Re: Role of the font in deciding the cluster boundaries

On 13/03/14 2:35 PM, Cibu Johny (സിബു) wrote:

> It's boundary inside a grapheme cluster is decided by an explicit virama
> in its shaping.

This is where the character-based determination of a graphemic entity 
ceases to be sufficient, though, because different fonts may display the 
same conjunct with or without explicit (visible) virama; indeed, the 
same font may display the same conjunct in different ways depending on 
language system tagging (e.g. a conjunct may shape as a stacked ligature 
for Sanskrit, but with an explicit virama for Hindi).

Because of modern rules for ordering ikar and reph relative to explicit 
virama, the OpenType Indic specs include different conjunct ligature 
shaping features for those involving true half forms and those involving 
explicit virama, and reordering takes place between application of the 
two features. Something similar could be done in terms of isolating 
Cibu's 'explicit graphemes', but it means interacting with the layout 
engines and fonts, which strikes me as an incredibly complicated way of 
handling CSS first-letter styling.

JH

Received on Thursday, 13 March 2014 23:23:33 UTC