Cfrgtkky

I am working with a project which requires LuaLaTeX (TeX Live 2018) and the Noto Serif Myanmar font. I need a few words of Burmese only. The MWE works well with XeLaTeX. But LuaLaTeX has a problem with the ligatures. Is there any way to get this to work with LuaLaTeX and the used Noto Serif Myanmar font (besides setting them with XeLaTeX and include them as graphics, e.g. with https://ctan.org/pkg/standalone)?

documentclass[landscape]{memoir}



usepackage{fontspec,polyglossia,url}



newfontfamily{burmeseFamily}{NotoSerifMyanmar-Regular.ttf}

newfontfamily{burmeseFamilyDecom}{MyanmarMN}

newcommand{burmeseTest}[1]{

{burmeseFamily{} #1}

hfill

{burmeseFamilyDecom{} #1}}



begin{document}



burmeseTest{င်းကွန်းင်းလောင်းတော်ကြီး}



bigskip

burmeseTest{မ္မတီခေါင်းလောင်းကြီး}





vfill

Might be usefull: url{https://r12a.github.io/pickers/burmese/}

end{document}

The RHS is just for comparison, the LHS is what I really need.

XeLaTeX (correct):

LuaLaTeX (wrong):

The website https://r12a.github.io/pickers/burmese/ might be useful for an analysis of the ligatures. Thanks to ShreevatsaR's comment below, the site https://en.wikipedia.org/wiki/Complex_text_layout might give some relevant information. If you are not familiar with the Noto fonts, you might want to read https://en.wikipedia.org/wiki/Noto_fonts.

Update. Version 2.7b (2019/02/12) of https://ctan.org/pkg/fontspec adds (experimental) support for additional rendering engines such as Harfbuzz or Graphite. I was not able to do a correct set up with those engines, yet, see also the comments on https://tex.stackexchange.com/a/441914/128553 below.

Here is a sample using my Luatex-harfbuzz-shaper:

documentclass[landscape]{memoir}



usepackage{harfbuzz}

% usepackage{fontspec,polyglossia,url}

usepackage{url}



fontburmeseFamily={Noto Sans Myanmar:+script=mymr;+language=mya} at 12pt

fontburmeseFamilyDecom={Noto Sans Myanmar:+script=dflt;+language=dflt} at 12pt

newcommand{burmeseTest}[1]{

{burmeseFamily{} #1}

hfill

{burmeseFamilyDecom{} #1}

}



begin{document}



burmeseTest{င်းကွန်းင်းလောင်းတော်ကြီး}



bigskip

burmeseTest{မ္မတီခေါင်းလောင်းကြီး}





bigskip

Might be usefull: url{https://r12a.github.io/pickers/burmese/}

end{document}

Note that it expects the Noto Sans Myanmar is installed on your system. You also need to install Luaharfbuzz on your system.

This is the result:

At the moment, LuaTeX does not support most of the world's scripts, including Burmese and other Brahmi-derived scripts. This is because it supports only simple scripts where characters are laid out one after the other; not scripts that require complex text layout.

There is some rudimentary support for Devanagari, and possibly for Malayalam, but not for Burmese as far as I know. Your options if you need to use such an “unsupported” script are:

• Just use XeTeX (or pdfTeX with a package for your script/language, if it exists), instead of LuaTeX (e.g. if you're using LaTeX, compile with xelatex instead of lualatex).




• Generate the text in another application (like XeTeX or whatever), and insert it as images into your LuaTeX document.




• Use one of the “experimental” ways of using a library (Harfbuzz) from LuaTeX, for text shaping. Some links (that you'll have to make sense of yourself): tatzetwerk/luatex-harfbuzz, deepakjois/luatex-harfbuzz, michal-h21/luatex-harfbuzz-shaper (associated mailing list post), recent article by two of the LuaTeX developers.




• Figure out how support is done in LuaTeX for Devanagari, and imitate it for Burmese (and other scripts). (I don't know how easy this is: on the one hand Harfbuzz is a long-running project with a lot of complexity; on the other hand on a cursory look the small amount of support code in LuaTeX for Devanagari seems to be adequate for some common purposes… though I haven't tested it in any detail.)

You should also ask on the LuaTeX mailing list: a couple of months ago there was a claim that no one had ever asked the LuaTeX developers for support for such scripts!

@ShreevatsaR has given some good thoughts. However, since I only needed two words, I included the words as PDF. This works reasonably and economically as I do not need to invest much time to try to make his suggestions work as I have never worked with the tools he suggested and my attempt with a correct harfbuzz setup ended in failure.
In case someone is interested in the details:

We compile the following file Burmese.tex with XeLaTeX:

documentclass[11pt,tikz,border=0ex]{standalone}



usepackage{fontspec,polyglossia,url}



%This is necessary to scale the Burmese font. 

setmainfont{texgyrepagella-regular.otf}



%You may want to choose NotoSerifMyanmar-Medium.ttf or a different font for a better optical match

newfontfamily{burmeseFamily}{NotoSerifMyanmar-Regular.ttf}[Scale=MatchLowercase]

%There might be simpler ways to get equivalent results. 

newcommand{burmeseFont}[1]{tikz node[inner sep=0pt] {burmeseFamily{}#1};}



begin{document}



burmeseFont{င်းကွန်းင်းလောင်းတော်ကြီး}



burmeseFont{မ္မတီခေါင်းလောင်းကြီး}



end{document}

This gives the file Burmese.pdf with the two following pages:

We can use this file as follows:

documentclass[11pt]{memoir}



usepackage{fontspec,polyglossia,url,pdfpages}



setmainfont{texgyrepagella-regular.otf}



%Lowering the PDF gives matching baselines 

newcommand{burmeseA}

{mbox{lower 1.00exhbox{includegraphics[page=1]{Burmese.pdf}}}}

newcommand{burmeseB}

{mbox{lower 1.00exhbox{includegraphics[page=2]{Burmese.pdf}}}}



begin{document}



Lorem ipsum burmeseA{} dolor sit manet. 



Et burmeseB{} nil nisi colloquor. 



end{document}

To get the following result.

Matching font size and mainfont in both files are important. One can vary the font size and styles in the file Burmese.tex in case different typefaces are needed.
One note: The Burmese letters in the second PDF are not copyable.