[HarfBuzz] Overlap of vocal with thai text

[Vignesh Raman]

Hi Konstantin,

Sorry to open this topic again.

On Mon, Mar 2, 2015 at 7:19 PM, Konstantin Ritt <ritt.ks at gmail.com> wrote:
> 2015-03-02 21:52 GMT+04:00 Vignesh Raman <rvignesh.raman at gmail.com>:
>>
>> I checked this thai font issue on a board with Qt 4.7.4 libs and this
>> happens with one particular font DejaVuSans.ttf.
>> When I tried DejaVuSansCondensed.ttf font the issue is not seen. I
>> wonder any of the harfbuzz-thai calls are not invoked for DejaVuSans
>> font?
>
>
> Might be a font issue. I already seen bugs related to an incorrect metrics
> in DejaVu fonts.

How to check if the font has incorrect metrics?


>
>>
>> Does font make a difference in harfbuzz bundled code
>> (src/3rdpart/hafbuzz) in Qt.
>
>
> Sure it does. Try inspecting the font's tables and metrics.

Is there a way to tell that the font ascent, descent values are incorrect?
Is there a ratio between ascent and descent that Qt expects to render
font correctly?

Thanks!

-- 
Regards,
Vignesh.