% \iffalse meta-comment
%
%% File: l3backend-pdf.dtx
%
% Copyright (C) 2019-2025 The LaTeX Project
%
% It may be distributed and/or modified under the conditions of the
% LaTeX Project Public License (LPPL), either version 1.3c of this
% license or (at your option) any later version. The latest version
% of this license is in the file
%
% https://www.latex-project.org/lppl.txt
%
% This file is part of the "l3backend bundle" (The Work in LPPL)
% and all files in that bundle must be distributed together.
%
% -----------------------------------------------------------------------
%
% The development version of the bundle can be found at
%
% https://github.com/latex3/latex3
%
% for those people who are interested.
%
%<*driver>
\documentclass[full,kernel]{l3doc}
\begin{document}
\DocInput{\jobname.dtx}
\end{document}
%</driver>
% \fi
%
% \title{^^A
% The \pkg{l3backend-pdf} module\\ Backend PDF features^^A
% }
%
% \author{^^A
% The \LaTeX{} Project\thanks
% {^^A
% E-mail:
% \href{mailto:latex-team@latex-project.org}
% {latex-team@latex-project.org}^^A
% }^^A
% }
%
% \date{Released 2025-04-14}
%
% \maketitle
%
% \begin{documentation}
%
% \end{documentation}
%
% \begin{implementation}
%
% \section{\pkg{l3backend-pdf} implementation}
%
% \begin{macrocode}
%<*package>
%<@@=pdf>
% \end{macrocode}
%
% Setting up PDF resources is a complex area with only limited documentation
% in the engine manuals. The following code builds heavily on existing ideas
% from \pkg{hyperref} work by Sebastian Rahtz and Heiko Oberdiek, and
% significant contributions by Alexander Grahn, in addition to the specific
% code referenced a various points.
%
% \subsection{\texttt{dvips} backend}
%
% \begin{macrocode}
%<*dvips>
% \end{macrocode}
%
% \begin{macro}{\@@_backend_pdfmark:n, \@@_backend_pdfmark:e}
% Used often enough it should be a separate function.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_pdfmark:n #1
{ \__kernel_backend_postscript:n { mark #1 ~ pdfmark } }
\cs_generate_variant:Nn \@@_backend_pdfmark:n { e }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Catalogue entries}
%
% \begin{macro}{\@@_backend_catalog_gput:nn, \@@_backend_info_gput:nn}
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_catalog_gput:nn #1#2
{ \@@_backend_pdfmark:n { { Catalog } << /#1 ~ #2 >> /PUT } }
\cs_new_protected:Npn \@@_backend_info_gput:nn #1#2
{ \@@_backend_pdfmark:n { /#1 ~ #2 /DOCINFO } }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Objects}
%
% \begin{macro}{\@@_backend_object_new:}
% \begin{macro}[EXP]{\@@_backend_object_ref:n, \@@_backend_object_id:n}
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_new:
{ \int_gincr:N \g_@@_backend_object_int }
\cs_new:Npn \@@_backend_object_ref:n #1 { { pdf.obj #1 } }
\cs_new_eq:NN \@@_backend_object_id:n \@@_backend_object_ref:n
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}
% {
% \@@_backend_object_write:nnn, \@@_backend_object_write:nne,
% \@@_backend_object_write_aux:nnn
% }
% \begin{macro}
% {
% \@@_backend_object_write_array:nn ,
% \@@_backend_object_write_dict:nn ,
% \@@_backend_object_write_fstream:nn ,
% \@@_backend_object_write_stream:nn
% }
% \begin{macro}{\@@_backend_object_write_stream:nnn}
% This is where we choose the actual type: some work to get things
% right. To allow code sharing with the anonymous version, we use an
% auxiliary.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_write:nnn #1#2#3
{
\@@_backend_object_write_aux:nnn
{ \@@_backend_object_ref:n {#1} }
{#2} {#3}
}
\cs_generate_variant:Nn \@@_backend_object_write:nnn { nne }
