I think what Ed is saying is that Tai Tham follows a similar model to Myanmar rather than a pure Indic model, where you have a distinct medials vs subjoined consonants wher subjoined consonants require a virama and medials don't Par of a fundamental change between myanar in unicode 4.1 and 5.1 Will look at my sources to confirm for Tai Tham. A. On Thursday, 24 May 2012, Behdad Esfahbod <<a href="mailto:behdad@behdad.org">behdad@behdad.org</a>> wrote: > Hi Thep, > > Humm, the message from Ed hat you are replying to never made it to me or to > the list. Replies inline. > > > On 05/23/2012 06:53 AM, Theppitak Karoonboonyanan wrote: >> Hi, Ed, Behdad, >> >> On Sun, May 20, 2012 at 3:45 AM, Ed Trager <<a href="mailto:ed.trager@gmail.com">ed.trager@gmail.com</a>> wrote: >>> On Fri, May 18, 2012 at 5:48 PM, Behdad Esfahbod <<a href="mailto:behdad@behdad.org">behdad@behdad.org</a>> wrote: >>>> On 05/18/2012 04:02 PM, Ed Trager wrote: >>>>> >>>>> In Tai Tham, U+1A6E VOWEL SIGN E needs to be shifted all the way to >>>>> the left so that the final visual appearance would be: >>>> >>>> Are you sure? Without U+1A60 TAI THAM SIGN SAKOT before the subjoined >>>> consonant? Reading Unicode suggests that you need that sign betwee PA and LA. >>> >>> For most subjoined consonants, yes, that's true. But note in >>> particular that U+1A56 MEDIAL LA and U+1A57 MEDIAL LA TANG LAI were >>> encoded separately. In the case of these two "LA" signs, I believe >>> there are two reasons justifying the separate encoding: >>> >>> (1) These are variant forms of the same subjoined letter LA: >>> apparently, there is no other good way to do it other than encoding >>> both. >>> >>> (2) Both of these LA signs can be part of triple consonant clusters, >>> i.e. "KLW" appears in the common word Thai / Tai word for banana, >>> กล้วย, "klwy" . In Tai Tham, both the L and the W appear as >>> below-base stacked forms (and actually the "y" is also a subjoined >>> form, but it's kind of hanging off the right side of the whole stack). > > I'm not questioning the separate encoding. I don't care :-). What I'm saying > is that you need a SAKOT before them for them to be considered part of the > same syllable according to the Indic OpenType spec and my implementation. > Now, if you think Unicode intended these to subjoin without a SAKOT, then I > like you to point me to documentation about that. > > If that is the case, we would need changes to the Indic machine. Not > impossible, but I first want to make sure that it is indeed the case. > > behdad > > > >>> There are some other separately-encoded subjoining consonant signs: >>> U+1A5B, U+1A5C, U+1A5D, U+1A5E. >> >> Please also count U+1A55 (MEDIAL RA) in the rule, although it's not a >> subjoined form. >> >> Regards, >> -Thep. > _______________________________________________ > HarfBuzz mailing list > <a href="mailto:HarfBuzz@lists.freedesktop.org">HarfBuzz@lists.freedesktop.org</a> > <a href="http://lists.freedesktop.org/mailman/listinfo/harfbuzz">http://lists.freedesktop.org/mailman/listinfo/harfbuzz</a> > -- Andrew Cunningham Senior Project Manager, Research and Development Vicnet State Library of Victoria Australia <a href="mailto:andrewc@vicnet.net.au">andrewc@vicnet.net.au</a> <a href="mailto:lang.support@gmail.com">lang.support@gmail.com</a>