[css3-writing-modes] text-orientation:upright

I have a concern about text-orientation:upright.

[CSSWG] Minutes and Resolutions 2012-08-15 Wed PM II: Writing Modes, ...
   - RESOLVED: text-orientation:upright is a forced upright; it always means upright
               (because UTR50 does not define SVO anymore)

First, I was surprised at this. Brackets and dashes with “forced upright” will be useless.

Second, I have a question. Is it true “forced upright; it always means upright”?

The current draft of CSS3 Writing Modes says: “Upright characters in ‘mixed-right’ and ‘upright’ modes are typeset with vertical font metrics. … Additionally, font features (such as alternate glyphs) intended for use in vertical typesetting must be used. (E.g. the OpenType ‘vert’ feature must be enabled.) ”

This means that if we have fonts that have rotated vertical glyphs for brackets and dashes, they are rendered nicely even with “forced upright”. If so, we should not call it “forced upright”, rather we should call it “font-dependent upright”.

My concern here is that the actual orientation will be font dependent and that causes serious problem when we set ‘text-orientation: upright’ for arrows (←↑→↓↖↗↘↙ etc.) and pointing indexes (☜☝☞☟ etc.). These characters are rotated (MVO=R) in default ‘text-orientation: mixed-right’ and we will often want to set upright for these characters (e.g. for “⇧UP”). If fonts do not have rotated vertical glyphs we will get the expected results, but unfortunately most CJK fonts have rotated vertical glyphs for some arrows, and it is font-dependent which arrows are rotated.

I think the ‘text-orientation’ property should be useful to control the orientation of characters in vertical text, and it is very unfortunate if it cannot use for characters that the orientation is most important, arrows and pointing indexes. Should we recommend to use the ‘text-combine-horizontal’ property instead of ‘text-orientation’?

In my opinion, the best solution is to use the SVO data for ‘text-orientation: upright’ and to disable rotated vertical glyphs for SVO=U characters.

Best regards,

Shinyu Murakami
Antenna House

Received on Saturday, 15 September 2012 07:15:37 UTC