- From: Sam Weinig via GitHub <noreply@w3.org>
- Date: Tue, 28 Apr 2026 18:57:52 +0000
- To: public-css-archive@w3.org
weinig has just created a new issue for https://github.com/w3c/csswg-drafts:
== [scroll-animations] How/when does the "inset" parameter in the ViewTimeline constructor get evaluated? ==
How/when does the [`inset`](https://drafts.csswg.org/scroll-animations/#dom-viewtimelineoptions-inset) property on [ViewTimelineOptions](https://drafts.csswg.org/scroll-animations/#dictdef-viewtimelineoptions), and processed in the [ViewTimeline constructor](https://drafts.csswg.org/scroll-animations/#dom-viewtimeline-viewtimeline), get evaluated.
Specifically, the spec says "If a [DOMString](https://webidl.spec.whatwg.org/#idl-DOMString) value is provided as an inset, parse it as a [<'view-timeline-inset'>](https://drafts.csswg.org/scroll-animations/#propdef-view-timeline-inset) value". But it doesn't say how that [<'view-timeline-inset'>](https://drafts.csswg.org/scroll-animations/#propdef-view-timeline-inset) value is then resolved. (This applies to the sequence of [CSSNumericValue](https://drafts.css-houdini.org/css-typed-om-1/#cssnumericvalue) form as well).
For example, how/when should an inset value like `{ inset: "1em 2em" }` be resolved? In the CSS form, using `view-timeline-inset: 1em 2em;`, it is resolved at computed value time, which is well defined. This extends beyond just font sizes, for example, consider the use of something like sibling-index(), `{ inset: "calc(1px * sibling-index()) 2px" }`?
Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/13852 using your GitHub account
--
Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Tuesday, 28 April 2026 18:57:52 UTC