Re: [css3-writing-modes] The original issues of font-dependent glyph orientation

On 10/3/2011 5:31 PM, fantasai wrote:
> If I understand correctly, this means legacy fonts (which would be, 
> all the fonts in existence today) would not be using most of their 
> 'vert' glyphs, 

I'd say that most of the 'vert' transformations would be used, both 
counting the numbers of entries in a typical 'vert' feature, and 
counting the number of times they are applied in a document: small 
katakana, square katakana symbols, a few punctutations, and the brackets 
if we let SB go through 'vert', dominate that number.

> but that going forward we will have a reliable, understandable system 
> for vertical typesetting. If so, I believe this is the right approach 
> for Unicode

Good.

> . It does leave open the question of how typesetting systems are to 
> deal with legacy fonts, which do not support the new feature

Looking at the current 'vert' lookups, the entries that are not for T 
characters are not doing more than rotating the glyphs; in other word, 
even if that feature existed today, it seems that the existing fonts 
would not use it.

Eric.