\cs_new_protected:Npn \@@_backend_object_write_aux:nnn #1#2#3
{
\@@_backend_pdfmark:e
{
/_objdef ~ #1
/type
\str_case:nn {#2}
{
{ array } { /array }
{ dict } { /dict }
{ fstream } { /stream }
{ stream } { /stream }
}
/OBJ
}
\use:c { @@_backend_object_write_ #2 :nn } {#1} {#3}
}
\cs_new_protected:Npn \@@_backend_object_write_array:nn #1#2
{
\@@_backend_pdfmark:e
{ #1 ~0~ [ ~ \exp_not:n {#2} ~ ] ~ /PUTINTERVAL }
}
\cs_new_protected:Npn \@@_backend_object_write_dict:nn #1#2
{
\@@_backend_pdfmark:e
{ #1 << \exp_not:n {#2} >> /PUT }
}
\cs_new_protected:Npn \@@_backend_object_write_fstream:nn #1#2
{
\exp_args:Ne
\@@_backend_object_write_fstream:nnn {#1} #2
}
\cs_new_protected:Npn \@@_backend_object_write_fstream:nnn #1#2#3
{
\__kernel_backend_postscript:n
{
SDict ~ begin ~
mark ~ #1 ~ << #2 >> /PUT ~ pdfmark ~
mark ~ #1 ~ ( #3 )~ ( r )~ file ~ /PUT ~ pdfmark ~
end
}
}
\cs_new_protected:Npn \@@_backend_object_write_stream:nn #1#2
{
\exp_args:Ne
\@@_backend_object_write_stream:nnn {#1} #2
}
\cs_new_protected:Npn \@@_backend_object_write_stream:nnn #1#2#3
{
\__kernel_backend_postscript:n
{
mark ~ #1 ~ ( #3 ) /PUT ~ pdfmark ~
mark ~ #1 ~ << #2 >> /PUT ~ pdfmark
}
}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@_backend_object_now:nn, \@@_backend_object_now:ne}
% No anonymous objects, so things are done manually.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_now:nn #1#2
{
\int_gincr:N \g_@@_backend_object_int
\@@_backend_object_write_aux:nnn
{ { pdf.obj \int_use:N \g_@@_backend_object_int } }
{#1} {#2}
}
\cs_generate_variant:Nn \@@_backend_object_now:nn { ne }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_object_last:}
% Much like the annotation version.
% \begin{macrocode}
\cs_new:Npn \@@_backend_object_last:
{ { pdf.obj \int_use:N \g_@@_backend_object_int } }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_pageobject_ref:n}
% Page references are easy in \texttt{dvips}.
% \begin{macrocode}
\cs_new:Npn \@@_backend_pageobject_ref:n #1
{ { Page #1 } }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Destinations}
%
% \begin{macro}{\@@_backend_destination:nn}
% \begin{macro}{\@@_backend_destination:nnnn, \@@_backend_destination_aux:nnnn}
% Here, we need to turn the zoom into a scale. We also need to know where
% the current anchor point actually is: worked out in PostScript. For the
% rectangle version, we have a bit more PostScript: we need two points.
% fitr without rule spec doesn't work, so it falls back to \texttt{/Fit} here.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_destination:nn #1#2
{
\__kernel_backend_postscript:n { pdf.dest.anchor }
\@@_backend_pdfmark:e
{
/View
[
\str_case:nnF {#2}
{
{ xyz } { /XYZ ~ pdf.dest.point ~ null }
{ fit } { /Fit }
{ fitb } { /FitB }
{ fitbh } { /FitBH ~ pdf.dest.y }
{ fitbv } { /FitBV ~ pdf.dest.x }
{ fith } { /FitH ~ pdf.dest.y }
{ fitv } { /FitV ~ pdf.dest.x }
{ fitr } { /Fit }
}
{
/XYZ ~ pdf.dest.point ~ \fp_eval:n { (#2) / 100 }
}
]
/Dest ( \exp_not:n {#1} ) cvn
/DEST
}
}
\cs_new_protected:Npn \@@_backend_destination:nnnn #1#2#3#4
{
\exp_args:Ne \@@_backend_destination_aux:nnnn
{ \dim_eval:n {#2} } {#1} {#3} {#4}
}
\cs_new_protected:Npn \@@_backend_destination_aux:nnnn #1#2#3#4
{
\vbox_to_zero:n
{
\__kernel_kern:n {#4}
\hbox:n { \__kernel_backend_postscript:n { pdf.save.ll } }
\tex_vss:D
}
\__kernel_kern:n {#1}
\vbox_to_zero:n
{
\__kernel_kern:n { -#3 }
\hbox:n { \__kernel_backend_postscript:n { pdf.save.ur } }
\tex_vss:D
}
\__kernel_kern:n { -#1 }
\@@_backend_pdfmark:n
{
/View
[
/FitR ~
pdf.llx ~ pdf.lly ~ pdf.dest2device ~
