LGTM1 On Wed, Mar 5, 2025 at 6:38 AM Stephen Chenney <schen...@chromium.org> wrote:
> Thanks Vlad. Answers inline. > > On Tue, Mar 4, 2025 at 10:34 PM Vladimir Levin <vmp...@chromium.org> > wrote: > >> >> >> On Tuesday, March 4, 2025 at 11:17:42 AM UTC-5 Chromestatus wrote: >> >> Contact emails schen...@chromium.org >> >> Explainer https://github.com/whatwg/html/pull/10873 >> >> Specification https://github.com/whatwg/html/pull/10873 >> >> Summary >> >> The <canvas> DOM element, like all DOM elements, accepts a `lang` >> attribute that is used to define language specific treatment for font >> selection (when fonts have locale specific glyphs). Browsers respect this >> attribute. However, when an OffscreenCanvas is created there is no way to >> set locale information, possibly resulting in a state where an offscreen >> canvas produces rendered results that differ from the canvas in which it's >> output is used. This feature adds a `lang` IDL attribute to >> CanvasTextDrawingStyles to give developers direct control over the language >> for the text drawing and metrics. >> >> >> Blink component Blink>Canvas >> <https://issues.chromium.org/issues?q=customfield1222907:%22Blink%3ECanvas%22> >> >> TAG review None >> >> TAG review status Not applicable >> >> >> Is there a reason for no TAG review? I'm not sure if there's an exception >> that applies here. >> > > I didn't consider TAG review because the discussion in WHATWG viewed this > as fixing an oversite in the canvas spec, and from a technical/ergonomics > perspective it seems pretty straight forward. Happy to see if the TAG have > any opinions though so I'll file an issue. > > >> >> Risks >> >> >> Interoperability and Compatibility >> >> None >> >> >> *Gecko*: No signal (https://github.com/mozilla/ >> standards-positions/issues/1150) Non official support in WHATWG >> meetings. >> >> *WebKit*: Support (https://github.com/WebKit/ >> standards-positions/issues/439) >> >> *Web developers*: No signals >> >> >> Although this seems like a small feature, having no web developer signals >> is a bit unfortunate. Do you know of any cases where this behavior is >> currently broken and would be fixed by the change? >> > > Finding reports of developers having problems is a bit tricky, in part > because "canvas" is also a very widely used online learning framework with > lots of people who care about language. Anyways, this is one report of > offscreen canvas giving the wrong metrics > <https://forum.nwoods.com/t/html-lang-set-to-ja-or-zh-the-text-will-exceed-the-frame/16450> > for text due to the lack of offscreen language support (exactly what this > intent is expected to fix). Hitting the problem of offscreen/DOM > inconsistency that we are trying to fix here would require a localized > application using a common font for multiple locales with > developers/users attentive enough to notice problems and report them. > > Another way of looking at Web Developer signals is that this is a > prerequisite spec addition for the highly demanded Extended Text Metrics > feature set. Without this we don't get better canvas text in general. > > >> >> >> >> *Other signals*: >> >> 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? >> >> Pure addition of functionality. >> >> >> Debuggability >> >> None >> >> >> Will this feature be supported on all six Blink platforms (Windows, Mac, >> Linux, ChromeOS, Android, and Android WebView)? Yes >> >> Feature is useful on all platforms and important for localization. >> >> >> 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/html/canvas/element/manual/text? >> label=master&label=experimental canvas.2d.lang.dynamic.html >> canvas.2d.lang.empty.canvas.html canvas.2d.lang.inherit.canvas.html >> canvas.2d.lang.inherit.disconnected.canvas.html canvas.2d.lang.inherit. >> document.disconnected.canvas.html canvas.2d.lang.inherit.document.html >> canvas.2d.lang.html https://wpt.fyi/results/html/ >> canvas/offscreen/manual/text?label=master&label=experimental >> canvas.2d.offscreen.lang.inherit.html canvas.2d.offscreen.lang.html >> canvas.2d.offscreen.transferred.lang.inherit.document.html >> canvas.2d.offscreen.transferred.lang.inherit.html >> canvas.2d.offscreen.transferred.lang.html >> canvas.2d.offscreen.worker.lang.inherit.html >> canvas.2d.offscreen.worker.lang.html >> https://wpt.fyi/results/html/canvas/element/text?label= >> master&label=experimental 2d.text.lang.default.html >> 2d.text.lang.valid.html https://wpt.fyi/results/html/ >> canvas/offscreen/text?label=master&label=experimental >> 2d.text.lang.default.html 2d.text.lang.valid.html >> >> >> Flag name on about://flags Experimental Web Platform Features >> >> Finch feature name CanvasTextLang >> >> Non-finch justification >> >> This is a feature addition with very very little expected impact on >> performance or changes in existing website functionality. >> >> >> Requires code in //chrome? False >> >> Tracking bug https://issues.chromium.org/issues/385006131 >> >> Availability expectation WebKit implementation is moving forward. There >> is agreement that the feature is needed and implementation is not complex. >> I would anticipate all browsers have implemented within 2 years. >> >> Adoption expectation I would expect that the feature is adopted by >> default, in that the default value for the new attribute is likely to be by >> far the most common. So sites will immediately "adopt" the feature and get >> the benefits without taking any action. >> >> >> It wasn't immediately clear: what's the default value that would be used? >> > > Default is "inherit", the behavior of which matches DOM canvas right now, > and would make offscreen canvas match DOM canvas. > > >> >> >> Adoption plan The feature is publicized at https://blogs.igalia.com/ >> schenney/canvas-localization-support/ and will have an MDN page. >> >> Non-OSS dependencies >> >> Does the feature depend on any code or APIs outside the Chromium open >> source repository and its open-source dependencies to function? >> None. >> >> Sample links >> https://blogs.igalia.com/schenney/canvas-localization-support >> >> Estimated milestones Shipping on desktop 136 DevTrial on desktop 135 Shipping >> on Android 136 DevTrial on Android 135 Shipping on WebView 136 >> >> 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. >> >> Link to entry on the Chrome Platform Status https://chromestatus.com/ >> feature/5066778773028864?gate=5145440662847488 >> >> Links to previous Intent discussions Intent to Prototype: >> https://groups.google.com/a/chromium.org/g/blink-dev/c/WEjhPwI6lLc >> >> >> 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 blink-dev+unsubscr...@chromium.org. > To view this discussion visit > https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGsbWzSYuQJfmu_MWGOCOOWufKqk6zH1miOqJ_B6E%3DOx9-2RnA%40mail.gmail.com > <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/CAGsbWzSYuQJfmu_MWGOCOOWufKqk6zH1miOqJ_B6E%3DOx9-2RnA%40mail.gmail.com?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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