Re: [ft-devel] Regarding head-table Bit 3: Force ppem to integer values for all internal scaler math

[Behdad Esfahbod]

On 14-11-26 08:58 PM, Werner LEMBERG wrote:
> 
>> Essentially it's about whether FreeType should respect bit 3 of
>> head-table flags:
>>
>>   http://www.microsoft.com/typography/otspec/head.htm
>>
>> and implemented here:
>>
>>   https://github.com/behdad/freetype/blob/master/src/truetype/ttobjs.c#L1189
>>
>> I don't think applying this rounding makes sense when not doing
>> bytecode hinting.  Indeed, it breaks linear scaling, etc.
> 
> Sounds sensible to disable it for the non-hinting case.  Can you
> prepare a patch?

Ouch, wouldn't work, as the face metrics are independent of load flags :(.

Not sure how to proceed, short of reverting the commit from 2011.  Or perhaps
disable the current behavior if TT_USE_BYTECODE_INTERPRETER is not set.  But
that would result in even harder-to-debug situations...


> And do you have data on Windows behaviour for TrueType fonts with and
> without hints?  Or Apple data, which might be relevant also since they
> don't use hints...

I don't.

-- 
behdad
http://behdad.org/