Re: [css-text] Shaping Isolation and Layout Separation of Inlines

On 08/18/2014 06:45 PM, John Daggett wrote:
> fantasai wrote:
>
>> I think there are three classes of guidelines here, actually:
>>
>>     1. Must not break shaping. (No style change case. You have no excuse.)
>>     2. Should not break shaping, if possible. YMMV depending on
>>        implementation/font technology. Less breakage = better.
>>     3. Must break shaping.
>>
>> And I think we should be able to give interoperable results
>> on 1 and 3.
>
> Yeah, I think this makes sense.

Cool. So, just to go back to the original proposal:
   http://lists.w3.org/Archives/Public/www-style/2014Aug/0217.html

Cases proposed to fall under #3 are those listed:
   A. one of margin/border/padding are non-zero
   B. vertical-align is not 'baseline'
   C. it is a bidi isolation boundary

Everything else is #1 or #2 (which needs some further wordsmithing).

Thoughts/considerations?

> There may cases here where shaping shouldn't break but the final
> presentation may be tricky. For example, color changes within a
> pair of characters that form a ligature. For this situation I
> don't think you can say anything other than implementations make
> a "best effort" to display something sensible. Gecko solves the
> color change by coloring 1/nth of the resulting ligature formed
> from n characters. Sorta works sometimes but calling this a hack
> is certainly fair. :)

Agreed. :)

~fantasai

Received on Tuesday, 19 August 2014 03:17:30 UTC