pdf.urx ~ pdf.ury ~ pdf.dest2device
]
/Dest ( #2 ) cvn
/DEST
}
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsubsection{Structure}
%
% \begin{macro}{\@@_backend_compresslevel:n}
% \begin{macro}{\@@_backend_compress_objects:n}
% Doable for the usual \texttt{ps2pdf} method.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_compresslevel:n #1
{
\int_compare:nNnT {#1} = 0
{
\__kernel_backend_literal_postscript:n
{
/setdistillerparams ~ where
{ pop << /CompressPages ~ false >> setdistillerparams }
if
}
}
}
\cs_new_protected:Npn \@@_backend_compress_objects:n #1
{
\bool_if:nF {#1}
{
\__kernel_backend_literal_postscript:n
{
/setdistillerparams ~ where
{ pop << /CompressStreams ~ false >> setdistillerparams }
if
}
}
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}
% {\@@_backend_version_major_gset:n, \@@_backend_version_minor_gset:n}
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_version_major_gset:n #1
{
\cs_gset:Npe \@@_backend_version_major: { \int_eval:n {#1} }
}
\cs_new_protected:Npn \@@_backend_version_minor_gset:n #1
{
\cs_gset:Npe \@@_backend_version_minor: { \int_eval:n {#1} }
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_version_major:, \@@_backend_version_minor:}
% Data not available!
% \begin{macrocode}
\cs_new:Npn \@@_backend_version_major: { -1 }
\cs_new:Npn \@@_backend_version_minor: { -1 }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Marked content}
%
% \begin{macro}{\@@_backend_bdc:nn}
% \begin{macro}{\@@_backend_emc:}
% Simple wrappers.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_bdc:nn #1#2
{ \@@_backend_pdfmark:n { /#1 ~ #2 /BDC } }
\cs_new_protected:Npn \@@_backend_emc:
{ \@@_backend_pdfmark:n { /EMC } }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macrocode}
%</dvips>
% \end{macrocode}
%
% \subsection{\LuaTeX{} and \pdfTeX{} backend}
%
% \begin{macrocode}
%<*luatex|pdftex>
% \end{macrocode}
%
% \subsubsection{Destinations}
%
% \begin{macro}{\@@_backend_destination:nn}
% \begin{macro}{\@@_backend_destination:nnnn}
% A simple task: pass the data to the primitive. The |\scan_stop:| deals
% with the danger of an unterminated keyword. The zoom given here is a
% percentage, but we need to pass it as \emph{per mille}. The rectangle
% version is also easy as everything is build in.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_destination:nn #1#2
{
%<*luatex>
\tex_pdfextension:D dest ~
%</luatex>
%<*pdftex>
\tex_pdfdest:D
%</pdftex>
name {#1}
\str_case:nnF {#2}
{
{ xyz } { xyz }
{ fit } { fit }
{ fitb } { fitb }
{ fitbh } { fitbh }
{ fitbv } { fitbv }
{ fith } { fith }
{ fitv } { fitv }
{ fitr } { fitr }
}
{ xyz ~ zoom \fp_eval:n { #2 * 10 } }
\scan_stop:
}
\cs_new_protected:Npn \@@_backend_destination:nnnn #1#2#3#4
{
%<*luatex>
\tex_pdfextension:D dest ~
%</luatex>
%<*pdftex>
\tex_pdfdest:D
%</pdftex>
name {#1}
fitr ~
width \dim_eval:n {#2} ~
height \dim_eval:n {#3} ~
depth \dim_eval:n {#4} \scan_stop:
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsubsection{Catalogue entries}
%
% \begin{macro}{\@@_backend_catalog_gput:nn, \@@_backend_info_gput:nn}
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_catalog_gput:nn #1#2
{
%<*luatex>
\tex_pdfextension:D catalog
%</luatex>
%<*pdftex>
\tex_pdfcatalog:D
%</pdftex>
{ / #1 ~ #2 }
}
\cs_new_protected:Npn \@@_backend_info_gput:nn #1#2
{
%<*luatex>
\tex_pdfextension:D info
%</luatex>
%<*pdftex>
\tex_pdfinfo:D
%</pdftex>
{ / #1 ~ #2 }
}
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Objects}
%
% \begin{variable}{\g_@@_backend_object_prop}
% For tracking objects to allow finalisation.
