Hi, This issue has been bugging devs since 2016.
I'm landing a patch <https://chromium-review.googlesource.com/c/chromium/src/+/4063134> to unprefix -webkit-image-set which will expose the current image-set functionality without needing the '-webkit-' prefix. To address the compat issue, if both prefixed and standard versions are defined in the right order, and the standard version fails parsing, Chrome will fallback to the prefixed version. The `image-set-fallback` test has been added to verify this behavior. Unprefixing image-set fixes 2 of the failing subtests of the image-set-parsing WPT test <https://wpt.fyi/results/css/css-images/image-set/image-set-parsing.html?label=master&label=experimental&aligned&view=subtest&q=image-set-parsing> As a follow up, I will investigate whether we can fix the remaining compat issues. Regards, Traian On Tuesday, August 30, 2016 at 8:51:03 AM UTC-7 dgla...@google.com wrote: > LGTM3 + investigate the syntax issue mentioned by PhistucK. > > :DG< > > > On Monday, August 29, 2016 at 5:06:06 PM UTC-7, Dru Knox wrote: > >> Is this blocked on API owner feedback? >> >> On Mon, Aug 15, 2016 at 1:47 AM PhistucK <phis...@gmail.com> wrote: >> > It has come to my attention in comment 5 >>> <https://bugs.chromium.org/p/chromium/issues/detail?id=630597#c5> that >>> the standard syntax is a superset of the Blink syntax. >>> https://drafts.csswg.org/css-images-3/#image-set-notation >>> >>> Blink supports - >>> background-image: image-set( url("foo.png") 1x, >>> url("foo-2x.png") 2x, >>> url("foo-print.png") 3x ); >>> >>> The standard supports this - >>> background-image: image-set( "foo.png" 1x, >>> url("foo-2x.png") 2x, >>> "foo-print.png" 600dpi ); >>> Basically, you do not need url("..."), you can enter it as a string >>> without the url() function. Also, the resolution part supports more >>> than just #x. >>> >>> I do not have Safari, but according to the unprefixing layout test, it >>> looks like it does not support the standard syntax as well. >>> >>> Should the standard syntax be dropped? Can you talk to WebKit and see if >>> they intend to implement the standard syntax? >>> >>> >>> ☆*PhistucK* >>> >> On Fri, Aug 12, 2016 at 11:47 PM, Chris Harrelson <chri...@chromium.org> >>> wrote: >>> >> LGTM2 >>>> >>>> On Fri, Aug 12, 2016 at 1:11 PM, Philip Jägenstedt <foo...@chromium.org >>>> > wrote: >>>> >>> Easy LGTM1. Given that authors generally assume that prefixed things >>>>> are aliases and that WebKit has made it just so, whatever problems there >>>>> might be with image-set, the only way to move forward is to consider >>>>> -webkit-image-set as part of the compat constraint and navigate >>>>> accordingly. >>>>> >>>>> When it comes to tests, I guess this (like almost all) feature doesn't >>>>> have a shared test suite that we actually use? Nothing in >>>>> https://github.com/w3c/csswg-test/tree/master/css-images-3 and I >>>>> don't know where else it would be? >>>>> >>>>> I suspect that contributing to csswg-tests is, like >>>>> web-platform-tests, not streamlined enough to require it for shipping new >>>>> things, but it would be great if you wanted to take a look at how >>>>> feasible >>>>> it is in this case. Even just a few reftests testing the very basics >>>>> would >>>>> be valuable. >>>>> >>>>> Finally, I wouldn't assume that compat risk is low. When things (like >>>>> the Fullscreen API...) are prefixed only for a very long time, it's >>>>> actually possible that merely unprefixing can break things. Let's hope >>>>> this >>>>> one works out. >>>>> >>>> On Fri, Aug 12, 2016 at 5:59 PM John Mellor <joh...