Re: [ft-devel] [GSoC] CID font support, and others

[Alexei Podtelezhnikov]

Ewald,

Here
http://git.savannah.gnu.org/cgit/freetype/freetype2.git/tree/src/psaux/pshints.c?h=ewaldhew-wip#n1251
FT_DivFix is followed by 2 FT_MulFix's. It could be faster to do
combine them into two FT_MulDiv's.

Here
http://git.savannah.gnu.org/cgit/freetype/freetype2.git/tree/src/psaux/pshints.c?h=ewaldhew-wip#n1583
The fixed number is the first argument. This is contrary to FT_MulFix
recommendation to place larger bit-value second.

This is just two things I noticed quickly. If you have time, you might
find some speed gains this way. I did this a while back for the rest
of FreeType when the Adobe engine was just donated. I did not want to
mess with it then.

Alexei


On Thu, Aug 17, 2017 at 10:34 PM, Ewald Hew <address@hidden> wrote:
>> Are you benchmarking a 32-bit build? How unfashionable of you :)
>
> The system-provided version is 32-bit (not sure why??). After properly
> linking I have a 64-bit build, and FT_DivFix does not seem to be a
> problem any more :-)
>
>> https://savannah.nongnu.org/bugs/?43248
>
>> Now I have that the glyphpath procedures take a bulk of the time.
>> What's interesting is the hinting functions get called from these,
>> regardless of the load flags, and probably explains why it's roughly
>> the same hinted or not. This seems wrong IMO, as we should be ignoring
>> hints accordingly, but the call graph shows `cf2_hintmap_build',
>> `cf2_hintmap_insertHint', and the like being used, which account for a
>> sizeable chunk of time.
>>
>> I will investigate this further. Probably the `hinted' flag is being
>> ignored somehow.
>
> Some success here.
>
> Disabling hinting stuff properly when hinting is off gave a speed
> boost of about a third. Still not as much an improvement as turning
> off hinting in the old engine.
>
> Here is my data from testing:
> FT_Load_Glyph:`adobe' (units: us/op)
> flags  time
> 0x0    7.844
> 0x1    5.212
> 0x2    5.079
>
> I've pushed the code changes to `ewaldhew-wip'. Please check.
>
> Ewald



-- 
Alexei A. Podtelezhnikov, PhD