% \begin{macrocode}
\prop_new:N \g_@@_backend_object_prop
% \end{macrocode}
% \end{variable}
%
% \begin{macro}{\@@_backend_object_new:}
% \begin{macro}[EXP]{\@@_backend_object_ref:n, \@@_backend_object_id:n}
% Declaring objects means reserving at the PDF level plus starting
% tracking.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_new:
{
%<*luatex>
\tex_pdfextension:D obj ~
%</luatex>
%<*pdftex>
\tex_pdfobj:D
%</pdftex>
reserveobjnum ~
\int_gset:Nn \g_@@_backend_object_int
%<*luatex>
{ \tex_pdffeedback:D lastobj }
%</luatex>
%<*pdftex>
{ \tex_pdflastobj:D }
%</pdftex>
}
\cs_new:Npn \@@_backend_object_ref:n #1 { #1 ~ 0 ~ R }
\cs_new:Npn \@@_backend_object_id:n #1 {#1}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@_backend_object_write:nnn, \@@_backend_object_write:nne}
% \begin{macro}[EXP]{\@@_backend_object_write:nn}
% \begin{macro}[EXP]{\@@_exp_not_i:nn, \@@_exp_not_ii:nn}
% Writing the data needs a little information about the structure of the
% object.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_write:nnn #1#2#3
{
%<*luatex>
\tex_immediate:D \tex_pdfextension:D obj ~
%</luatex>
%<*pdftex>
\tex_immediate:D \tex_pdfobj:D
%</pdftex>
useobjnum ~ #1
\@@_backend_object_write:nn {#2} {#3}
}
\cs_new:Npn \@@_backend_object_write:nn #1#2
{
\str_case:nn {#1}
{
{ array } { { [ ~ \exp_not:n {#2} ~ ] } }
{ dict } { { << ~ \exp_not:n {#2} ~ >> } }
{ fstream }
{
stream ~ attr ~ { \@@_exp_not_i:nn #2 } ~
file ~ { \@@_exp_not_ii:nn #2 }
}
{ stream }
{
stream ~ attr ~ { \@@_exp_not_i:nn #2 } ~
{ \@@_exp_not_ii:nn #2 }
}
}
}
\cs_generate_variant:Nn \@@_backend_object_write:nnn { nne }
\cs_new:Npn \@@_exp_not_i:nn #1#2 { \exp_not:n {#1} }
\cs_new:Npn \@@_exp_not_ii:nn #1#2 { \exp_not:n {#2} }
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@_backend_object_now:nn, \@@_backend_object_now:ne}
% Much like writing, but direct creation.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_now:nn #1#2
{
%<*luatex>
\tex_immediate:D \tex_pdfextension:D obj ~
%</luatex>
%<*pdftex>
\tex_immediate:D \tex_pdfobj:D
%</pdftex>
\@@_backend_object_write:nn {#1} {#2}
}
\cs_generate_variant:Nn \@@_backend_object_now:nn { ne }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_object_last:}
% Much like annotation.
% \begin{macrocode}
\cs_new:Npe \@@_backend_object_last:
{
\exp_not:N \int_value:w
%<*luatex>
\exp_not:N \tex_pdffeedback:D lastobj ~
%</luatex>
%<*pdftex>
\exp_not:N \tex_pdflastobj:D
%</pdftex>
\c_space_tl 0 ~ R
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_pageobject_ref:n}
% The usual wrapper situation; the three spaces here are essential.
