LGTM2 On Wednesday, November 19, 2025 at 8:24:20 AM UTC-8 Chris Harrelson wrote:
> LGTM1 > > On Thu, Nov 13, 2025 at 9:25 PM Rik Cabanier <[email protected]> wrote: > >> Thanks Alex! I'm excited to see this shipped in Chrome. >> >> This feature is currently behind an experimental flag in the Meta Quest >> Browser because the underlying OpenXR API has a bug that will be fixed in >> the next version of our OS. >> Once that goes out, we will remove the experimental flag and I'll work on >> adding support in three.js. >> >> On Fri, Nov 14, 2025 at 8:25 AM Chromestatus < >> [email protected]> wrote: >> >>> *Contact emails* >>> [email protected] >>> >>> *Specification* >>> >>> https://immersive-web.github.io/webxr/#xrvisibilitymaskchangeevent-interface >>> >>> >>> *Summary* >>> Adds an XRVisibilityMaskChange event that will provide a list of >>> vertices and a list of indices to represent the mesh of the visible portion >>> of the user's viewport. This data can then be used to confidently limit the >>> amount of the viewport drawn to in order to improve performance. To better >>> support this event, XRView's are also given unique identifiers to allow >>> easier pairing with the associated masks. This is an extension to the core >>> WebXR specification. >>> >>> *Blink component* >>> Blink>WebXR >>> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3EWebXR%22> >>> >>> *Web Feature ID* >>> webxr-device <https://webstatus.dev/features/webxr-device> >>> >>> *Motivation* >>> Without this change, pages are forced to draw to the full texture >>> provided for the corresponding viewport, when portions of this viewport >>> will not even be visible to the user, resulting in wasted work. By >>> providing an event to describe the clipped-to area of the viewport, >>> developers can save on per-frame work, and improve performance of their >>> experiences, by reducing the required fill rate by 5-10% depending on >>> device. This is given as an event because some system-level functionality >>> may in fact capture the entire viewport, and thus those systems would like >>> to toggle between having developers draw the entire viewport versus only >>> the area visible to the active user. >>> >>> *Initial public proposal* >>> *No information provided* >>> >>> *TAG review* >>> *No information provided* >>> >>> *TAG review status* >>> Not applicable >>> >>> *Risks* >>> >>> >>> *Interoperability and Compatibility* >>> *No information provided* >>> >>> *Gecko*: Positive ( >>> https://github.com/mozilla/standards-positions/issues/218) >>> >> > Note: is is for the WebXR device API generally, not for this addition. > > >> >>> *WebKit*: No signal ( >>> https://github.com/WebKit/standards-positions/issues/155) Note that the >>> Apple Vision Pro does ship WebXR behind a flag. >>> >>> *Web developers*: Positive Note that Meta has a pending change to merge >>> into one of the popular WebXR libraries pending this shipping in other >>> browsers. >>> >>> *Other signals*: The feature was proposed by Meta, who I believe has >>> this implemented in the Quest browser. >>> >>> *Ergonomics* >>> This is an event that is fired with a typically smallish amount of data, >>> but also expected to only be triggered infrequently. The feature itself is >>> designed to help developers improve performance of their experiences by >>> reducing needless work. >>> >>> *Activation* >>> The structure of the event is designed to cleanly work with clipping >>> logic within glsl, and developers from Meta already have draft changes to >>> merge into THREE.js, a popular WebXR library to take advantage of this. >>> >>> *Security* >>> N/a >>> >>> *WebView application risks* >>> >>> Does this intent deprecate or change behavior of existing APIs, such >>> that it has potentially high risk for Android WebView-based applications? >>> Feature is not exposed on WebView >>> >>> >>> *Debuggability* >>> *No information provided* >>> >>> *Will this feature be supported on all six Blink platforms (Windows, >>> Mac, Linux, ChromeOS, Android, and Android WebView)?* >>> No >>> WebXR is not supported on WebView. Sessions are really only possible on >>> Windows and Android, but types are not blocked on other Desktop platforms. >>> >>> *Is this feature fully tested by web-platform-tests >>> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md>?* >>> Yes >>> https://wpt.fyi/results/webxr?label=experimental&label=master&aligned >>> Note that tests *do* run on the CQ. Results on wpt.fyi are blocked by >>> crbug.com/410607164 >>> >>> *Flag name on about://flags* >>> *No information provided* >>> >>> *Finch feature name* >>> WebXRVisibilityMask >>> >>> *Rollout plan* >>> Will ship enabled for all users >>> >>> *Requires code in //chrome?* >>> False >>> >>> *Tracking bug* >>> https://issues.chromium.org/issues/450538226 >>> >>> *Availability expectation* >>> Feature should be available on Meta Quest browser either now or soon. >>> >>> *Estimated milestones* >>> Shipping on desktop 144 >>> Shipping on Android 144 >>> >>> *Anticipated spec changes* >>> >>> Open questions about a feature may be a source of future web compat or >>> interop issues. Please list open issues (e.g. links to known github issues >>> in the project for the feature specification) whose resolution may >>> introduce web compat/interop risk (e.g., changing to naming or structure of >>> the API in a non-backward-compatible way). >>> None expected >>> >>> *Link to entry on the Chrome Platform Status* >>> https://chromestatus.com/feature/5073760055066624?gate=6599862548299776 >>> >>> This intent message was generated by Chrome Platform Status >>> <https://chromestatus.com>. >>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "blink-dev" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected]. >>> To view this discussion visit >>> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69166702.050a0220.b6611.00a2.GAE%40google.com >>> >>> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/69166702.050a0220.b6611.00a2.GAE%40google.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> You received this message because you are subscribed to the Google Groups >> "blink-dev" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> > To view this discussion visit >> https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGN7qDAqivD%2BX0g_HdexXTEbhMwvNc93rJMM696k%3DouHEKvNVA%40mail.gmail.com >> >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGN7qDAqivD%2BX0g_HdexXTEbhMwvNc93rJMM696k%3DouHEKvNVA%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/a/chromium.org/d/msgid/blink-dev/fac20a12-5e85-482f-b9e8-bf3770291a8bn%40chromium.org.
