RE: AGWG Meeting, Wed November 15

Thanks Alastair.
I like your version well enough and your explanations are thorough.
I agree that your essential exception is covers logotypes and sensory experiences.
My only remaining comment then is editorial, that we should be consistent with the formatting of SC from 2.0.   Since your rewrite now has just one list and not two, that is much easier!  If I am correct to think that the exception really only applies to Graphical Objects and not Controls, here is a version that keeps the exception inline:
1.4.11 Graphics Contrast:  The visual presentation of non-text content has a contrast ratio of at least 3:1 against adjacent color(s) for each of the following:  (Level AA)

  *   Controls:  Focus indicators, and visual information used to indicate state for active user interface components;
  *   Graphical Objects:  Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.

From: Alastair Campbell [mailto:acampbell@nomensa.com]
Sent: Tuesday, November 14, 2017 6:05 PM
To: Bailey, Bruce <Bailey@Access-Board.gov>; WCAG <w3c-wai-gl@w3.org>; Joshue O Connor <josh@interaccess.ie>; Repsher, Stephen J <stephen.j.repsher@boeing.com>
Subject: RE: AGWG Meeting, Wed November 15

Hi Bruce,

Based on previous comments that we worked around, I can see a few issues:

  *   It would need to be the "visual indicators of user interface components", otherwise the button/input itself must have contrast (I'm not actually sure what bit within a control would need the contrast?).
  *   'Provided' doesn't cover the same scope as 'required for understanding', and without that graphics/icons with text next to them would be in scope (and shouldn't be). There isn't a concept in WCAG 2.0 for what we need here.
  *   We have some examples of things I don't think fit into the exceptions and need an 'essential' exception: Gradient graphs (like heat maps) where the colour is mapped to a scale and smoothly transitions. Also, medical tests / diagrams where it has to be certain colours to match reality, and screenshots where changing it would then not represent the thing you've copied.
Note that I had also started with 1.4.3 & 1.1.1 exceptions (possibly at your suggestion?) and then iterated to what we had pre-TPAC.

I also went over the comments and came to this version, leaning more on the essential exception and assuming lots of examples in the understanding:

The visual presentation of non-text content has a contrast ratio of at least 3:1 against adjacent color(s) for each of the following

- Controls: Focus indicators, and visual information used to indicate state for active user interface components
- Graphical objects: Parts of graphics required to understand the content

Except when a particular presentation of the graphic is essential to the information being conveyed.

Cheers,

-Alastair

From: Bailey, Bruce

I do not expect to make the call tomorrow.  I took a stab at 1.4.11 and put it into the discussion tab on the wiki page for the comment summary on 1.4.11.
http://www.w3.org/WAI/GL/wiki/Talk:Comment_Summary_1-4-11

I closely tracked 1.4.3, substituting "non-text content" for "text and images of text" and added the Sensory exception from 1.1.1.  I used only terms and phrasing that are already in 2.0.  The "provided for understanding and operating" comes from 1.3.3.

Here it is below:

1.4.11 Graphics Contrast:  The visual presentation of focus indicators, user interface components, and parts of non-text content provided for understanding and operating the Web page have a contrast ratio of 3:1, except for the following:  (Level AA)

  *   Incidental: Inactive user interface components, or those that are not visible to anyone, have no contrast requirement;
  *   Logotypes: Non-text content that is part of a logo or brand name has no minimum contrast requirement;
  *   Sensory: Non-text content that is primarily intended to create a specific sensory experience has no minimum contrast requirement.