Re: The picture element: complexity

On 12 September 2013 11:52, Simon Pieters <simonp@opera.com> wrote:

> On Thu, 12 Sep 2013 17:45:13 +0200, Reinier Kaper <rp.kaper@gmail.com>
> wrote:
>
>  And there's no way for a browser to detect *if* CSS will be parsed?
>>
>
> Unless CSS has been disabled altogether, it has to assume that there will
> be CSS to be downloaded and parsed.
>

Okay, so no issue here then, correct?


>
>  So you'd end up with two scenarios:
>> 1. No CSS will be parsed on this page, therefore load src[0];
>> 2. CSS *will* be parsed on this page, therefore don't start downloading
>> image resources yet;
>>
>
> The delay in downloading the image is not acceptable.


I'm confused by this. What exactly is unacceptable about this?
I can only imagine that the "delay" you're talking about would be the delay
between the server's response and the actual rendering of the CSS, which is
dependent on the device and connection speed, right?

So if a device is slow in rendering CSS (either a slow device or a poor
connection) how would it benefit from downloading image sources in the
mean-time?

Also, is there any evidence that this is "unacceptable"? As in: use cases
that show websites become unusable / inaccessible because image sources
aren't being downloaded as fast as possible?
Wouldn't the "cost" of a solution like this greatly outweigh any "solution"
where HTML and CSS become tied-in again?

Again I'm sorry if it's my limited knowledge or if this has been passed
before, but it just doesn't seem logical to me that an image source should
be downloaded as fast as possible without looking at any kind of context.


>
>
>    2.1 When CSS parsing takes place: detect which media query is used and
>> load the corresponding src accordingly.
>>
>> The issue here would be when the browser scales up/down, but then
>> alternative resources should be loaded asynchronously and only fully
>> loaded
>> sources should be replacing the previous one.
>>
>> Maybe I just don't have the technical knowledge, but to me it seems this
>> is
>> something that the browser would ideally deal with.
>>
>
> --
> Simon Pieters
> Opera Software
>