- From: Lionel Wolberger <lionel@userway.org>
- Date: Thu, 18 Aug 2022 17:38:06 +0300
- To: "public-apa-admin@w3.org" <public-apa-admin@w3.org>
- Message-ID: <CAHOHNHcKP+k=CQeM2uNsnc7Zp68PeYq1vQ=ckg45LuXNO=wz0Q@mail.gmail.com>
+1 On Wed, Aug 17, 2022 at 2:40 PM Matthew Atkinson <matkinson@tpgi.com> wrote: > Colleagues: This is a Call for Consensus (CfC) to the Accessible Platform > Architectures (APA) Working Group testing for agreement on a formal comment > on the CSS Color Module Level 5 specification ( > https://www.w3.org/TR/2022/WD-css-color-5-20220628/). > > An accessibility review was requested of the APA as part of our role in > performing horizontal review of W3C documents for accessibility concerns. > > It was reviewed by APA member Matthew who proposed the comments you can > find below. I have made some minor edits for clarity, and to reflect it's a > group comment. Please note that these take into account the discussion we > had about noting trigger warnings in color names, should a specific palette > be used as the basis for creating descriptive color names: > https://www.w3.org/2022/08/10-apa-minutes.html#t10 > > If the group agrees, the main review comment will be posted on the thread > where the review was requested ( > https://github.com/w3c/a11y-request/issues/29) and the rest of the > comments, about the document's accessibility, will be posted on the CSS > Working Group's issue tracker, as a series of separate, specific issues > (which will all be noted as being on the behalf of APA). Non-substantive > edits will be made in order to allow the issues to stand alone. ( > https://github.com/w3c/csswg-drafts/issues/) > > *** Action to Take *** > > This CfC is now open for objection, comment, as well as statements of > support via email. Silence will be interpreted as support, though messages > of support are certainly welcome. > > If you object to this proposed action, or have comments concerning this > proposal, please respond by replying on list to this message no later than > 23:59 (Midnight) Boston Time, Wednesday 24 August. > > NOTE: This Call for Consensus is being conducted in accordance with the > APA Decision Policy published at: > http://www.w3.org/WAI/APA/decision-policy > > <APA Comments> > > # Overall accessibility review comment > > APA has no accessibility concerns regarding the substance of [CSS Color > Module Level 5](https://www.w3.org/TR/2022/WD-css-color-5-20220628/) (we > reviewed the 2022-06-28 WD). > > It's clear that a lot of effort has gone into making the document readable > and understandable. However, we did notice some accessibility barriers, > particularly from the perspective of readers who may struggle with color > perception. These concerns, with suggestions, are being filed as issues on > the CSSWG tracker. > > We're aware that `color-contrast()` has been pushed back to Level 6. > However, we were wondering what are the use cases for this function? The > function selects from a pre-determined list of colours; are there > situations in which the answer could not have been determined at design > time? We don't feel that this function is required in order to further > accessibility, but we're happy to provide any needed support in adding it, > if you wish to add it or something similar in future. > > # Accessibility suggestions on the document's presentation > > ## General: color previews > > ### Naming colors > > Adding "alternative text" to the visual color preview feature could be > very helpful for people with vision impairments who currently have to rely > on the colors' coordinates alone. Whilst coordinates are provided for every > color mentioned in the examples, they may not give the reader much of a > sense of what the color might look like, making the examples hard to follow > (e.g. it's much easier to understand the effects of certain types of mixing > by glancing at the previews and noting the similarities or differences from > the input colors, rather than parsing through the coordinates). The > document describes some of the colors that have previews, but not all. > > There are some tools that gives you the closest color name to a given > (usually hex-encoded) color, from an extensive palette of predefined > colors. This sort of tool would give a good enough idea for most people who > may be unable to perceive the colors directly. The color names could be > generated as part of the document build process, and placed in > visually-hidden text in the document. The text should also indicate if the > colours are transparent. > > One such tool is "color-to-name" (< > https://github.com/stanleyfok/color-to-name>)—however, a small number of > the color names in the palette may be considered vulgar, so they would > either have