[latex3-commits] [git/LaTeX3-latex3-latex3] master: A few notes on XeTeX backend code (8ff80cea1)

[Joseph Wright]

Repository : https://github.com/latex3/latex3
On branch  : master
Link       : https://github.com/latex3/latex3/commit/8ff80cea100e663003b0323f1e40f23d7152bcda

>---------------------------------------------------------------

commit 8ff80cea100e663003b0323f1e40f23d7152bcda
Author: Joseph Wright <joseph.wright at morningstar2.co.uk>
Date:   Tue Sep 1 16:34:12 2020 +0100

    A few notes on XeTeX backend code


>---------------------------------------------------------------

8ff80cea100e663003b0323f1e40f23d7152bcda
 l3backend/l3backend-basics.dtx | 4 +++-
 l3backend/l3backend-box.dtx    | 4 ++--
 l3backend/l3backend-draw.dtx   | 4 +++-
 3 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/l3backend/l3backend-basics.dtx b/l3backend/l3backend-basics.dtx
index a90cd6bb0..78508f85e 100644
--- a/l3backend/l3backend-basics.dtx
+++ b/l3backend/l3backend-basics.dtx
@@ -367,7 +367,9 @@
 % \end{macro}
 %
 % \begin{macro}{\__kernel_backend_scope_begin:, \__kernel_backend_scope_end:}
-%   Scoping is done using the backend-specific specials.
+%   Scoping is done using the backend-specific specials. We use the versions
+%   originally from \texttt{xdvidfpmx} (\texttt{x:}) as these are well-tested
+%   \enquote{in the wild}.
 %    \begin{macrocode}
 \cs_new_protected:Npn \__kernel_backend_scope_begin:
   { \__kernel_backend_literal:n { x:gsave } }
diff --git a/l3backend/l3backend-box.dtx b/l3backend/l3backend-box.dtx
index 78cf2d9eb..42ffec7e9 100644
--- a/l3backend/l3backend-box.dtx
+++ b/l3backend/l3backend-box.dtx
@@ -250,7 +250,7 @@
 %</luatex|pdftex>
 %    \end{macrocode}
 %
-% \subsection{\texttt{dvipdfmx} backend}
+% \subsection{\texttt{dvipdfmx}/\XeTeX{} backend}
 %
 %    \begin{macrocode}
 %<*dvipdfmx|xetex>
@@ -280,7 +280,7 @@
 %
 % \begin{macro}{\@@_backend_rotate:Nn}
 % \begin{macro}{\@@_backend_rotate_aux:Nn}
-%   Rotating in \texttt{(x)}dvipdmfx can be implemented using either PDF or
+%   Rotating in \texttt{dvipdmfx}/\XeTeX{} can be implemented using either PDF or
 %   backend-specific code. The former approach however is not \enquote{aware}
 %   of the content of boxes: this means that any embedded links would not be
 %   adjusted by the rotation. As such, the backend-native approach is preferred:
diff --git a/l3backend/l3backend-draw.dtx b/l3backend/l3backend-draw.dtx
index 00e9144e4..22248917f 100644
--- a/l3backend/l3backend-draw.dtx
+++ b/l3backend/l3backend-draw.dtx
@@ -581,7 +581,9 @@
 %   matrix into rotations and a scaling, then use those operations as they
 %   are handled by the backend. (There is backend support for matrix operations in
 %   \texttt{dvipdfmx}/\XeTeX{}, but as a matched pair so not suitable for the
-%   \enquote{stand alone} transformation set up here.)
+%   \enquote{stand alone} transformation set up here.) The specials used here
+%   are from \texttt{xdvipdfmx} originally: they are well-tested, but probably
+%   equivalent to the \texttt{pdf:} versions!
 %    \begin{macrocode}
 \cs_new_protected:Npn \@@_backend_cm:nnnn #1#2#3#4
   {