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IntersectionObserverEntry.intersectionRect

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The IntersectionObserverEntry interface's read-only intersectionRect property is a DOMRectReadOnly object which describes the smallest rectangle that contains the entire portion of the target element which is currently visible within the intersection root.

Syntax

var intersectionRect = IntersectionObserverEntry.intersectionRect;

Value

A DOMRectReadOnly which describes the part of the target element that's currently visible within the root's intersection rectangle.

This rectangle is computed by taking the intersection of boundingClientRect with each of the target's ancestors' clip rectangles, with the exception of the intersection root itself.

Example

In this simple example, an intersection callback stores the intersection rectangle for later use by the code that draws the target elements' contents, so that only the visible area is redrawn.

function intersectionCallback(entries) {
  entries.forEach(function(entry) {
    refreshZones.push({
      element: entry.target,
      rect: entry.intersectionRect
    });
  });
}

Specifications

Specification Status Comment
Intersection Observer
The definition of 'IntersectionObserverEntry.intersectionRect' in that specification.
Editor's Draft Initial definition

Browser compatibility

FeatureChromeFirefoxEdgeInternet ExplorerOperaSafari
Basic Support51

53 — 551

55

15(No)??
FeatureAndroidChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic Support5151(Yes)?(No)??

1. From version 53 until version 55 (exclusive): this feature is behind the dom.IntersectionObserver.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.

Document Tags and Contributors

 Contributors to this page: fscholz, Sheppy
 Last updated by: fscholz,