Re: Adapting Text Units: Spaces, paragraphs, and ems

Hi Stephen and Lisa,

Steve, thank you very much for your explanation and work on this. I
agree that the paragraph bullet complicate testing Adapting Text SC.

On 7/12/17, Repsher, Stephen J <stephen.j.repsher@boeing.com> wrote:

> The other 3 bullets are important because they affect the content within the
> element and thus how it is sized is being tested.  What is being tested with
> paragraph spacing?

Lisa, could you please answer that, as you're the person who is
objecting to having the Adapting Text SC in 2.1 without it.

Steve, my thought would be the same as WCAG 2.0 1.4.8 Visual
Presentation: spacing between paragraphs. It says:

"...Line spacing (leading) is at least space-and-a-half within
paragraphs, and paragraph spacing is at least 1.5 times larger than
the line spacing..."

http://www.w3.org/TR/WCAG20#visual-audio-contrast-visual-presentation

Is that untestable?

COGA does have their Visual Presentation SC #51:
https://github.com/w3c/wcag21/issues/51

If it would simplify matters, perhaps it could be specified in Issue
51. Lisa your thoughts. Would you object to that?

Thanks again.

Kindest Regards,
Laura

On 7/12/17, Repsher, Stephen J <stephen.j.repsher@boeing.com> wrote:
> If paragraph spacing must be included, then we can do it as a factor on font
> size just like the rest, although it will have ambiguity as to which
> “paragraph’s” font size to use along with much more…
>
> I purposely did not include it because of all the other layout questions it
> raises, and the fact that we’d need a clear definition for paragraph
> spacing.  I’m sorry but it’s just nowhere near as testable as the other 3
> bullets.  Here’s some questions we should be prepared to deal with:
>
> 1.       Which paragraph’s font size do I base the spacing on?
>
> 2.       Is it spacing before or after or split between the two?
>
> 3.       Does a heading or sub-heading count as a paragraph?  Seems like
> that would be a much bigger distinguisher so I’m assuming no.
>
> 4.       What if a list, block quote, image, or other element breaks up a
> paragraph?  This becomes an important difference depending on the answers to
> 1 and 2.
>
> 5.       If a paragraph has another visual distinction like a first line
> indent or border, is the spacing requirement the same?
>
> In the end though, I’m having a tough time seeing how a test for paragraph
> spacing could ever really fail in the context of this criterion, and what
> CSS rules would be used to test it that didn’t make a lot of assumptions on
> tags used by the author.  For example, if I start with a typical site with
> no negative margins and no absolutely positioned elements, then what
> possible content or functionality could be lost by applying:
>
> p + p {margin-top: 1em}
> p ~ p {margin-bottom: 1em}
>
> The other 3 bullets are important because they affect the content within the
> element and thus how it is sized is being tested.  What is being tested with
> paragraph spacing?
>
> Steve
>
>
> From: Katie Haritos-Shea [mailto:ryladog@gmail.com]
> Sent: Wednesday, July 12, 2017 2:23 PM
> To: Laura Carlson <laura.lee.carlson@gmail.com>
> Cc: John Foliot <john.foliot@deque.com>; public-low-vision-a11y-tf
> <public-low-vision-a11y-tf@w3.org>; Jason White <jjwhite@ets.org>;
> w3c-wai-gl@w3.org; Alastair Campbell <acampbell@nomensa.com>; Detlev Fischer
> <detlev.fischer@testkreis.de>; Repsher, Stephen J
> <stephen.j.repsher@boeing.com>; Greg Lowney <gcl-0039@access-research.org>
> Subject: Re: Adapting Text Units: Spaces, paragraphs, and ems
>
> +1 to Stephens technology agnostic language approach.
>
> Awesome work Wayne, Alistair, Laura etc all...
> Katie Haritos-Shea
> 703-371-5545
>
> On Jul 12, 2017 2:11 PM, "Laura Carlson"
> <laura.lee.carlson@gmail.com<mailto:laura.lee.carlson@gmail.com>> wrote:
> Hi Steve,
>
> How would you propose to phase new paragraph bullet using font size?
> Lisa has objected to inclusion of the Adapting Text SC in 2.1 without
> it.
>
> Thanks.
>
> Kindest Regards,
> Laura
>
> On 7/12/17, Repsher, Stephen J
> <stephen.j.repsher@boeing.com<mailto:stephen.j.repsher@boeing.com>> wrote:
>> We’re not being technology agnostic here.  The truth is that the only
>> reason
>> we are drawing a difference between em units and a unitless factor on the
>> font size is technology-specific to CSS.  In reality they are exactly the
>> same, i.e. for the current element:
>>
>> `Line-height: 1.5` = `line-height: 1.5em`
>>
>> The problem is that these are inherited properties, so a length value in
>> em
>> passes the same computed length to children, while the factor becomes a
>> factor on the child’s font size.  Obviously the latter is usually the
>> desired behavior.  Why the CSS standard doesn’t also allow factors to be
>> used for `letter-spacing` and `word-spacing` is a good question.
>>
>> So, to be totally technology agnostic here, we ought to pick one and be
>> consistent.  Given the confusion that could arise by specifying
>> inheritance
>> with em units, I’d strongly vote for the following:
>>
>>
>> 1.       line height (line spacing) to at least 1.5 times the font size
>>
>> 2.       letter spacing (tracking) to at least 0.12 times the font size
>>
>> 3.       word spacing to at least 0.16 times the font size
>>
>> We can explain what this translates to for CSS in Understanding, which is
>> advantageous in case things change.
>>
>> Steve
>>
>> From: Alastair Campbell
>> [mailto:acampbell@nomensa.com<mailto:acampbell@nomensa.com>]
>> Sent: Wednesday, July 12, 2017 12:17 PM
>> To: John Foliot <john.foliot@deque.com<mailto:john.foliot@deque.com>>
>> Cc: Laura Carlson
>> <laura.lee.carlson@gmail.com<mailto:laura.lee.carlson@gmail.com>>; Greg
>> Lowney
>> <gcl-0039@access-research.org<mailto:gcl-0039@access-research.org>>; Jason
>> White <jjwhite@ets.org<mailto:jjwhite@ets.org>>; Detlev
>> Fischer <detlev.fischer@testkreis.de<mailto:detlev.fischer@testkreis.de>>;
>> w3c-wai-gl@w3.org<mailto:w3c-wai-gl@w3.org>;
>> public-low-vision-a11y-tf
>> <public-low-vision-a11y-tf@w3.org<mailto:public-low-vision-a11y-tf@w3.org>>
>> Subject: Re: Adapting Text Units: Spaces, paragraphs, and ems
>>
>> That’s fine for me, thanks.
>>
>> Any objections? Going, going…
>>
>> -Alastair
>>
>>
>> From: John Foliot
>>
>> Hi Alastair,
>>
>> A bit more fine-tuning... how about:
>>
>> * line-height (spacing) to at least 1.5 em (space line-and-a-half)
>> * spacing between paragraphs to at least 2 em (2 lines)
>>
>> * letter spacing (tracking) to at least 0.12 em
>> * word spacing to at least 0.16 em
>>
>> ???
>>
>> JF

-- 
Laura L. Carlson

Received on Wednesday, 12 July 2017 19:59:07 UTC