\pagedir TRT with pgfpages cause an incorrect result (shift out of page)

Question

Using \pagedir TRT with \pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm,landscape] from pgfpages package produce logical pages to be shifted out of page.

Same issue with layouts 4 on 1, 8 on 1, 16 on 1.

% lualatex 
\documentclass{article}
\usepackage[showframe]{geometry}
\usepackage{pgfpages}

\pgfpagesuselayout{2 on 1}[a4paper,border shrink=5mm,landscape]

\begin{document}

\pagedir TRT \bodydir TRT \pardir TRT

\Huge 

Page 1
 
\newpage

Page 2

\end{document}

Update 22/08/2020

I find a method to shift logical pages using \pagerightoffset, the problem is for every layout I need to add manually the amount of shift.

Example with 2 on 1 layout landscape page

% lualatex 
\documentclass{article}
\usepackage[showframe]{geometry}
\usepackage{pgfpages}


\pgfpagesuselayout{2 on 1}[a4paper,landscape]

\begin{document}

\pagerightoffset = .55\pgfphysicalwidth % <--
\pagedir TRT \bodydir TRT \pardir TRT 

\Huge 

Page 1
 
\newpage

Page 2

\end{document}

Answer 1

I think you'd have to make a new layout that lays out the pages RTL.

I change one line in the 2 on 1 layout from:

center=\pgfpoint{.75\pgfphysicalwidth}{.5\pgfphysicalheight}%

to:

center=\pgfpoint{-.25\pgfphysicalwidth}{.5\pgfphysicalheight}%

I'ts possible to do this with xpatch:

\usepackage{xpatch}
\expandafter\xpatchcmd\csname pgfpages@layout@2 on 1\endcsname
  {center=\pgfpoint{.75\pgfphysicalwidth}{.5\pgfphysicalheight}}
  {center=\pgfpoint{-.25\pgfphysicalwidth}{.5\pgfphysicalheight}}
  {}
  {}

For the layouts with more pages per page, you'd need multiple calls to xpatchcmd.

Full example:

\documentclass{article}
\usepackage[showframe]{geometry}
\usepackage{pgfpages}

\pgfpagesdeclarelayout{rtl 2 on 1}
{
  \edef\pgfpageoptionheight{\the\paperwidth} % landscaped by default
  \edef\pgfpageoptionwidth{\the\paperheight}
  \def\pgfpageoptionborder{0pt}
  \def\pgfpageoptionfirstshipout{1}
}
{
  \pgfpagesphysicalpageoptions
  {%
    logical pages=2,%
    physical height=\pgfpageoptionheight,%
    physical width=\pgfpageoptionwidth,%
    current logical shipout=\pgfpageoptionfirstshipout%
  }
  \ifdim\paperheight>\paperwidth\relax
    % put side-by-side
    \pgfpageslogicalpageoptions{1}
    {%
      border shrink=\pgfpageoptionborder,%
      resized width=.5\pgfphysicalwidth,%
      resized height=\pgfphysicalheight,%
      center=\pgfpoint{.25\pgfphysicalwidth}{.5\pgfphysicalheight}%
    }%
    \pgfpageslogicalpageoptions{2}
    {%
      border shrink=\pgfpageoptionborder,%
      resized width=.5\pgfphysicalwidth,%
      resized height=\pgfphysicalheight,%
      center=\pgfpoint{-.25\pgfphysicalwidth}{.5\pgfphysicalheight}% <- Shift second page to left hand side
    }%
  \else
    % stack on top of one another
    \pgfpageslogicalpageoptions{1}
    {%
      border shrink=\pgfpageoptionborder,%
      resized width=\pgfphysicalwidth,%
      resized height=.5\pgfphysicalheight,%
      center=\pgfpoint{.5\pgfphysicalwidth}{.75\pgfphysicalheight}%
    }%
    \pgfpageslogicalpageoptions{2}
    {%
      border shrink=\pgfpageoptionborder,%
      resized width=\pgfphysicalwidth,%
      resized height=.5\pgfphysicalheight,%
      center=\pgfpoint{.5\pgfphysicalwidth}{.25\pgfphysicalheight}%
    }%
  \fi    
}

\pgfpagesuselayout{rtl 2 on 1}[a4paper,border shrink=5mm,landscape]

\usepackage[bidi=basic-r,nil]{babel}
\babelprovide[import,main]{arabic}
\babelfont{rm}{Amiri}
      
\begin{document}

\Huge 
نص من اليمين الى اليسار

 الصفحة الأولى 1

\newpage

\Huge 
نص من اليمين الى اليسار

الصفحة الثانية 2

\end{document}

Answer 2

I find a solution which is inverting x coordinate inside every \pgfpoint command like this

\let\Pgfpoint\pgfpoint
\def\pgfpoint#1#2{\Pgfpoint{-1*#1}{#2}}

This patch needs to be added to commands in pgfpages containing the command \pgfpoint to limit the action of patch inside other commands from other packages

% lualatex 
\documentclass{article}
\usepackage[showframe]{geometry}
\usepackage{pgfpages}


\let\Pgfpoint\pgfpoint
\def\pgfpoint#1#2{\Pgfpoint{-1*#1}{#2}}
\pgfpagesuselayout{4 on 1}[a4paper,landscape]

\begin{document}

\pagedir TRT \bodydir TRT \pardir TRT 

\Huge 

Page 1
 
\newpage

Page 2

\newpage

Page 3

\newpage

Page 4

\end{document}