Re: [ft-devel] Haarmony LCD rendering

[Alexei Podtelezhnikov]

On Wed, Aug 9, 2017 at 6:15 AM, Markus Trippelsdorf
<address@hidden> wrote:
> On 2017.08.09 at 12:10 +0200, Werner LEMBERG wrote:
>>
>> > Unfortunately, it seems Firefox now cuts off many glyphs on the
>> > right side. A lowercase i or l can become almost invisible.
>>
>> IIRC, this is a bug in Firefox; it relies on a certain glyph buffer
>> layout that is not covered by the API but (incorrectly) derived from
>> FreeType's internal representation.
>
> Yes, the fix is already in Chromium, but Firefox needs it, too:
> https://skia.googlesource.com/skia/+/d1f2d15b36f6a6a9d199581b998a7ca924a1f1a8%5E%21/

I strongly suspect that this fix is inadequate. Skia continues to
pre-allocate the buffer too early. The fix just fits the FreeType
buffer in the pre-allocated space. It happens to work for ClearType
because we shrunk our buffer in this case. The default LCD image, on
the other hand, is now a bit larger, so it won't fit in the
pre-allocated space. I do not understand why Skia pre-allocates the
buffer instead of just taking what FreeType returns. That would be a
better fix.