- From: Florian Rivoal via GitHub <sysbot+gh@w3.org>
- Date: Wed, 16 Jun 2021 00:37:19 +0000
- To: public-css-archive@w3.org
I came to the same observation when reviewing https://github.com/w3c/csswg-drafts/pull/6382. The advance measure of `0`(upon which `ch` is based) is different depending on the writing mode (general case vs vertical upright). This could mean that specified with `ch` font-size-adjust is expect to stretch things by a different amount depending on the writing mode, but that seems unhelpful. As suggested above by @jfkthame we may want to clarify that font-size-adjust with `ch` works on the *width* of the `0` glyph in all writing-mode / text-orientation combination, instead the [advance measure](https://www.w3.org/TR/css-values-4/#length-advance-measure), which is defined to vary based on writing modes. If we do want to be writing-mode sensitive, then `ch` probably should be paired with 2 rather than 1 numbers, the first one relating to the width of `0` and the second one to its height, the later being used in upright vertical contexts, and the first one otherwise. If so, the second one should probably be OK to omit, and when you do so, there should be no adjustment in the corresponding writing mode. The situation is largely the same with the `ic` keyword and the 水 character. It might be less bad in practice if we get it wrong, as `水` is typically square or close to, while `0` is not, so the amount by which things are sized wrong would be less drastic, but it's stiff fundamentally the same issue. -- GitHub Notification of comment by frivoal Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/6288#issuecomment-861923340 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Wednesday, 16 June 2021 00:38:03 UTC