Re: [ft-devel] How to determine if horizontal hinting is happening?

[Adam Goode]

On Tue, Feb 20, 2018 at 5:10 PM, Behdad Esfahbod <address@hidden> wrote:
> On Tue, Feb 20, 2018 at 11:04 AM, Alexei Podtelezhnikov <address@hidden>
> wrote:
>>
>> >>
>> >> > I think Skia does, by default, a 4x1 subpixel grid.
>> >>
>> >> ... which is almost the same as 3x1, which you would get for free from
>> >> LCD rendering with 3 channels shifted by 1/3.. 4x1 is such a minor
>> >> gain for a huge cache waste. Just a suggestion.
>> >
>> > May I ruin your suggestion by suggesting that LCD images are stored four
>> > bytes a pixel? ;)
>>
>> Do you then average the middle bytes for the middle channel, or
>> interpolate?
>> That is weird, but alright.
>
>
> I have no idea what you're talking about.
>
> Ignore my 4x1 thing. I said I think that's what Skia does. And I had that in
> mind with grayscale, not with subpixel rendering.
>
> --
> behdad
> http://behdad.org/


To try to answer my question from before (please correct my errors!):


Any of these conditions result in no horizontal hinting:

- FT_LOAD_NO_HINTING is set.

- FT_LOAD_TARGET_LIGHT is set.

- FT_LOAD_TARGET_NORMAL is set, the autohinter is not used, and
interpreter-version == TT_INTERPRETER_VERSION_40, and hinting_engine =
FT_HINTING_ADOBE.


Otherwise, horizontal hinting may occur.


Specifically:

- FT_LOAD_TARGET_MONO will hint horizontally.

- FT_LOAD_TARGET_LCD will hint horizontally (?)

- FT_LOAD_TARGET_V will hint horizontally (?)


Does this seem right?



Thanks,

Adam