> On 4 Apr 2017, at 23:51,Richard Wordingham <[email protected]> > wrote: > > On Tue, 4 Apr 2017 09:39:57 +0700 > "Gerriet M. Denkmann" <[email protected]> wrote: > >> So the rule should be: >> >> A consonant may have zero or one tone/other marks and also zero or >> one top/bottom vowels. Exceptions: >> NIKHAHIT + tone mark (no top/bottom vowel) >> MAITAIKHU + tone mark (no top/bottom vowel) > > This list is not exhaustive.
> The order of MAITAIKHU and tone mark is significant - it should affect > rendering. Most fonts disagree (exception: Tahoma and Microsoft Sans Serif). Are there minority languages where the order has really a semantic meaning? Could one create a list of all possible combinations of non-spacing marks for Thai, minority languages and languages written using Thai characters (e.g. Pali, Sanskrit, Khmer, Burmese, etc.)? Including cases, where the order of these marks has a semantical meaning. The next step would then to agree on rules of normalisation. For use in domain names, there probably need to be additional rules. This is not what I am concerned with. The normalisation has (almost ?) nothing to do with the question of fonts. E.g. กู้ in both variants (vowel + mark and mark + vowel) look identical in about a dozen Thai fonts - the only exception being Apple's Thonburi font, which refuses to show the non-normalised form correctly. If a font can not correctly combine non-spacing marks, the font manufacturer should be notified. Kind regards, Gerriet.
