Re: Proposing content-hidden for background-image and img content

On Tue, Aug 30, 2011 at 12:03 PM, Charles Pritchard <chuck@jumis.com> wrote:
> On 8/18/11 7:08 PM, Tab Atkins Jr. wrote:
>> On Thu, Aug 18, 2011 at 6:14 PM, Charles Pritchard<chuck@jumis.com>
>>  wrote:
>>> Proposing content-hidden for background-image and img content.
>>>
>>> I'd like to see a new option: "visibility: content-hidden", such as,
>>> <img style="visibility: content-hidden; background: blue" />
>>>
>>> Like visibility, the content is not rendered, but, background and border
>>> fills are.
>>> A lot of work has gone into background-* paint services.
>>>
>>>
>
> ...
>>
>> I assume the use-case you're trying to hit is that you want an<img>
>> element in your source (for semantics, @alt, etc.), but the actual
>> image content could be generated by a CSS<image>  value.
>>
>> In this case, the solution will be (once I or Elika pick up the
>> Generated Content spec in the near future) just providing the image
>> you want to the 'content' property (likely with some keyword that
>> indicates it should still be treated as a replaced element; details
>> are still vague).
>>
>
> I want to keep the content, just not in the render tree. Sure, content:
> hidden; would be an alternative.
>
> css generated content is a big spec, and a big undertaking. My thinking, and
> it could be wrong, is that visibility: content-hidden
> could/would be implemented much sooner than content: hidden. The rendering
> block is already -mostly- developed in the browsers, for visibility: hidden.
>
> The code around css generated content is quite a bit more complex and i'm
> concerned about the quantity of possible of side effects. Given that it does
> not do any content generation, visibility: content-hidden is simpler for
> vendors to pick up. In doing so, they can exploit a good deal of that power
> that CSS <image> values have gained.

Relying on background-image and hidden content prevents you from doing
certain useful things as well, like auto-sizing the element to the
size of the element.

The rendering of "content: url(foo.jpg) replaced;" is also already
mostly in the browsers, so that's not a strong concern.

~TJ

Received on Tuesday, 30 August 2011 20:18:06 UTC