Re: Unicode rendering problems

[Patrick McCarty]

[resend to bug-lilypond without attachments]

Hi Didi,

On 2010-05-05, Patrick McCarty wrote:
> On 2010-05-05, Didi Kanjahn wrote:
> > 
> > Khmer Unicode does not get rendered correctly #1.
> > 
> > A major bug in the rendering of Khmer Unicode was fixed in
> > version 2.13.3.  With 2.13.3 the first glyph-sequence of each
> > line (also line 6) was now rendered as can be seen in line 1,
> > 3 and 4 of 'test Khmer Unicode 2-13-3.pdf'. Before version
> > 2.13.3 all Khmer fonts rendered those lines as in line 2 and
> > 6.
> > 
> > However, in version 2.13.19 there is a new problem with
> > rendering Khmer Unicode (it started at an earlier version, but
> > I don't know when exactly), leading to many dotted circles.
> > From that ensuing result, it can be assumed that the
> > instructions of the Unicode rendering engine (not part of the
> > font) are being carried out (in particular the shifting of
> > certain glyphs/symbols within a cluster), but the instructions
> > of the OpenType tables that are part of the font are not being
> > carried out. Please see 'test Khmer Unicode 2-13-19.pdf'.
> > 
> > Please disregard the last dotted circle in each line for this
> > particular bug report. See below under 'Khmer Unicode does not
> > get rendered correctly #4' for details.
> 
> I suspect that the bug was introduced after we upgraded Pango to
> version 1.26.0.  There are some major problems rendering Syriac
> glyphs as well, as compared to 1.24.* versions.

I have done some more tests, and I can confirm that the new
problems you are seeing are due to LilyPond upgrading from Pango
1.24.4 to Pango 1.26.0.

This happened in LilyPond 2.13.7.

I'm pretty sure Pango 1.28 has the same problem, too.

Do you want to file a bug report on the Pango tracker
(https://bugzilla.gnome.org/), or would you like me to look into
it?

Thanks,
Patrick