[luatex] possible engine bug: glyphs displaced

[Ulrike Fischer]

I'm forwarding a discussion from the luaotfload issue tracker as it
is possible that it indicates a bug introduced between version 1.0.0
and 1.0.4

In the following document the ^^^^0645 is displaced to the left.
With luatex 1.0.0. (miktex) only if it is used in a \hbox. 
With luatex 1.0.4. in all three cases. 

The luaotfload version was the same, as fontloader I used the newest
from the context minimals. 

So it looks as if some change in the engine was made -- perhaps to
correct the \hbox error -- which made the problem worse.


Some more details and some pictures can be found here:
https://github.com/lualatex/luaotfload/issues/410

Disclaimer: I can't read or write arabic or some other
right-to-left-script.  



\documentclass{article}

\begin{document}
\textdir TRT

\font\amiri={file:amiri-regular.ttf:script=arab} at 80pt
\amiri

^^^^0637 ^^^^0645^^^^062d^^^^064a^^^^0637\par

\leavevmode\hbox dir TRT {^^^^0637 ^^^^0645^^^^062d^^^^064a^^^^0637}

\vbox dir TRT {^^^^0637 ^^^^0645^^^^062d^^^^064a^^^^0637}

\end{document}


-- 
Ulrike Fischer 
http://www.troubleshooting-tex.de/