W3C home > Mailing lists > Public > public-i18n-core@w3.org > October to December 2008

RE: [1.2T-LC] i18n comment 8: Text rendering order

From: Martin Duerst <duerst@it.aoyama.ac.jp>
Date: Fri, 31 Oct 2008 11:07:30 +0900
Message-Id: <6.0.0.20.2.20081031104901.16381d88@localhost>
To: "Richard Ishida" <ishida@w3.org>, "'Chris Lilley'" <chris@w3.org>, <www-svg@w3.org>
Cc: <public-i18n-core@w3.org>

Hello Richard,

I can't speak for Chris, but I think for the word 'hindi', that's
what the text would mean. Also, depending on the design of the
glyphs, and on how many glyph variants are available (e.g. for
the short 'i' to deal with different left-from-stem width of the
logically preceeding consonant), there may not be any overlap in
this case.

Also, while the text deals with one character being associated with
several glyphs, it doesn't talk about the situation where several
characters are associated with one glyph, which would be typical
for Indian ligatures. There may also be cases where relationships
are more complicated, e.g. a ligature glyph for a first consonant
and a vowel and a separate glyph for a second consonant between
the first consonant and the vowel, and so on.

Regards,   Martin.

At 03:45 08/10/31, Richard Ishida wrote:
>
>Hi Chris,
>
>I'm pursuing this thread because I know you want to get this stuff wrapped
>up.  However, I haven't seen any further correspondence on this topic, and
>I'm not sure what the result of the comment is, nor what the impact is on
>rendering of what you're describing. 
>
>I don't know whether this helps or hinders: If you had the word 'hindi'
>written in hindi (see the example at
>http://rishida.net/scripts/tutorial/slides/Slide0670.html), would that mean
>that you render the 'h' first, then the 'i' to its left, then the 'n'
>diacritic, then the 'd' and finally the 'ii' vowel sign. (I'm assuming here
>that differences/overlap, etc are applied on a character by character basis,
>however, three of these characters are combining characters, and there are
>two grapheme clusters involved, and I don't know how that plays into this.
>
>Cheers,
>RI
>
>============
>Richard Ishida
>Internationalization Lead
>W3C (World Wide Web Consortium)
>
>http://www.w3.org/International/
>http://rishida.net/
>
>
>
>> -----Original Message-----
>> From: public-i18n-core-request@w3.org
>[mailto:public-i18n-core-request@w3.org]
>> On Behalf Of Chris Lilley
>> Sent: 13 October 2008 18:55
>> To: www-svg@w3.org; public-i18n-core@w3.org
>> Subject: Re: [1.2T-LC] i18n comment 8: Text rendering order
>> 
>> 
>> Hello www-svg,
>> 
>> 
>> > "The glyphs associated with the characters within text content block
>> > elements are rendered in the logical order of the characters in the
>> > original document, independent of any re-ordering necessary to
>> > implement bidirectionality. Thus, for text that goes right-to-left
>> > visually, the glyphs associated with the rightmost character are
>> > rendered before the glyphs associated with the other characters"
>> 
>> This is my own viewpoint and has not yet been discussed with the WG.
>> 
>> Good catch about other reasons for reordering besides bidi. I agree
>> the current text suggests its the only reason for reordering. Would
>> this text be better?
>> 
>>   "The glyphs associated with the characters within text content block
>>   elements are rendered in the logical order of the characters in the
>>   original document, independent of any re-ordering necessary for
>>   visual display (e.g., to implement bidirectionality). Thus, for text
>>   that goes right-to-left visually, the glyphs associated with the
>>   rightmost character are rendered before the glyphs associated with
>>   the other characters, as they come earlier in logical order."
>> 
>> The reason we need to describe rendering order is to cover the case
>> where glyphs overlap, have different colours, and use transparency. In
>> that case, the rendering order affects the visual result.
>> 
>> 
>> --
>>  Chris Lilley                    mailto:chris@w3.org
>>  Technical Director, Interaction Domain
>>  W3C Graphics Activity Lead
>>  Co-Chair, W3C Hypertext CG


#-#-#  Martin J. Du"rst, Assoc. Professor, Aoyama Gakuin University
#-#-#  http://www.sw.it.aoyama.ac.jp       mailto:duerst@it.aoyama.ac.jp     
Received on Friday, 31 October 2008 02:14:19 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Friday, 31 October 2008 02:14:20 GMT