[HarfBuzz] Sinhala split matra

[Behdad Esfahbod]

I reiterate what I've said many many times on this list already.  Hopefully
this puts an end to this particular topic.  More below.


On 12-11-13 06:15 PM, Harshula wrote:
> Hi Behdad & Jonathan,
> 
> On Tue, 2012-11-13 at 12:40 -0800, Behdad Esfahbod wrote:
>> Jonathan and I decided to workaround the Sinhala issue with split matras and
>> free fonts, such that they continue working with new HarfBuzz.  That's in
>> master now.
> 
> 1) GNU Free Font maintainer, Steve, went to a lot of effort to make
> FreeSerif work with Uniscribe and the Harfbuzz behaviour we agreed to in
> September.
> (http://lists.freedesktop.org/archives/harfbuzz/2012-September/002458.html). See SVN version of FreeSerif. He is also working hard to do a release soon.

Good that he did.  Because in general we don't care about supporting fonts
that are broken with Uniscribe.


> 2) You refer to "free fonts". Are you referring to GNU Free Font or to
> the two GPL'd fonts that support Sinhala? One of them is deprecated,
> there are problems with glyphs etc, and the other, FreeSerif, that is
> meant to replace the former works well with Harfbuzz from a week ago.

I meant fonts that were designed to work with the Free Software shaping
engines (old HarfBuzz, Pango, ICU LayoutEngine).


> 3) The big win, from the behaviour agreed to in September, is that any
> Windows font will just work with Harfbuzz. With the FreeSerif changes,
> that meant that all maintained fonts just work. From the perspective of
> actual Linux Sinhala script users, that increases their font options
> significantly.

What we decided to do yesterday allows for both set of fonts to work with
harfbuzz-ng.  This is a superset of the fonts that HarfBuzz before yesterday
could render correctly, and a superset of fonts that worked with old HarfBuzz
/ Pango, and a superset of fonts that work with Uniscribe.  So it can't be worse.


> 4) Commit 0736915b8ed789a209205fec762997af3a8af89c ([Indic] Decompose
> Sinhala split matras the way old HarfBuzz / Pango did) has a bug. The
> five fonts I test with do not render correctly now. I suspect no fonts
> render correctly with current TOT Harfbuzz. i.e. A regression. Try කේ
> (<U+0d9a><U+0dda>).

Ouch.  Fix pushed out.  We will make another release at the end of the week.


> 5) Since this is a FOSS project, any chance you and Jonathon could
> elaborate a bit on the problem you guys are trying to fix and the
> reasoning behind the decision to overturn what was agreed to in
> September?

I already explained the problem in response to your email back in July:

  http://lists.freedesktop.org/archives/harfbuzz/2012-July/002261.html


-- 
behdad
http://behdad.org/