cyrezdev / a11y-apca-sass Goto Github PK

Hi Cyril @cyrezdev

First, WOW. What a project this is, It is impressive, one of the best iterations of an APCA based library I've seen, possibly the best——I have not exercised it as yet, but have gone through the code, and all the basics look very good. I am not familiar with sass, so I might be missing unique features you might have going on.

There are a few minor bits that need to be addressed before a public release IMO, and I appreciate you asking for review.

ALSO, just as an FYI, before this repo goes public, I may want to delete this issue thread, as it may contain privileged IP at times.

Documentation

1) Careful with WCAG 3 mentions

On the main README, it is okay to say "APCA is the candidate for WCAG 3".

However, this line:

Level | Accessibility level as defined by APCA-W3 and WCAG 3: Bronze (minimum), Silver, Gold (higher).

We can not say "Accessibility level as defined by APCA-W3 and WCAG 3". We can say "Accessibility level as defined by APC-RC".

Nothing is defined in WCAG 3 at the moment, and therefore no reference can be made to WCAG 3 or W3C in terms of conformance until we are at the draft recommendation stage. But that is why IRT and APC-RC... but also, APC-RC is not at a stage of "conformance yet". I might be more comfortable with "Objectives to meet" sort of language, but this is not critical.

2) ARC is changing

I am going to change APCA Readability Criterion to something that does not spell ARC, as an accessibility company already has a product called ARC now. Up in the air as to what, but APC-RC will do for the time being.

Documentation AND code

3) Polarity, non-polar, and absolute Lc

This caught my attention:

Absolute (non-polar) Lc value

I'm sorry Cyril, as you had no way of knowing, but there is a non-polar mode and I'm afraid this is not it.

This can be called "absolute Lc" or something that does not refer to polarity, but not non-polar please, as there are some specific definitions for the non-polar version, and how it will be used.

Because it is woven all through your code, I am more than happy to adjust and issue a pull request for this.

Related question

It looks to me that throughout the code, the "Lnp" variable is being used often — but I didn't see how polarity was being checked or enforced? It's fine to use the absolute for connecting to a lookup table for instance, but does need to be tokenized in some way to ensure correct BoW/WoB.

While this may seem less important today, there are other color spaces where this will become very important.

Before I do anything, I'll wait to hear from you in terms of how you are handling polarity, particulary for Silver level.

4) x-height marks the spot...

Regarding font-size: what is actually important is xheight. Does sass have any utilities for using/finding xheight?

5) Backwards Scope

Again, here is something that you didn't know about because it is not public facing yet.

There will be one low level that is:

• Non-polar mode only (authorized non polar, not abs(Lc))
• Covers the same text and non-text scope as WCAG 2.2
• Lc 75 = 4.5:1 and Lc 60 = 3:1
• Non-text and very large text may get an Lc 15 break (down to Lc 45) for darker colors (if both darker than #c0c0c0 possibly), TBD.

This is the bassackwards compatible level.

Maybe call it the "Brass" level? Or maybe Iron, LOL (link to my general article on "metal rules", absolutely nothing at all to do with accessibility).

Bronze Scope

At the moment, scope for BRONZE is going to be "primary content and elements required to use/nav the site". But not non-polar.

Note: the maximum contrast ONLY applies to reverse (negative) Lc values, I.e. -90 or -85. It does not apply to light mode.

Covered: placeholders that are labels, nav icons, captions unless only a byline or covered in main content. Data viz needed for understanding (chart lines, pie pieces)

Not covered: placeholders that are NOT labels when a form label does exist, disabled controls, copyright, corp logos, ancillary, dataviz not needed for understanding (grid lines, alternating chart row highlighting) and anything not covered by WCAG 2.2.

As always this is interim.

Silver, Gold

You're gold man! amazing job over all, sorry about the errata above, I can help if you like. Seems to me the biggest deal is around the non-polar issue? Renaming to Lcat (Lc absolute) maybe?? I don't want to muck up any of your logic or workflow...

For the real non-polar, I don't want to release the actual non-polar mode yet for a variety of reasons. But just FYI, the actual non polar mode does not have a text/bg field, it has hi/lo fields, and the low field is always processed as if it was text, the high field is always bg (even if it is actually being used for text). The hi/lo of course is tested and inverted if needed, so a user can put whatever anywhere, and it acts like the webaim checker.

Nonpolar is only for the backwards compat mode.

Please feel free to hit me up with questions comments etc.

Thank you for reading... and for all your great work!