[csswg-drafts] [css-writing-modes] Clarify value direction for elements "progress" and "meter" with vertical writing mode (#7929)

dizhang168 has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-writing-modes] Clarify value direction for elements "progress" and "meter" with vertical writing mode ==
Currently, elements "progress" and "meter" don't have well defined behavior when they have the style `writing-mode: vertical-lr` or `writing-mode: vertical-rl`. For example, Firefox is the only vendor to support vertical writing-mode for these elements. Here is what a progress bar looks like:
```HTML
<progress value="70" min="0" max="100" style="writing-mode: vertical-lr"> 70% </progress>
``` 
<img width="17" alt="image" src="https://user-images.githubusercontent.com/18745440/197030258-c265dff5-a174-47fd-979e-5f31cabc3651.png">
Question 1: 
Should the value part (blue color) of the element be rendered from top down (as reading is normally done from top to bottom) or should it be rendered bottom to top (so it looks like a glassware that gets filled up)?

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Further, currently for the horizontal mode, we are able to change the direction of the progress bar from left-to-right to right-to-left.
```HTML
<progress value="70" min="0" max="100" style="direction: rtl"> 70% </progress>
<progress value="70" min="0" max="100" style="direction: ltr"> 70% </progress>
```
<img width="332" alt="image" src="https://user-images.githubusercontent.com/18745440/197031649-93eeea50-a41a-42e4-a234-dd9f2f165d27.png">
However, there are no direction for ttb `top-to-bottom` or `bottom-to-top` (not that I am aware of at least).
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Question 2:
Should there be a way to allow changing direction for the vertical writing modes?

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Spec link:
https://drafts.csswg.org/css-writing-modes-4/#block-flow
https://drafts.csswg.org/css-writing-modes/#direction

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/7929 using your GitHub account


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Received on Thursday, 20 October 2022 18:48:59 UTC