Re: Interaction of "zoom content" and vertical writing modes

Hi Jason,

The current zoom SC in the draft does include the following note:
“320 CSS pixels is equivalent to a starting viewport width of 1280 CSS pixels wide at 400% zoom. For web pages which are designed to scroll horizontally, the 320px should be taken as the height rather than width.”

Talking to Richard Ishida, vertical text is becoming better supported and should become more common.

However, as far as I can tell, horizontally scrolling pages (for vertical text) are still very rare. I’ve found a demo which needed JavaScript to achieve it properly, I don’t think regular browser support is there yet.

Do you think it is worth complicating the SC text to account for horizontally scrolling pages?



Apologies for typos, sent from a mobile.
From: White, Jason J <>
Sent: Tuesday, November 21, 2017 8:35:53 PM
Subject: Interaction of "zoom content" and vertical writing modes

The latest version of the “zoom content” proposal specifies that “content can be presented at a width equivalent to 320 CSS pixels…”. In the case of a vertical writing mode, however, it seems that the proposal would not prevent a user with low vision who enlarges the text within appropriate limits from having to engage in vertical scrolling to read the lines.
I’m not familiar with the details of how vertical scripts are used, but if the whole or a significant portion of a page is presented in such a writing mode, then the current version of “zoom content” doesn’t appear to address the needs of low vision users of such writing systems.
If this issue doesn’t have a straightforward answer, I can open it formally on GitHub.


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Received on Wednesday, 22 November 2017 13:39:37 UTC