Re: Shaping characters in upright orientation in vertical text flow

I am not an Arabic expert, but what I seem to remember is as follows:

a) Arabic letters oriented upright should be in isolated shape

b) This is a very unseemly sight for an Arabic reader and authors should 
avoid this mode of presentation. Arabic letters rotated 90 degrees 
counterclockwise so that the text is read from top to bottom while the 
letters can be connected is a much better option.

Shalom (Regards),  Mati
       Bidi Architect
       Globalization Center Of Competency - Bidirectional Scripts
       IBM Israel
       Mobile: +972 52 2554160




From:   Koji Ishii <kojiishi@gluesoft.co.jp>
To:     "public-i18n-bidi@w3.org" <public-i18n-bidi@w3.org>
Cc:     "'WWW International' (www-international@w3.org)" 
<www-international@w3.org>, John Daggett <jdaggett@mozilla.com>
Date:   17/01/2012 06:26
Subject:        Shaping characters in upright orientation in vertical text 
flow



Hello, I've got an item that I need your help.

CSS Writing Modes Level 3 has the "text-orientation" property[1]. With 
that, you can set glyph orientation in vertical text flow.

The issue is about how to render shaping characters when 
"text-orientation: upright" is applied. Please scroll down the spec a 
little bit to see "Figure 12. 'text-orientation' values"; "upright" is the 
one I'm talking about. You see all characters including Latin are upright 
in this style.

How do you expect shaping characters look in this case?

Currently, the spec states "Shaping characters from such scripts are 
shaped in their isolated forms." This is primarily from fantasai's 
investigations.

Another source to support this behavior is how Excel renders its vertical 
text flow[2].

There're other options such as "always keep them sideways (i.e., rotated 
by 90 degrees.)" This is the behavior usually done by using 
"text-orientation: sideways-right"[1] (see Figure 12 for examples,) but I 
understand there're some scripts that can never be written in upright and 
therefore renders the same way as "sideways-right" even when author 
applied "upright".

I personally have no idea which one is the right behavior here.

John Daggett in his recent mail pointed out that[3]:
> For 'upright' the spec currently states "Shaping characters from
> such scripts are shaped in their isolated forms." This means that
> 'upright' applied to Arabic in vertical text would break the shaping.
> I'm really not sure that this is the right behavior, I think this 
behavior
> is why Microsoft was talking about making an alternate proposal for
> UTR50.

Could anyone give us your opinions on this? Thank you for your support in 
advance.

[1] http://dev.w3.org/csswg/css3-writing-modes/#text-orientation
[2] 
http://lists.w3.org/Archives/Public/www-archive/2012Jan/att-0010/upright-excel.png

[3] http://lists.w3.org/Archives/Public/www-style/2012Jan/0655.html

Regards,
Koji

Received on Tuesday, 17 January 2012 08:26:04 UTC