to be filtered out, or a different tool selected. The same > applies for color names that may be triggering for some people. We can do > more research on tools of this nature, if you like. > > It's noted that out-of-gamut colors are indicated by a red border on their > previews, and they're always described in accompanying text as being out of > gamut, which is helpful. > > ### Keyboard operability for the previews > > The color previews can be hovered with the mouse. When this happens, they > enlarge, covering some of the text behind. This is particularly useful if > the preview is of a transparent color, as the text behind shows through the > preview window. It is not possible to activate the preview with the > keyboard, so keyboard-only users would likely miss out on this helpful > feature. > > ### Previews in `<pre>` blocks—rendering bug > > The previews inside code example blocks can't expand outside of those > blocks, so aren't drawn fully in those cases. > > ## General: Test result indication > > _This is quite possibly a bug in a library you're using, though I couldn't > find any pointers after a brief search relating to WPT._ > > There's a low contrast difference between the two sections of the pie > charts. This is particularly apparent in §4. > > Suggestion: use techniques similar to those from [Figure 21 in the > Understanding WCAG SC 1.4.11 document]( > https://www.w3.org/WAI/WCAG21/Understanding/non-text-contrast.html#figure-passing-pie-chart), > i.e. (1) separating the segments; (2) using more contrasting colours; > and/or (3) using hollow and solid segments to ease differentiation. > > ## §2.2 > > ### Example 2 > > * This example has a figure with a descriptive caption. The `<img>` > element lacks an `alt` attribute. The `alt` text should mention that the > image shows three colours (the two inputs, and the mixed output) on a plane > with two axes. The axes are labelled "a" and "b" and cross at the origin, > which is in the centre of the plot. We are looking down the L axis onto an > ab plane. > * An `<img>` that has `alt` text in Example 22 (in §3.6) refers to this > plane as the CH plane. This seems to be conventional, but it may be helpful > for people who are not familiar with color spaces to mention it in the > document's text. > * For someone who struggles to see the color, or low-contrast colors, it > would be helpful to label the colors on the chart ("peru", "palegoldenrod" > and "mixed" for the mixed color, in this case). (You could perhaps do this > with numbers, to save space, and keep the layout simple, in the diagram, as > long as they match up to numbers, color previews, and coordinates in the > text below.) > > ### Example 3 > > The above three issues apply here too. > > ## §3.6 > > ### Example 22 > > In the spirit of the issue reported above, we don't feel this needs > extensive `alt` text (though describing the axes and general situation > would be helpful). However, it would be particularly helpful to ensure that > the different colors can be identified on the plot, e.g. via labelling. > > ## §4.4 > > ### Figure 5 > > * The `<img>` needs `alt` text such as "A color swatch, in a grid layout". > * The second part is marked up as a `<table>` but doesn't seem to be one > semantically (it's just placing the text to match the layout of the color > swatch above). Suggest applying `role="presentation"` to the table, to > remove the tabular structure semantics (or you could re-code it using > `<div>`s and `<span>`s). That would have the effect of linearizing the > table from a screen reader perspective, but that would likely be less > confusing than encountering a "table" without headers. > > ### Example 33 > > Color previews are missing. > > ## §5 > > ### Figure 6 > > * The `<img>` needs an `alt` attribute that explains this is a color > swatch in a grid formation (as per figure 5) but that circles are imposed > on each grid square. The `<figcaption>` does a great job of explaining the > rest. > * As with figure 5, this table should have the table semantics removed (or > be re-coded using `<div>`s and `<span>`s). > > </APA Comments> > > -- > Matthew Tylee Atkinson (he/him) > -- > Principal Accessibility Engineer > TPG Interactive > https://www.tpgi.com > A Vispero Company > https://www.vispero.com > -- > This message is intended to be confidential and may be legally privileged. > It is intended solely for the addressee. If you are not the intended > recipient, please delete this message from your system and notify us > immediately. > Any disclosure, copying, distribution or action taken or omitted to be > taken by an unintended recipient in reliance on this message is prohibited > and may be unlawful. > >
Received on Thursday, 18 August 2022 14:38:55 UTC