent if applicable.

Type Parameters

Type Parameter
TEvent extends keyof NavigatorEventMap

Parameters

Parameter	Type
type	TEvent
data	NavigatorEventMap[TEvent]

Returns

Event<NavigatorEventMap[TEvent]>

Inherited from

EventBus.emit

---

fitBounds()

fitBounds(bounds, options?): void

Defined in: packages/core/src/core/navigator.ts:285

Zooms and pans so a content-space box fills the viewport (respecting the scale extent and an optional padding). This is the primary way to jump the view to content — including content that currently lies entirely outside the viewport.

Parameters

Parameter	Type
bounds	NavigatorBrush
options?	NavigatorFitOptions

Returns

void

---

has()

has(type): boolean

Defined in: packages/core/src/core/event-bus.ts:94

Returns whether there are any listeners registered for the given event type.

Parameters

Parameter	Type
type	keyof NavigatorEventMap

Returns

boolean

Inherited from

EventBus.has

---

invertPoint()

invertPoint(point): Point

Defined in: packages/core/src/core/navigator.ts:205

Inverts a screen-space point back to content space.

Parameters

Parameter	Type
point	Point

Returns

Point

---

off()

off<TEvent>(type, handler): void

Defined in: packages/core/src/core/event-bus.ts:112

Removes a previously registered handler for the given event type.

Type Parameters

Type Parameter
TEvent extends keyof NavigatorEventMap

Parameters

Parameter	Type
type	TEvent
handler	EventHandler<NavigatorEventMap[TEvent]>

Returns

void

Inherited from

EventBus.off

---

on()

on<TEvent>(type, handler, options?): Disposable

Defined in: packages/core/src/core/event-bus.ts:99

Subscribes a handler to the given event type and returns a disposable for cleanup.

Type Parameters

Type Parameter
TEvent extends keyof NavigatorEventMap

Parameters

Parameter	Type
type	TEvent
handler	EventHandler<NavigatorEventMap[TEvent]>
options?	EventSubscriptionOptions

Returns

Disposable

Inherited from

EventBus.on

---

once()

once<TEvent>(type, handler, options?): Disposable

Defined in: packages/core/src/core/event-bus.ts:127

Subscribes a handler that is automatically removed after it fires once.

Type Parameters

Type Parameter
TEvent extends keyof NavigatorEventMap

Parameters

Parameter	Type
type	TEvent
handler	EventHandler<NavigatorEventMap[TEvent]>
options?	EventSubscriptionOptions

Returns

Disposable

Inherited from

EventBus.once

---

panBy()

panBy(dx, dy): void

Defined in: packages/core/src/core/navigator.ts:224

Pans the view by a pixel delta.

Parameters

Parameter	Type
dx	number
dy	number

Returns

void

---

panTo()

panTo(x, y): void

Defined in: packages/core/src/core/navigator.ts:235

Pans the view to an absolute translation.

Parameters

Parameter	Type
x	number
y	number

Returns

void

---

reset()

reset(): void

Defined in: packages/core/src/core/navigator.ts:313

Resets the transform to the identity (no zoom, no pan).

Returns

void

---

retain()

protected retain(value, key?): void

Defined in: packages/core/src/core/disposer.ts:14

Registers a disposable resource under an optional key for later cleanup.

Parameters

Parameter	Type	Default value
value	Disposable	undefined
key	PropertyKey	Disposer.defaultKey

Returns

void

Inherited from

EventBus.retain

---

setBrush()

setBrush(brush): void

Defined in: packages/core/src/core/navigator.ts:324

Sets the brush selection, normalising the extent, and emits a brush event.

Parameters

Parameter	Type
brush	NavigatorBrush

Returns

void

---

setTransform()

setTransform(transform): void

Defined in: packages/core/src/core/navigator.ts:213

Replaces the view transform outright (clamping k to the scale extent).

Parameters

Parameter	Type
transform	NavigatorTransform

Returns

void

---

zoomBy()

zoomBy(factor, center?): void

Defined in: packages/core/src/core/navigator.ts:246

Multiplies the zoom by factor, keeping center (screen pixels, defaults to the origin) fixed.

Parameters

Parameter	Type
factor	number
center	Point

Returns

void

---

zoomTo()

zoomTo(k, center?): void

Defined in: packages/core/src/core/navigator.ts:260

Sets the absolute zoom factor, keeping center fixed.

Parameters

Parameter	Type
k	number
center	Point

Returns

void