%D \module
%D   [       file=back-pdf,
%D        version=2009.04.15,
%D          title=\CONTEXT\ Backend Macros,
%D       subtitle=\PDF,
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA ADE \& \CONTEXT\ Development Team}]
%C
%C This module is part of the \CONTEXT\ macro||package and is
%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
%C details.

\writestatus{loading}{ConTeXt Backend Macros / PDF}

%registerctxluafile{lpdf-aux}{1.001} % common helpers
\registerctxluafile{lpdf-ini}{1.001}
\registerctxluafile{lpdf-nod}{1.001}
\registerctxluafile{lpdf-col}{1.000}
\registerctxluafile{lpdf-xmp}{1.001}
\registerctxluafile{lpdf-ano}{1.001}
\registerctxluafile{lpdf-res}{1.001}
\registerctxluafile{lpdf-mis}{1.001}
\registerctxluafile{lpdf-ren}{1.001}
\registerctxluafile{lpdf-grp}{1.001}
\registerctxluafile{lpdf-wid}{1.001}
\registerctxluafile{lpdf-fld}{1.001}
\registerctxluafile{lpdf-mov}{1.001}
\registerctxluafile{lpdf-u3d}{1.001}
\registerctxluafile{lpdf-swf}{1.001}
\registerctxluafile{lpdf-tag}{1.001}
\registerctxluafile{lpdf-fmt}{1.001}
\registerctxluafile{lpdf-epd}{1.001}
\registerctxluafile{lpdf-epa}{1.001}

\registerctxluafile{back-pdf}{1.001} % some code will move to lpdf-*

\unprotect

%D We will minimize the number of calls to \PDF\ specific primitives
%D and delegate all management and injection of code to the backend.
%D
%D Here we initialize some internal quantities. We also protect them.

\outputmode\plusone  \let\outputmode\relax  \newcount\outputmode  \outputmode\plusone

%D Because we do a lot in \LUA\ and don't want interferences, we nil most of the
%D \PDFTEX\ primitives. Of course one can always use the \type {\pdfvariable},
%D \type {\pdfextension} and \type {\pdffeedback} primitives but it will probably
%D have bad side effects.

%D These are no-ops and don't even intercept what comes next. Maybe some day
%D I'll write a parser that maps onto \CONTEXT.

\unexpanded\def\unsupportedpdfprimitive#1%
  {\writestatus{error}{the primitive \string#1\space is not supported}}

\unexpanded\def\pdfcolorstack    {\unsupportedpdfprimitive\pdfcolorstack}
\unexpanded\def\pdfcolorstackinit{\unsupportedpdfprimitive\pdfcolorstackinit}
%unexpanded\def\pdfannot         {\unsupportedpdfprimitive\pdfannot}
\unexpanded\def\pdfstartlink     {\unsupportedpdfprimitive\pdfstartlink}
\unexpanded\def\pdfendlink       {\unsupportedpdfprimitive\pdfendlink}
\unexpanded\def\pdfoutline       {\unsupportedpdfprimitive\pdfoutline}
%unexpanded\def\pdfdest          {\unsupportedpdfprimitive\pdfdest}
\unexpanded\def\pdfthread        {\unsupportedpdfprimitive\pdfthread}
\unexpanded\def\pdfstartthread   {\unsupportedpdfprimitive\pdfstartthread}
\unexpanded\def\pdfendthread     {\unsupportedpdfprimitive\pdfendthread}
\unexpanded\def\pdffontattr      {\unsupportedpdfprimitive\pdffontattr}
\unexpanded\def\pdfglyphtounicode{\unsupportedpdfprimitive\pdfglyphtounicode}

\unexpanded\def\pdfannot{\clf_pdfannot}
\unexpanded\def\pdfdest {\clf_pdfdest}

%D Here we do intercept (silently) what gets passed. One should use the
%D \CONTEXT\ interfaces instead.

