Pointer

Class: Pointer

Defined in: pointer/Pointer.ts:29

A pointer: the fixed mark a ring is read against.

Owns its skin’s view, seats it on the ring, detects the dividers that pass under it each frame (one crossing per divider, however fast the ring turns) and runs the tongue against the ring’s pegs: pushed aside as a peg comes through, carried on its crown, released into a spring. See FlapConfig for the knobs.

Implements#

Disposable

Constructors#

Constructor#

new Pointer(config: PointerConfig, skin: PointerSkin): Pointer;

Defined in: pointer/Pointer.ts:45

Parameters#

Parameter	Type
`config`	`PointerConfig`
`skin`	`PointerSkin`

Returns#

Pointer

Properties#

Property	Modifier	Type	Defined in
`angle`	`readonly`	`number`	pointer/Pointer.ts:31
`facing`	`readonly`	`PointerFacing`	pointer/Pointer.ts:32
`id`	`readonly`	`string`	pointer/Pointer.ts:30
`skin`	`readonly`	`PointerSkin`	pointer/Pointer.ts:35
`tipInset`	`readonly`	`number`	pointer/Pointer.ts:33
`view`	`readonly`	`Container`<`ContainerChild`>	pointer/Pointer.ts:34

Accessors#

deflection#

Get Signature#

get deflection(): number;

Defined in: pointer/Pointer.ts:75

Current flap deflection, degrees.

Returns

number

engagedPeg#

Get Signature#

get engagedPeg(): number | null;

Defined in: pointer/Pointer.ts:80

Index into the ring’s peg angles of the peg carrying the tongue right now, or null.

Returns

number | null

flap#

Get Signature#

get flap(): 
  | Readonly<Required<FlapConfig>>
  | null;

Defined in: pointer/Pointer.ts:85

The flap settings in force, or null for a rigid pointer.

Returns

| Readonly<Required<FlapConfig>> | null

isDestroyed#

Get Signature#

get isDestroyed(): boolean;

Defined in: pointer/Pointer.ts:212

Returns

boolean

Implementation of#

Disposable.isDestroyed

pinRadius#

Get Signature#

get pinRadius(): number;

Defined in: pointer/Pointer.ts:90

Distance from the pin to the hub, px, after layout().

Returns

number

Methods#

contactHalfWidth()#

contactHalfWidth(pegs: ResolvedPegs): number;

Defined in: pointer/Pointer.ts:95

Half the width of the contact zone at the peg ring, px: peg radius plus half the tongue tip.

Parameters#

Parameter	Type
`pegs`	`ResolvedPegs`

Returns#

number

destroy()#

destroy(): void;

Defined in: pointer/Pointer.ts:216

Returns#

void

Implementation of#

Disposable.destroy

layout()#

layout(outerRadius: number, innerRadius: number): void;

Defined in: pointer/Pointer.ts:57

Seat the view on the ring: base rotation and position from the radii.

Parameters#

Parameter	Type
`outerRadius`	`number`
`innerRadius`	`number`

Returns#

void

localAngle()#

localAngle(rotationDeg: number): number;

Defined in: pointer/Pointer.ts:100

The wheel-local angle under this pointer for a disc rotation.

Parameters#

Parameter	Type
`rotationDeg`	`number`

Returns#

number

update()#

update(
   prevRotation: number, 
   rotation: number, 
   dt: number, 
   geometry: RingGeometry, 
   direction: SpinDirection, 
   pegs?: ResolvedPegs | null
): PointerCrossing[];

Defined in: pointer/Pointer.ts:109

Advance one frame. Returns every divider that passed under the pointer between prevRotation and rotation, in the order they passed. pegs drives the tongue; without them a flapping pointer stays at rest.

Parameters#

Parameter	Type	Default value
`prevRotation`	`number`	`undefined`
`rotation`	`number`	`undefined`
`dt`	`number`	`undefined`
`geometry`	`RingGeometry`	`undefined`
`direction`	`SpinDirection`	`undefined`
`pegs`	`ResolvedPegs` \| `null`	`null`

Returns#

PointerCrossing[]