On Tue, 15 May 2012 23:57:48 +0100, Silvia Pfeiffer
<silviapfeiff...@gmail.com> wrote:
Media queries come from the client side. They allow the author of a web
page to tell exactly how she want to lay out her design based on the
different queries. The browser *HAS* to follow these queries. And also,
I don't think (please correct me if wrong) the media query can be subset
to only the stuff that's really meaningful to do at prefetch-time.
The srcset proposal, on the other hand, are purely HINTS to the browser
engine about the resources. They are only declarative hints that can be
leveraged in a secret sauce way (like Bruce said in another mail) to
always optimize image fetching and other features. If you make a new
kind of browser (like e.g. Opera mini) it can have its own heuristics
that make sense *for that single browser* without asking _anyone_.
Without relying on web authors doing the correct thing, or changing
anything or even announce to anyone what they are doing. It's opening up
for innovation, good algorithms and smart uses in the future.
That's the basic difference, totally different. :-)
If that's the case, would it make sense to get rid of the @media
attribute on <source> elements in <video> and replace it with @srcset?
I think something like that would be perfect.
In fact, I'd keep @media, because it serves some cases very well (I see
dpi/bandwidth optimisation as a problem orthogonal to layout adaptation:
http://geekhood.net/MediaQuery-vs-PerfQuery.png)
It may be enough to add another attribute that describes image properties,
and can be used either alone or with conjunction with MQs:
<picture>
<source scale="1" src="low">
<source scale="2" src="high">
</picture>
would be equivalent to:
<img srcset="low 1x, high 2x">
(I've proposed that in the RespImg community group)
And combination of the two opens new possibilities:
<picture>
<source scale="1" src="low-narrow" media="(orientation:portrait)">
<source scale="2" src="high-narrow" media="(orientation:portrait)">
<source scale="1" src="low-wide" media="(orientation:landscape)">
<source scale="2" src="high-wide" media="(orientation:landscape)">
</picture>
--
regards, Kornel Lesiński
