Re: [css-writing-modes-3] Writing-mode of alt text and replaced content of textarea, input type="text"

On 03/01/2015 02:31 PM, Gérard Talbot wrote:
> Koji, Elika,
>
> 1- alt text
>
> "
> The content of replaced elements do not rotate due to the writing mode: images, for example, remain upright. However replaced
> content involving text (such as MathML content or form elements) should match the replaced element’s writing mode and line
> orientation if the UA supports such a vertical writing mode for the replaced content.
> "
> http://www.w3.org/TR/css-writing-modes-3/#writing-mode
> http://dev.w3.org/csswg/css-writing-modes-3/#block-flow
>
> I see no normative information regarding the rendering of alt text of images inside a vertical writing-mode. Should I assume
> that alt text should be upright, sideways-right, etc.. when the block inside which the image is has also a correspondent
> text-orientation declaration?

> Eg
>
> http://test.csswg.org/suites/css-writing-modes-3_dev/nightly-unstable/html/replaced-content-image-002.htm
>
> and that test does not require a "should" flag.

The requirements for handling alt text are clearly specified in
   https://html.spec.whatwg.org/multipage/rendering.html#images-2
This means that in most cases, the alt text should be rendered as regular none-replaced inline text.
In some cases it may be rendered as a replaced element containing text,
and that text SHOULD obey the writing mode, as described in CSS3 Writing Modes.

> 2- input text, textarea
>
> "
> The content of replaced elements do not rotate due to the writing mode: images, for example, remain upright. However replaced
> content involving text (such as MathML content or form elements) should match the replaced element’s writing mode and line
> orientation if the UA supports such a vertical writing mode for the replaced content.
> "
> http://www.w3.org/TR/css-writing-modes-3/#writing-mode
> http://dev.w3.org/csswg/css-writing-modes-3/#block-flow
>
> Here, there is a "should". I wonder why it is not a "must" or a "UA are required to" kind of formulation.
>
> The Example 4 (form controls inside a block with vertical-rl writing mode) that follows is not suggesting that this is just
> recommended and not required.

I think it's a SHOULD because form controls are not always
fully under the control of the UA. (They may be under the
control of the OS.) So, in some cases it's not possible or
very difficult for the UA to do anything about this. However,
in most cases it should be possible to perform a graphical
transform at least on the part of the form control that is
embedded into the page, and that will at least allow the
UA to respond to the block direction.

RFC2119 SHOULD is I think adequate in this case. There are
reasons why a UA will not do this. But there have to be
good reasons.

~fantasai

Received on Sunday, 1 March 2015 22:18:27 UTC