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

[Adam Goode]

On Mon, Feb 19, 2018 at 5:06 PM, Alexei Podtelezhnikov
<address@hidden> wrote:
>> Also, I don't think it's necessarily too late to get the information
>> after FT_Load_Glyph is called.
>
> Adam, Ben,
>
> To be honest, I do not quite follow how Chromium does text rendering.
> It was under impression that you guys do font atlasing (aka preloading
> of font texture). We just provided presetting of bitmap dimensions to
> facilitate that if you wish. This is a sort of GPU caching system. Now
> you are asking about subpixel positioning, which is basically
> uncacheable because you would have unique bitmap for each subpixel
> position. I am totally confused now. Well, you can use LCD rendered
> bitmaps as 3 individual bitmaps shifted by 1/3 pixel and have that
> granularity but not truly continuous. I just wish I could understand
> where Chromium is going in order to help more intelligently.
>
> Alexei


Hi Alexei,

Sorry for any confusion. Just to be clear, I'm not on the Chrome
graphics team, nor do I speak authoritatively for them. I'm just
trying to clean up some of this code in Chrome that I was seeing some
issues with.


My understanding of the situation is that the non-subpixel case is not
the common case, but still important (standard DPI with the horiztonal
hinting algorithms).
I'm not an expert on how the code works, but my understanding is that
subpixel positioning is the norm. I don't know what is cached where,
but it looks like it is all within Skia?


For reference, this is a pretty good document on some of the issues
(though it doesn't really cover caching):
https://docs.google.com/document/d/1wpzgGMqXgit6FBVaO76epnnFC_rQPdVKswrDQWyqO1M/edit


Thanks,

Adam