From: Peter Kirk (peterkirk@qaya.org)
Date: Thu Oct 16 2003 - 16:57:33 CST
On 16/10/2003 12:42, Peter Constable wrote:
>>-----Original Message-----
>>From: unicode-bounce@unicode.org [mailto:unicode-bounce@unicode.org]
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>On
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>>Behalf Of Peter Kirk
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>>Thank you. This is the clarification I was looking for, and confirms
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>my
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>>own suspicions. But are there any other views on this? I have heard
>>them from implementers of rendering systems. But I have wondered if
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>this
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>>is because of their reluctance to do the extra work required to
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>conform
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>>to this requirement.
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>This isn't something that can be fixed in rendering systems. It wouldn't
>be hard to do; it's just too much of a performance issue. It has to be
>addressed by the software calling the rendering system.
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>Peter
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>Peter Constable
>Globalization Infrastructure and Font Technologies
>Microsoft Windows Division
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So, you seem to be suggesting that all applications, and the system
libraries which they generally use for character handling, should be
rewritten so that data is transformed into and stored in a particular
well-defined order. Presumably that order would be one of the Unicode
normalisation forms; most likely NFC as that matches the XML
recommendation. Conceivably it could be a different privately defined
form, e.g. based on a different set of combining classes (cf. the
permuted combining class weights of TUS Table 5-6) chosen to get round
some of the well known problems with the standardised combining classes.
Fonts would be required to display correctly only this one clearly
defined order.
It seems to me that this is a viable alternative approach to the
canonical equivalence issue, either globally, or within a particular
company's system architecture provided that there is proper support
within the system libraries and from the system fonts. It might lead to
increased overall efficiency, although with some danger of chaos in the
interim period. It is not the approach which Unicode has recommended in
its implementation guidelines, although I suppose that recommendation
could be changed. I wonder if it is the approach which has been agreed
and will be implemented across the board by any one company. It is
certainly not viable for a rendering group to unilaterally pass to an
applications group, or to a system libraries group, responsibility for
such an important matter ("goes to the core of Unicode") which the
Unicode standard currently clearly states to be a rendering issue.
-- Peter Kirk peter@qaya.org (personal) peterkirk@qaya.org (work) http://www.qaya.org/
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