Re: [smc-devel] Re: Malayalam OpenType font (GPLed)

[Baiju M]

> In this case this means that MALAYALAM VOWEL SIGN AU U+0D4C is _defined_
> so that it can be represented in text with the codepoint U+0D4C, or as a
> sequence of the codepoints of MALAYALAM VOWEL SIGN E U+0D46 and
> MALAYALAM AU LENGTH MARK U+0D57. Both of these representations should be
> treated the same way in every aspect of data processing.
>
> Now, the Unicode Consortium apparently didn't know the situation in the
> Malayalam community well enough, and allocated the codepoints in a way
> which you find erroneous. They made a mistake, as they have
> done also a few times before, which is very unfortunate.

I think they are going to make another big mistake if they are accepting
the proposal to include Malayalam chillu as basic characters by govt. of
India (http://tdil.mit.gov.in/tdil-april-2002.pdf)

I explained the deatails at post to unicode discussion list.

http://groups.yahoo.com/group/unicode/message/15818
http://groups.yahoo.com/group/unicode/message/15819

>
>> OpenType has single substitution feature. cannt I use that,
>> even if Yudit split it into both sides?
>
> No, because as it is, it is a _requirement_ of the Unicode standard to
> split the codepoint U+0D4C to two sides in display. Every
> Unicode compliant program should do so now and in the future, too, since
> this won't be changed even if an official proposal was made.

Now we have to confirm it from unicode consortium.

>> But single substitution is not working in Yudit, I tested raghu.ttf
>> (Devanagari) font , there is some single substitution for
>> vowel sign I (U093F), its not working, may be a bug.
>
> I'm not sure what you mean by this. For me, raghu.ttf is working
> just fine, and Yudit is placing the vowel sign I to the left of the
> consonant cluster it is attached to, as it should.

The cluster should be substituted by looking at the context (Lookup Type 6
of GSUB, Chaining Contextual Substitution)
for example :
<RA [U+0D90]> + <U+093F>
<KA [U+0915]> + <U+093F>
<KA [U+0915]> + <virama [U+094D]> + <KA [U+0915]> + <U+093F>

These three should be displayed differently (in raghu.ttf)
I think one more is there.

Just try this in GEdit (A simple editor in GNOME 2), then you can see
the differense.

Regards,
Baiju M