Re: Tibetan fonts

[Tom]

Hi Oliver

བཀྲ་ཤིས་བདེ་ལེགས། to you as well.
Thank you for such a long detailed response.
As you can see yourself, all compositions are missing, yata and rata are 
placed but not supescripted or subscripted. Vowels are present but
placed not properly.

I have tried as well TibMachUni but from Arch distro. More fonts I've 
tried are:
YagpoTibetanSambhotaUni, NotoSerifTibetan, Jomolhari, MonlamUniChouk,
and great Qomolangma-* which I prefer.

With your experience about ISO/Unicode would you mind
to help and bring tibetan fonts to groff and troff?

You asked for source code, it is just basic test.
Thirstily I have just added/installed fonts to 
/../groff/site-font/devpdf and /../devps with install-font.sh script. 
Next, mounted
and used sample of tibetan text.

If I can suggest you to use YagpoTibetanUni font for test, 
https://www.fontspace.com/yagpo-tibetan-sambhota-uni-font-f44981

I used text:
༄༅། །དབུ་མ་རྩ་བའི་ཚིག་ལེའུར་བྱས་པ་ཤེས་རབ་ཅེས་བྱ་བ་བཞུགས་སོ།
ཧཱུྃ༔ ཨོ་རྒྱན་ཡུལ་གྱི་ནུབ་བྱང་མཚམས༔
Warning output from groff was:
troff:<standard input>:16: warning: special character 'u0F04' not 
defined ...

For test you can use directly:

\[u0F04]\[u0F05]\[u0F0D] 
\[u0F0D]\[u0F51]\[u0F56]\[u0F74]\[u0F0B]\[u0F58]\[u0F0B]\[u0F62]\[u0FA9]\[u0F0B]\[u0F56]\[u0F60]\[u0F72]\[u0F0B]\[u0F5A]\[u0F72]\[u0F42]\[u0F0B]\[u0F63]\[u0F7A]\[u0F60]\[u0F74]\[u0F62]\[u0F0B]\[u0F56]\[u0FB1]\[u0F66]\[u0F0B]\[u0F54]\[u0F0B]\[u0F64]\[u0F7A]\[u0F66]\[u0F0B]\[u0F62]\[u0F56]\[u0F0B]\[u0F45]\[u0F7A]\[u0F66]\[u0F0B]\[u0F56]\[u0FB1]\[u0F0B]\[u0F56]\[u0F0B]\[u0F56]\[u0F5E]\[u0F74]\[u0F42]\[u0F66]\[u0F0B]\[u0F66]\[u0F7C]\[u0F0D]

Those are outputted in warning by groff as not defined.
Most of fonts I've tried, outputs same warnings.
And Mounted BabelStoneTibetan, TibMachUni and Jomolhari fonts renders 
pdf but with failed compositions.


Regards,
Tom







> Tibetan script vertical stacks are built in a quite regular fashion. It 
> is possible to completely rely on Latin (ASCII) input and have the 
> ligature mechanism of the font perform the necessary acrobatics.
>
> Long before Unicode was widely accepted and in use, I had written such a 
> system for TeX/LaTeX: https://ctan.org/pkg/ctib4tex
>
> The ligature in question appears on line no. 2 of page 8 of the pdf 
> documentation. §3. 2 Known transliteration problems" on p. 5 of said 
> document demonstrates the problem of consonant clusters which may lead 
> to incorrect ligatures.
>
> At that time, I still relied on Metafont sources. I never reworked the 
> package for Unicode fonts, but on the other hand this is an incentive to 
> create a Latin-input driven Tibetan macro package for groff which also 
> accepts native Tibetan as input.
>
> May I kindly ask you to post the source code of your trial file? Then I 
> can dig deeper into the ligature problem.
>
> Best regards,
>
> Oliver.
>
>
>
> On 21/01/2024 18:48, Deri wrote:
> > On Sunday, 21 January 2024 00:28:42 GMT Oliver Corff via wrote:
> > > Hi Tom,
> > >
> > > བཀྲ་ཤིས་བདེ་ལེགས།
> > >
> > > (sorry, I forgot the shad)
> > >
> > > have you tried the font TibMachUni-1.901b.ttf? It is available via
> > >
> > > package manager e.g. in Fedora 39.
> > >
> > > Can post a source file for your examples, please? I may try in tomorrow.
> > >
> > > Best regards,
> > >
> > > Oliver.
> > >
> > > On 21/01/2024 00:09, Tom wrote:
> > > > Hi,
> > > >
> > > > I did typeset few books in Heirloom Troff with quite good outcome.
> > > > For next book I need to use Tibetan font and unfortunately I can't
> > > > make work in Heirloom Troff and Groff, only Neatroff does work.
> > > >
> > > > Right now I'm eager to completely switch to Groff. I can make any font
> > > > work in Groff but not Tibetan. To my basic knowledge, I guess it is
> > > > all about blwm and blws not accessible. There are only few Tibetan
> > > > fonts with complex glyph composition which works in Neatroff. In groff
> > > > I have managed only BabelStoneTibetan to display but several glyphs
> > > > doesn't compose.
> > > >
> > > > For viewing I have attached Groff and Neatroff pdfs.
> > > >
> > > > YagpoTibetanUni: 100% composing in Neatroff but 100% failed in Groff
> > > > and Heirloom troff.
> > > > BabelStoneTibetan: 100% failed in Groff and Neatroff.
> > > >
> > > > I have tried various tibetan fonts, as well NotoSerifTibetan present
> > > > in linux repositories. All those fonts don't work and groff yields:
> > > > troff:<standard input>:20: warning: special character 'u0F04' not defined
> > > > troff:<standard input>:20: warning: special character 'u0F05' not defined
> > > > troff:<standard input>:20: warning: special character 'u0F0D' not defined
> > > > ...
> > > >
> > > > If I understand enough, the warnings are about missing glyph mappings.
> > > >
> > > > Would you mind to have a look and check if Tibetan fonts are possible
> > > > to make work in Groff ? I appreciate for any hints, and direction I
> > > > can follow to make it happen.
> > > >
> > > >
> > > > Regards,
> > > > Tom
> > Hi Tom,
> >
> > Using the font suggested by Oliver (after installing it with Peter Schafter's
> > install-font.sh script) and using the latest unicode aware pdf generation
> > version of groff (awaiting release by Branden), with this script:-
> >
> > .ft TibetanR \" What I called Oliver's suggested font
> > .ps 24
> > .vs 28
> > .pdfbookmark 1 བཀྲ་ཤིས་བདེ་ལེགས།
> > བཀྲ་ཤིས་བདེ་ལེགས།
> > .br
> > .ad l
> > ༄༅། །དབུ་མ་རྩ་བའི་ཚིག་ལེའུར་བྱས་པ་ཤེས་རབ་ཅེས་བྱ་བ་བཞུགས་སོ།
> > ཧཱུ༔ ཨོ་རྒྱན་ཡུལ་གྱི་ནུབ་བྱང་མཚམས༔
> >
> > It produced the attached.
> >
> > Cheers
> >
> > Deri
>
> --
> Dr. Oliver Corff
> Wittelsbacherstr. 5A
> 10707 Berlin
> GERMANY
> Tel.: +49-30-85727260
> mailto:oliver.corff@email.de