[whatwg] Features for responsive Web design

[Tab Atkins Jr.]

On Tue, May 15, 2012 at 4:43 PM, Kornel Lesiński <kornel at geekhood.net> wrote:
> On Tue, 15 May 2012 19:25:23 +0100, Matthew Wilcox <mail at matthewwilcox.com>
> wrote:
>
>> I think there's a fundamental mis-match in the mental model of how
>> authors work and what they want. I'm pretty sure we're all shooting
>> for the same "be more efficient" goal, but I think that here on the
>> mailing list that's being approached from an angle that has not
>> considered how authors actually want to do this.
>>
>> We work with designs that re-arrange content and sometimes call for
>> different images of the same semantic meaning. That is *not* the same
>> use case as simply sending a different version of the same image.
>> Srcset only addresses that one type of use, and that is why authors
>> feel it's flawed. It doesn't do what we need, and never can because
>> srcset is based on the assumptin that a UA can somehow pick an
>> appropriate resource to load - when it can't possibly know about the
>> authors use of that resource at that time.
>
>
> There's very good article about the two cases:
>
> http://blog.cloudfour.com/a-framework-for-discussing-responsive-images-solutions/
>
> srcset is not very good for "art-directed" case, while <picture> is perfect
> for it.
>
> <picture> is not very good for resolution/bandwidth optimisation, while
> srcset is perfect for it.
>
>
> I think those are simply two different problems that just happen to be
> called "adaptive images". We should recognized that they're separate and
> design separate solutions for them. A single solution can't do both well,
> since there's a fundamental difference between author-controlled and
> UA-controlled decision.

I suspect this is simply confusion about the proposal - @srcset
handles the "art-directed" case same as <picture>, just with a
somewhat more compact microsyntax rather than using MQs directly.  (On
the plus side, the slightly-special processing of the microsyntax
ensures that at least one image will be chosen no matter what, while
it's unclear how an MQ-based solution will work if none of the MQs
match.)

Given that @srcset was generated as a solution to the use-cases that
the CG brought up, it would be difficult to justify it if it didn't
handle those cases.  ^_^

~TJ