- From: bryan rasmussen <rasmussen.bryan@gmail.com>
- Date: Thu, 5 Dec 2024 17:44:25 +0100
- To: Steve Green <steve.green@testpartners.co.uk>
- Cc: Marc Haunschild <marc.haunschild@accessibility.consulting>, WAI Interest Group discussion list <w3c-wai-ig@w3.org>
- Message-ID: <CAHKsR6_+R04yFG5_QmQmFQwAs=-C54RxuJE586x_pXEpJRZG7A@mail.gmail.com>
I would think it's not tailwind's problem but a side effect of how clamp works, that said we can say that the min and max font size will be 16 and 20px respectively, depending on the viewport size,so I would think naively that you test 1. if the viewport is a size where it will be the min size, can iI zoom in 200% and get increase of double font size? 2- do the same for the max font size 20px 3. choose one point in between those and test and if it increases then it passes? Since assumption being that the scaling of page will be even in a range between the min and max? I have probably not thought this through, but if I take a text on a page and change it to be font-fize: clamp(16px, 50vh, 20px); then it is of course always going to be 20px at 100%, and it scales correctly, and if I do font-fize: clamp(16px, .01vh, 20px); then it is 16px at 100% and it scales correctly, it's really only that part in the middle that is difficult to reason about when the values are more useful that those above - but if one point in the middle matches to what is specified and scales correctly I would think the assumption would be the rest does - as long as there isn't a variable anywhere in that middle expression all that previous was only in reference to clamp however, not in reference to transform scale or zoom which are too headachy for me to consider at this time of day. Thanks, Bryan Rasmussen On Thu, Dec 5, 2024 at 4:44 PM Steve Green <steve.green@testpartners.co.uk> wrote: > I hope to do the bookmarklet during the Christmas break. I will make it > available, but it will be VERY expensive! > > > > Steve > > > > *From:* Marc Haunschild <marc.haunschild@accessibility.consulting> > *Sent:* 05 December 2024 15:32 > *To:* Steve Green <steve.green@testpartners.co.uk> > *Cc:* WAI Interest Group discussion list <w3c-wai-ig@w3.org> > *Subject:* Re: Testing practice for > > > > Hi Steve, > > > > That's exactly the problem. As tailwind becomes more and more popular, > this problem becomes more common. > > > > And yes - different parts of pages do behave differently some grow, some > don#t - im the EU it also makes testing EN clause 11.7. user preferences > more difficult - from browser to browser the results vary. It’s really a > problem. > > > > If you will be able to develop a bookmarklet to make testing easier, that > would be very helpful! > > > > And yes, I wasn’t#t even thinking of transform()! > > > > Thanks for your answer! > > > > Marc > > > > > > Am 05.12.2024 um 16:18 schrieb Steve Green <steve.green@testpartners.co.uk > >: > > > > We were discussing this on the W3C GitHub a couple of days ago, and it’s > more complex than you might imagine. > > https://github.com/w3c/wcag/issues/4157 > > > > At the time I was testing a website that set the font size in a similar > way to yours, which means the base font size is different at every viewport > width and hence at every browser zoom level. > > > > Until that discussion, I had been viewing the computed base font size in > the DOM Inspector, then increasing the browser zoom until the product of > the new base font size and the zoom level was at least twice the original > base font size. It’s a real pain to do that because in principle you need > to do it for each different piece of text because they may not scale by the > same proportion (or at all, as was the case with some text on my website). > > > > And then it got worse. It turns out that the CSS “zoom” and > “transform:scale()” properties change the rendered font size without > changing the computed base font size, so you have to check their values at > 100% zoom and at subsequent levels (in case they change) and factor that > into the previous calculation. > > > > I am working on a bookmarklet that will do the calculations for all the > text on a page, so you can see what has changed size and by how much at > each zoom level. Unfortunately, there’s no way to just measure the rendered > font height, so I am hoping there are no other CSS properties or other > weird technologies (anyone remember SIFR?) that might affect the rendered > font size. > > > > Steve Green > > Managing Director > > Test Partners Ltd > > > > *From:* Marc Haunschild <marc.haunschild@accessibility.consulting> > *Sent:* 05 December 2024 13:51 > *To:* WAI Interest Group discussion list <w3c-wai-ig@w3.org> > *Subject:* Testing practice for > > > > Hi all, > > > > > Does anybody has a suggestion how to test 1.4.4 Resize Text when the > font-size is defined by something like this (extracted from a tailwind css > project): > > > > > .text-copy-md { > font-size:clamp(16px,calc(16px + (20 - 16) * ((100vw - 1024px) / (1920 - > 1024))),20px); > } > > > > Is there maybe a browser plugin that shows me when I resized the text up > to 200% of the original size? > > > > -- > Mit freundlichen Grüßen > > Marc Haunschild - he / him - #gernPerDu > Qualifizierte und autorisierte Prüfstelle im BIK-BITV-Prüfverbund > > Marc Haunschild Accessibility Consulting > Sonnenhof 32 > 53119 Bonn > > Telefon: 0170 8 64 00 63 > Web: https://Accessibility.Consulting <https://accessibility.consulting/> > https://haunschild.de > Email: Marc.Haunschild@Accessibility.Consulting > > >
Received on Thursday, 5 December 2024 16:44:40 UTC