@chromium.org> >>>>> wrote: >>>>> >>>> The CSS image-set spec is old, and has a major todo >>>>>> <https://drafts.csswg.org/css-images-3/#issue-952b7afb>: it only >>>>>> supports variations in screen density (1x, 2x, etc), but doesn't yet >>>>>> allow >>>>>> for selecting images based on viewport width >>>>>> <https://html.spec.whatwg.org/multipage/embedded-content.html#viewport-based-selection> >>>>>> like >>>>>> the more modern <img> srcset+sizes attributes >>>>>> <https://jakearchibald.com/2015/anatomy-of-responsive-images/#varying-size-and-density>. >>>>>> >>>>>> Media queries aren't sufficient for this (though they nicely handle the >>>>>> art >>>>>> direction >>>>>> <https://html.spec.whatwg.org/multipage/embedded-content.html#art-direction> >>>>>> use >>>>>> case, so CSS won't additionally need an equivalent to the <picture> >>>>>> and <source> elements >>>>>> <https://jakearchibald.com/2015/anatomy-of-responsive-images/#varying-width-density-and-art-direction> >>>>>> ). >>>>>> >>>>>> That said, unprefixed image-set is perhaps already a defacto standard >>>>>> (due to websites preemptively unprefixing it, and soon Safari shipping >>>>>> it), >>>>>> so it's likely that when selecting images based on viewport width >>>>>> eventually gets added to CSS images, that will be done by extending the >>>>>> image-set syntax in a backwards compatible way. >>>>>> >>>>> On 8 August 2016 at 08:04, PhistucK <phis...@gmail.com> wrote: >>>>>> >>>>> Edge shows positive signs - >>>>>>> https://developer.microsoft.com/en-us/microsoft-edge/platform/status/cssimageset?filter=f3f0000bf&search=image-set >>>>>>> . >>>>>>> >>>>>> ☆*PhistucK* >>>>>>> >>>>>>> On Mon, Aug 8, 2016 at 8:51 AM, Elliott Sprehn <esp...@chromium.org> >>>>>>> wrote: >>>>>>> >>>>>> Is our implementation compatible with Safari? Is there a test suite? >>>>>>>> >>>>>>> >>>>>>>> On Aug 7, 2016 10:31 PM, "Sunil Ratnu" <sunil...@samsung.com> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> >>>>>>>>> *Contact emails*sunil...@samsung.com >>>>>>>>> >>>>>>>> >>>>>>>>> >>>>>>>>> *Spec* >>>>>>>>> https://drafts.csswg.org/css-images-3/#image-set-notation >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Summary* >>>>>>>>> Support unprefixed version of image-set. >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Motivation* >>>>>>>>> Currently blink implementation is "webkit" prefixed. Given Safari >>>>>>>>> also recently unprefixed image-set, unprefixing can be done without >>>>>>>>> any >>>>>>>>> risk. >>>>>>>>> >>>>>>>>> Link to the WebKit change: >>>>>>>>> https://trac.webkit.org/changeset/202765 >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Interoperability and Compatibility Risk*Low. >>>>>>>>> Firefox and Edge do not support image-set. Only Chrome and Safari >>>>>>>>> support it. Safari also has recently unprefixed -webkit-image-set. >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Ongoing technical constraints*None >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Will this feature be supported on all six Blink platforms >>>>>>>>> (Windows, Mac, Linux, Chrome OS, Android, and Android WebView)?* >>>>>>>>> Yes >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *OWP launch tracking bug* >>>>>>>>> Will be using this as reference bug: >>>>>>>>> https://bugs.chromium.org/p/chromium/issues/detail?id=630597 >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Entry on the feature dashboard* >>>>>>>>> No >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> *Requesting approval to ship?* >>>>>>>>> Yes >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> Thanks & Regards, >>>>>>>>> >>>>>>>>> Sunil >>>>>>>>> >>>>>>>> -- >>>>> >>>> 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+...@chromium.org. >>>>> >>>> >>>> >>> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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