% \begin{macrocode}
\cs_new:Npe \@@_backend_pageobject_ref:n #1
{
\exp_not:N \int_value:w
%<*luatex>
\exp_not:N \tex_pdffeedback:D pageref
%</luatex>
%<*pdftex>
\exp_not:N \tex_pdfpageref:D
%</pdftex>
\c_space_tl #1 \c_space_tl \c_space_tl \c_space_tl 0 ~ R
}
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Structure}
%
% \begin{macro}{\@@_backend_compresslevel:n}
% \begin{macro}{\@@_backend_compress_objects:n}
% \begin{macro}{\@@_backend_objcompresslevel:n}
% Simply pass data to the engine.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_compresslevel:n #1
{
\tex_global:D
%<*luatex>
\tex_pdfvariable:D compresslevel
%</luatex>
%<*pdftex>
\tex_pdfcompresslevel:D
%</pdftex>
\int_value:w \int_eval:n {#1} \scan_stop:
}
\cs_new_protected:Npn \@@_backend_compress_objects:n #1
{
\bool_if:nTF {#1}
{ \@@_backend_objcompresslevel:n { 2 } }
{ \@@_backend_objcompresslevel:n { 0 } }
}
\cs_new_protected:Npn \@@_backend_objcompresslevel:n #1
{
\tex_global:D
%<*luatex>
\tex_pdfvariable:D objcompresslevel
%</luatex>
%<*pdftex>
\tex_pdfobjcompresslevel:D
%</pdftex>
#1 \scan_stop:
}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}
% {\@@_backend_version_major_gset:n, \@@_backend_version_minor_gset:n}
% The availability of the primitive is not universal, so we have to test
% at load time.
% \begin{macrocode}
\cs_new_protected:Npe \@@_backend_version_major_gset:n #1
{
%<*luatex>
\int_compare:nNnT \tex_luatexversion:D > { 106 }
{
\exp_not:N \tex_global:D \tex_pdfvariable:D majorversion
\exp_not:N \int_eval:n {#1} \scan_stop:
}
%</luatex>
%<*pdftex>
\cs_if_exist:NT \tex_pdfmajorversion:D
{
\exp_not:N \tex_global:D \tex_pdfmajorversion:D
\exp_not:N \int_eval:n {#1} \scan_stop:
}
%</pdftex>
}
\cs_new_protected:Npn \@@_backend_version_minor_gset:n #1
{
\tex_global:D
%<*luatex>
\tex_pdfvariable:D minorversion
%</luatex>
%<*pdftex>
\tex_pdfminorversion:D
%</pdftex>
\int_eval:n {#1} \scan_stop:
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_version_major:, \@@_backend_version_minor:}
% As above.
% \begin{macrocode}
\cs_new:Npe \@@_backend_version_major:
{
%<*luatex>
\int_compare:nNnTF \tex_luatexversion:D > { 106 }
{ \exp_not:N \tex_the:D \tex_pdfvariable:D majorversion }
{ 1 }
%</luatex>
%<*pdftex>
\cs_if_exist:NTF \tex_pdfmajorversion:D
{ \exp_not:N \tex_the:D \tex_pdfmajorversion:D }
{ 1 }
%</pdftex>
}
\cs_new:Npn \@@_backend_version_minor:
{
\tex_the:D
%<*luatex>
\tex_pdfvariable:D minorversion
%</luatex>
%<*pdftex>
\tex_pdfminorversion:D
%</pdftex>
}
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Marked content}
%
% \begin{macro}{\@@_backend_bdc:nn}
% \begin{macro}{\@@_backend_emc:}
% Simple wrappers. May need refinement: see
% \url{https://chat.stackexchange.com/transcript/message/49970158#49970158}.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_bdc:nn #1#2
{ \__kernel_backend_literal_page:n { /#1 ~ #2 ~ BDC } }
\cs_new_protected:Npn \@@_backend_emc:
{ \__kernel_backend_literal_page:n { EMC } }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macrocode}
%</luatex|pdftex>
% \end{macrocode}
%
% \subsection{\texttt{dvipdfmx} backend}
%
% \begin{macrocode}
%<*dvipdfmx|xetex>
% \end{macrocode}
%
% \begin{macro}{\@@_backend:n, \@@_backend:e}
% A generic function for the backend PDF specials: used where we can.
% \begin{macrocode}
\cs_new_protected:Npe \@@_backend:n #1
{ \__kernel_backend_literal:n { pdf: #1 } }
\cs_generate_variant:Nn \@@_backend:n { e }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Catalogue entries}
%
% \begin{macro}{\@@_backend_catalog_gput:nn, \@@_backend_info_gput:nn}
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_catalog_gput:nn #1#2
{ \@@_backend:n { put ~ @catalog << /#1 ~ #2 >> } }
\cs_new_protected:Npn \@@_backend_info_gput:nn #1#2
{ \@@_backend:n { docinfo << /#1 ~ #2 >> } }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Objects}
%
% \begin{variable}{\g_@@_backend_object_prop}
% For tracking objects to allow finalisation.
