element-by-point

Track the element(s) under a client coordinate.


Package	`@vizejs/composable/element-by-point`
Own the source	`vize lib pull composable:element-by-point`
Runtime exports	`useElementByPoint`
Gzip budget	1536 B

Usage

import { useElementByPoint } from "@vizejs/composable/element-by-point";

Runtime contract

Utility	Category	Stability	SSR	Hydration	Cleanup	Targets	Host globals	Uses
`useElementByPoint`	dom	experimental	deterministic-fallback	stable	reactive-scope	web, desktop	`document`, `window`	`tryOnScopeDispose`

API

`useElementByPoint`

Track the element(s) under a client coordinate. Re-queries whenever x/y change and, with poll, on every animation frame until the owning scope stops. Server renders expose null and an empty list.

function useElementByPoint(options: UseElementByPointOptions): ElementByPointControls

Types

`ElementByPointHost`

Document-like capability used by useElementByPoint.

Member	Type	Description
`elementFromPoint`	`(x: number, y: number) => Element \| null`	Topmost element at a point.
`elementsFromPoint`?	`(x: number, y: number) => Element[]`	Every element at a point, topmost first. Optional: when missing, only the topmost element is reported.

`ElementByPointFrameHost`

Frame scheduler used for continuous polling.

Member	Type	Description
`requestAnimationFrame`	`(callback: FrameRequestCallback) => number`	Schedule a callback before the next repaint.
`cancelAnimationFrame`	`(handle: number) => void`	Cancel a scheduled frame.

`UseElementByPointOptions`

Options for useElementByPoint.

Member	Type	Description
`x`	`MaybeRefOrGetter<number>`	Horizontal client coordinate.
`y`	`MaybeRefOrGetter<number>`	Vertical client coordinate.
`poll`?	`boolean`	Also re-query every animation frame (the element under a fixed point can change when the page scrolls or animates).
`host`?	`MaybeRefOrGetter<ElementByPointHost \| null \| undefined>`	Reactive document capability for alternate runtimes and tests.
`frameHost`?	`MaybeRefOrGetter<ElementByPointFrameHost \| null \| undefined>`	Frame scheduler used when `poll` is enabled.

`ElementByPointControls`

Reactive state returned by useElementByPoint.

Member	Type	Description
`isSupported`	`Readonly<Ref<boolean>>`	Whether a document capability is attached. `false` during server rendering.
`element`	`Readonly<ShallowRef<Element \| null>>`	Topmost element at the point.
`elements`	`Readonly<ShallowRef<readonly Element[]>>`	Every element at the point, topmost first.
`update`	`() => void`	Re-query immediately.