[HarfBuzz] Retrieving optical size info?

[Behdad Esfahbod]

On 12-11-27 05:37 PM, Khaled Hosny wrote:
> On Mon, Nov 26, 2012 at 02:03:15PM +0200, Behdad Esfahbod wrote:
>> On 12-11-24 10:58 PM, Khaled Hosny wrote:
>>> On Sat, Nov 24, 2012 at 01:05:26AM -0500, Behdad Esfahbod wrote:
>>>> On 12-11-23 07:42 PM, Khaled Hosny wrote:
>>>>
>>>>> (Background: I’m almost done with porting XeTeX from ICU LayoutEngine to
>>>>> HarfBuzz, one of the few things remaining is getting optical size. The
>>>>> current code uses some internal LE API and I want to move away from this
>>>>> as possible).
>>>>
>>>> Sure, I'll implement it in HarfBuzz for you!
>>>
>>> Great!
>>
>> Done.  Untested though.  Let me know if it works!
> 
> Thanks Behdad. It seems that looking for ‘size’ feature under default
> script does not work, with the attached patch which makes it check all
> GPOS features, things work fine.

Technically speaking those are font bugs.  But I'll fix.


> Now what remains is handling fonts with broken ‘size’ feature that AFDKO
> used to make prior 2006, but I’m yet to find documentation for it (Adobe
> is said to have sent some explanation for a heuristic to handle broken
> ‘size’ features to OpenType mailing list somewhere in 2006, but I don’t
> have access to list archives).

Right...  It's a bad hack.  I have the Adobe OpenType code, I can check, but
IIRC the offset was computed from the beginning of the table, or something
like that, and the hack simply looks in both places...  I'll take a look,
though I'm spending time with family this week in Istanbul, so may be slow to
do this.

behdad



> Regards,
>  Khaled
> 

-- 
behdad
http://behdad.org/