% \begin{macrocode}
\prop_new:N \g_@@_backend_object_prop
% \end{macrocode}
% \end{variable}
%
% \begin{macro}{\@@_backend_object_new:}
% \begin{macro}[EXP]{\@@_backend_object_ref:n, \@@_backend_object_id:n}
% Objects are tracked at the macro level, but we don't have to do anything
% at this stage.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_new:
{ \int_gincr:N \g_@@_backend_object_int }
\cs_new:Npn \@@_backend_object_ref:n #1 { @pdf.obj #1 }
\cs_new_eq:NN \@@_backend_object_id:n \@@_backend_object_ref:n
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@_backend_object_write:nnn, \@@_backend_object_write:nne}
% \begin{macro}
% {
% \@@_backend_object_write_array:nn ,
% \@@_backend_object_write_dict:nn ,
% \@@_backend_object_write_fstream:nn ,
% \@@_backend_object_write_stream:nn
% }
% \begin{macro}{\@@_backend_object_write_stream:nnnn}
% This is where we choose the actual type.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_write:nnn #1#2#3
{
\use:c { @@_backend_object_write_ #2 :nn }
{ \@@_backend_object_ref:n {#1} } {#3}
}
\cs_generate_variant:Nn \@@_backend_object_write:nnn { nne }
\cs_new_protected:Npn \@@_backend_object_write_array:nn #1#2
{
\@@_backend:e
{ obj ~ #1 ~ [ ~ \exp_not:n {#2} ~ ] }
}
\cs_new_protected:Npn \@@_backend_object_write_dict:nn #1#2
{
\@@_backend:e
{ obj ~ #1 ~ << ~ \exp_not:n {#2} ~ >> }
}
\cs_new_protected:Npn \@@_backend_object_write_fstream:nn #1#2
{ \@@_backend_object_write_stream:nnnn { f } {#1} #2 }
\cs_new_protected:Npn \@@_backend_object_write_stream:nn #1#2
{ \@@_backend_object_write_stream:nnnn { } {#1} #2 }
\cs_new_protected:Npn \@@_backend_object_write_stream:nnnn #1#2#3#4
{
\@@_backend:e
{
#1 stream ~ #2 ~
( \exp_not:n {#4} ) ~ << \exp_not:n {#3} >>
}
}
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \begin{macro}{\@@_backend_object_now:nn, \@@_backend_object_now:ne}
% No anonymous objects with \texttt{dvipdfmx} so we have to give an
% object name.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_now:nn #1#2
{
\int_gincr:N \g_@@_backend_object_int
\exp_args:Nne \use:c { @@_backend_object_write_ #1 :nn }
{ @pdf.obj \int_use:N \g_@@_backend_object_int }
{#2}
}
\cs_generate_variant:Nn \@@_backend_object_now:nn { ne }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_backend_object_last:}
% \begin{macrocode}
\cs_new:Npn \@@_backend_object_last:
{ @pdf.obj \int_use:N \g_@@_backend_object_int }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_pageobject_ref:n}
% Page references are easy in \texttt{dvipdfmx}/\XeTeX{}.
% \begin{macrocode}
\cs_new:Npn \@@_backend_pageobject_ref:n #1
{ @page #1 }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Destinations}
%
% \begin{macro}{\@@_backend_destination:nn}
% \begin{macro}{\@@_backend_destination:nnnn,\@@_backend_destination_aux:nnnn}
% Here, we need to turn the zoom into a scale. The method for \texttt{FitR}
% is from Alexander Grahn: the idea is to avoid needing to do any calculations
% in \TeX{} by using the backend data for \texttt{@xpos} and \texttt{@ypos}.
