Pointer Grace

Headless Pointer Grace; covers safe triangle, hover intent polygon.


Package	`@vizejs/ui/pointer-grace`
Maturity	stable
Own the source	`vize lib pull pointer-grace`
Requires	—
Aliases	safe triangle, hover bridge, pointer grace
Covers	safe triangle, hover intent polygon

API

`extremeCorners`

Two target corners with the extreme angles from origin.

function extremeCorners(origin: Point, target: Rect): readonly [Point, Point]

`gracePolygon`

Vertices of the origin→target safe triangle plus the target box.

function gracePolygon(origin: Point, target: Rect): readonly Point[]

`pointInGraceArea`

Whether point is inside the target or the safe triangle to it.

function pointInGraceArea(point: Point, origin: Point, target: Rect): boolean

`createPointerGrace`

Create an SSR-safe pointer grace tracker.

function createPointerGrace(options: PointerGraceOptions = {}): PointerGraceController

`usePointerGrace`

Create a pointer-grace tracker disposed with the current Vue effect scope.

function usePointerGrace(options: PointerGraceOptions = {}): PointerGraceController

Behavior

Normative state × input → outcome table for @vizejs/ui/pointer-grace. Every row is exercised by src/families/interaction/pointer-grace/pointer-grace*.test.ts; compile-only assertions live in src/families/interaction/pointer-grace/pointer-grace.types.test-d.ts.

#	State	Input	Outcome	Proven by
G1	idle	origin and target set	polygon is the origin plus extreme target corners	polygon test
G2	armed	pointer inside the target	pending timer is cleared	move inside test
G3	armed	pointer inside the safe triangle	pending timer is cleared	move inside triangle test
G4	tracked	pointer outside polygon	`onGraceEnd` fires after `delay`	leave delay test
G5	pending	dispose	timer is released and further moves throw	dispose test
G6	any	`usePointerGrace` outside a scope	setup diagnostic is thrown	setup test
G7	concurrent SSR	identical trees	byte-identical markup contains no timers	SSR test
G8	public types	invalid delay or mutating readonly refs	compilation rejects misuse	`src/families/interaction/pointer-grace/pointer-grace.types.test-d.ts`