[HarfBuzz] HB-NG and Qt

[Jonathan Kew]

On 6/11/14 20:10, Khaled Hosny wrote:
> On Thu, Nov 06, 2014 at 09:32:26AM -0800, Behdad Esfahbod wrote:
>> On 14-11-05 11:50 PM, Khaled Hosny wrote:
>>> Tahoma (at least the version shipped in Windows 7) has a kern table,
>>> but no kern feature in its GPOS table, so HarfBuzz will not apply the
>>> kern table as Behdad described. Uniscribe does not apply the kern
>>> table here either AFAICT, so I think the font is working as intended.
>>
>> That was indeed my thinking before.  From what I remember, Uniscribe *never*
>> applied the TrueType 'kern' table; it was left to applications to do that.
>>
>> So I think what I like to see is: on versions of Windows that ship with such
>> fonts, does notepad apply kerning?  If it does, we should do in HarfBuzz.
>> Otherwise I'm leaning towards keeping HarfBuzz as is.
>
> I tried notepad while testing this and it did not apply kerning for that
> font (I got kerning in few other random fonts I tried, just in case).

In the fonts where you did get kerning, is there a GPOS 'kern' feature 
present?

>
>> That said, "fixing" this is about three lines of code.  If Konstantin wants it
>> badly, I don't mind doing it.
>>
>> Jonathan, what do you think?
>
> I recall people complaining loudly when Firefox started using HarfBuzz
> for Latin in Windows because it applied kerning to some fonts that other
> Windows applications did not kern (not sure what fonts/Windows versions
> were involved, though).

Right. There appear to be some fonts out there that have overly 
"aggressive" kern tables, but as Windows apps in general don't apply the 
kerning, nobody notices. Then when someone does start applying the 
kerning, people don't like the result.

JK