% \texttt{/FitR} without rule spec doesn't work, so it falls back to
% \texttt{/Fit} here.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_destination:nn #1#2
{
\@@_backend:e
{
dest ~ ( \exp_not:n {#1} )
[
@thispage
\str_case:nnF {#2}
{
{ xyz } { /XYZ ~ @xpos ~ @ypos ~ null }
{ fit } { /Fit }
{ fitb } { /FitB }
{ fitbh } { /FitBH }
{ fitbv } { /FitBV ~ @xpos }
{ fith } { /FitH ~ @ypos }
{ fitv } { /FitV ~ @xpos }
{ fitr } { /Fit }
}
{ /XYZ ~ @xpos ~ @ypos ~ \fp_eval:n { (#2) / 100 } }
]
}
}
\cs_new_protected:Npn \@@_backend_destination:nnnn #1#2#3#4
{
\exp_args:Ne \@@_backend_destination_aux:nnnn
{ \dim_eval:n {#2} } {#1} {#3} {#4}
}
\cs_new_protected:Npn \@@_backend_destination_aux:nnnn #1#2#3#4
{
\vbox_to_zero:n
{
\__kernel_kern:n {#4}
\hbox:n
{
\@@_backend:n { obj ~ @pdf_ #2 _llx ~ @xpos }
\@@_backend:n { obj ~ @pdf_ #2 _lly ~ @ypos }
}
\tex_vss:D
}
\__kernel_kern:n {#1}
\vbox_to_zero:n
{
\__kernel_kern:n { -#3 }
\hbox:n
{
\@@_backend:n
{
dest ~ (#2)
[
@thispage
/FitR ~
@pdf_ #2 _llx ~ @pdf_ #2 _lly ~
@xpos ~ @ypos
]
}
}
\tex_vss:D
}
\__kernel_kern:n { -#1 }
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsubsection{Structure}
%
% \begin{macro}{\@@_backend_compresslevel:n}
% \begin{macro}{\@@_backend_compress_objects:n}
% Pass data to the backend: these are a one-shot.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_compresslevel:n #1
{ \__kernel_backend_literal:e { dvipdfmx:config~z~ \int_eval:n {#1} } }
\cs_new_protected:Npn \@@_backend_compress_objects:n #1
{
\bool_if:nF {#1}
{ \__kernel_backend_literal:n { dvipdfmx:config~C~0x40 } }
}
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}
% {\@@_backend_version_major_gset:n, \@@_backend_version_minor_gset:n}
% We start with the assumption that the default is active.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_version_major_gset:n #1
{
\cs_gset:Npe \@@_backend_version_major: { \int_eval:n {#1} }
\__kernel_backend_literal:e { pdf:majorversion~ \@@_backend_version_major: }
}
\cs_new_protected:Npn \@@_backend_version_minor_gset:n #1
{
\cs_gset:Npe \@@_backend_version_minor: { \int_eval:n {#1} }
\__kernel_backend_literal:e { pdf:minorversion~ \@@_backend_version_minor: }
}
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_version_major:, \@@_backend_version_minor:}
% We start with the assumption that the default is active.
% \begin{macrocode}
\cs_new:Npn \@@_backend_version_major: { 1 }
\cs_new:Npn \@@_backend_version_minor: { 5 }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Marked content}
%
% \begin{macro}{\@@_backend_bdc:nn}
% \begin{macro}{\@@_backend_emc:}
% Simple wrappers. May need refinement: see
% \url{https://chat.stackexchange.com/transcript/message/49970158#49970158}.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_bdc:nn #1#2
{ \__kernel_backend_literal_page:n { /#1 ~ #2 ~ BDC } }
\cs_new_protected:Npn \@@_backend_emc:
{ \__kernel_backend_literal_page:n { EMC } }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macrocode}
%</dvipdfmx|xetex>
% \end{macrocode}
%
% \subsection{\texttt{dvisvgm} backend}
%
% \begin{macrocode}
%<*dvisvgm>
% \end{macrocode}
%
% \subsubsection{Destinations}
%
% \begin{macro}{\@@_backend_destination:nn}
% \begin{macro}{\@@_backend_destination:nnnn}
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_destination:nn #1#2 { }
\cs_new_protected:Npn \@@_backend_destination:nnnn #1#2#3#4 { }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \subsubsection{Catalogue entries}
%
% \begin{macro}{\@@_backend_catalog_gput:nn, \@@_backend_info_gput:nn}
% No-op.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_catalog_gput:nn #1#2 { }
\cs_new_protected:Npn \@@_backend_info_gput:nn #1#2 { }
% \end{macrocode}
% \end{macro}
%
% \subsubsection{Objects}
%
% \begin{macro}{\@@_backend_object_new:}
% \begin{macro}[EXP]{\@@_backend_object_ref:n, \@@_backend_object_id:n}
% \begin{macro}{\@@_backend_object_write:nnn, \@@_backend_object_write:ne}
% \begin{macro}{\@@_backend_object_now:nn, , \@@_backend_object_now:ne}
% \begin{macro}{\@@_backend_object_last:}
% \begin{macro}[EXP]{\@@_backend_pageobject_ref:n}
% All no-ops here.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_object_new: { }
\cs_new:Npn \@@_backend_object_ref:n #1 { }
\cs_new:Npn \@@_backend_object_id:n #1 { }
\cs_new_protected:Npn \@@_backend_object_write:nnn #1#2#3 { }
\cs_new_protected:Npn \@@_backend_object_write:nne #1#2#3 { }
\cs_new_protected:Npn \@@_backend_object_now:nn #1#2 { }
\cs_new_protected:Npn \@@_backend_object_now:ne #1#2 { }
\cs_new:Npn \@@_backend_object_last: { }
\cs_new:Npn \@@_backend_pageobject_ref:n #1 { }
% \end{macrocode}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
% \end{macro}
%
% \subsubsection{Structure}
%
% \begin{macro}{\@@_backend_compresslevel:n}
% \begin{macro}{\@@_backend_compress_objects:n}
% These are all no-ops.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_compresslevel:n #1 { }
\cs_new_protected:Npn \@@_backend_compress_objects:n #1 { }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macro}
% {\@@_backend_version_major_gset:n, \@@_backend_version_minor_gset:n}
% Data not available!
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_version_major_gset:n #1 { }
\cs_new_protected:Npn \@@_backend_version_minor_gset:n #1 { }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}[EXP]{\@@_backend_version_major:, \@@_backend_version_minor:}
% Data not available!
% \begin{macrocode}
\cs_new:Npn \@@_backend_version_major: { -1 }
\cs_new:Npn \@@_backend_version_minor: { -1 }
% \end{macrocode}
% \end{macro}
%
% \begin{macro}{\@@_backend_bdc:nn}
% \begin{macro}{\@@_backend_emc:}
% More no-ops.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_bdc:nn #1#2 { }
\cs_new_protected:Npn \@@_backend_emc: { }
% \end{macrocode}
% \end{macro}
% \end{macro}
%
% \begin{macrocode}
%</dvisvgm>
% \end{macrocode}
%
% \subsection{PDF Page size (media box)}
%
% For setting the media box, the split between backends is somewhat different
% to other areas, thus we approach this separately. The code here assumes a
% recent \LaTeXe{}: that is ensured at the level above.
%
% \begin{macrocode}
%<*dvipdfmx|dvips>
% \end{macrocode}
%
% \begin{macro}{\@@_backend_pagesize_gset:nn}
% This is done as a backend literal, so we deal with it using the shipout
% hook.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_pagesize_gset:nn #1#2
{
\__kernel_backend_first_shipout:n
{
\__kernel_backend_literal:e
{
%<*dvipdfmx>
pdf:pagesize ~
width ~ \dim_eval:n {#1} ~
height ~ \dim_eval:n {#2}
%</dvipdfmx>
%<*dvips>
papersize = \dim_eval:n {#1} , \dim_eval:n {#2}
%</dvips>
}
}
}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</dvipdfmx|dvips>
% \end{macrocode}
%
% \begin{macrocode}
%<*luatex|pdftex|xetex>
% \end{macrocode}
%
% \begin{macro}{\@@_backend_pagesize_gset:nn}
% Pass to the primitives.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_pagesize_gset:nn #1#2
{
\dim_gset:Nn \tex_pagewidth:D {#1}
\dim_gset:Nn \tex_pageheight:D {#2}
}
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</luatex|pdftex|xetex>
% \end{macrocode}
%
% \begin{macrocode}
%<*dvisvgm>
% \end{macrocode}
%
% \begin{macro}{\@@_backend_pagesize_gset:nn}
% A no-op.
% \begin{macrocode}
\cs_new_protected:Npn \@@_backend_pagesize_gset:nn #1#2 { }
% \end{macrocode}
% \end{macro}
%
% \begin{macrocode}
%</dvisvgm>
% \end{macrocode}
%
% \begin{macrocode}
%</package>
% \end{macrocode}
%
% \end{implementation}
%
% \PrintIndex