\let\pdfcatalog       \relax  \newtoks\pdfcatalog
\let\pdfinfo          \relax  \newtoks\pdfinfo
\let\pdfnames         \relax  \newtoks\pdfnames
\let\pdftrailer       \relax  \newtoks\pdftrailer
\let\pdfpageresources \relax  \newtoks\pdfpageresources
\let\pdfpageattr      \relax  \newtoks\pdfpageattr
\let\pdfpagesattr     \relax  \newtoks\pdfpagesattr
\let\pdfxformattr     \relax  \newtoks\pdfxformattr
\let\pdfxformresources\relax  \newtoks\pdfxformresources

%D We use the \LUA\ interface (which then permits more control over
%D possible pdf/x extensions).

\let\pdfcompresslevel   \relax  \newcount\pdfcompresslevel
\let\pdfobjcompresslevel\relax  \newcount\pdfobjcompresslevel

%D But we still provide:

\unexpanded\def\nopdfcompression      {\clf_setpdfcompression\zerocount\zerocount}
\unexpanded\def\maximumpdfcompression {\clf_setpdfcompression\plusnine \plusnine }
\unexpanded\def\normalpdfcompression  {\clf_setpdfcompression\plusthree\plusthree}

%D These might even become no-ops as we don't need them in \CONTEXT:

\unexpanded\def\pdfmapfile#1{\clf_setmapfile{#1}}
\unexpanded\def\pdfmapline#1{\clf_setmapline{#1}}

%D We don't support these directives, at least not this way. If they are needed
%D by third party modules we can provide some interface.

\let\pdfcreationdate           \relax \newtoks \pdfcreationdate
\let\pdfdecimaldigits          \relax \newcount\pdfdecimaldigits
\let\pdfdestmargin             \relax \newcount\pdfdestmargin
\let\pdffontname               \relax \newcount\pdffontname
\let\pdffontobjnum             \relax \newcount\pdffontobjnum
\let\pdffontsize               \relax \newcount\pdffontsize
\let\pdfgamma                  \relax \newcount\pdfgamma
\let\pdfgentounicode           \relax \newcount\pdfgentounicode
\let\pdfhorigin                \relax \newcount\pdfhorigin
\let\pdfignoreunknownimages    \relax \newcount\pdfignoreunknownimages
\let\pdfimageaddfilename       \relax \newcount\pdfimageaddfilename
\let\pdfimageapplygamma        \relax \newcount\pdfimageapplygamma
\let\pdfimagegamma             \relax \newcount\pdfimagegamma
\let\pdfimagehicolor           \relax \newcount\pdfimagehicolor
\let\pdfimageresolution        \relax \newcount\pdfimageresolution
\let\pdfincludechars           \relax \newtoks \pdfincludechars
\let\pdfinclusioncopyfonts     \relax \newcount\pdfinclusioncopyfonts
\let\pdfinclusionerrorlevel    \relax \newcount\pdfinclusionerrorlevel
\let\pdfinfoomitdate           \relax \newcount\pdfinfoomitdate
\let\pdflastannot              \relax \newcount\pdflastannot
\let\pdflastlink               \relax \newcount\pdflastlink
\let\pdflinkmargin             \relax \newcount\pdflinkmargin
\let\pdfminorversion           \relax \newcount\pdfminorversion
\let\pdfpagebox                \relax \newcount\pdfpagebox
\let\pdfpageref                \relax \newcount\pdfpageref
\let\pdfpkfixeddpi             \relax \newcount\pdfpkfixeddpi
\let\pdfpkmode                 \relax \newtoks \pdfpkmode
\let\pdfpkresolution           \relax \newcount\pdfpkresolution
\let\pdfretval                 \relax \newcount\pdfretval
\let\pdfsuppressoptionalinfo   \relax \newcount\pdfsuppressoptionalinfo
\let\pdfsuppressptexinfo       \relax \newcount\pdfsuppressptexinfo
\let\pdftexrevision            \relax \newcount\pdftexrevision
\let\pdftexversion             \relax \newcount\pdftexversion
\let\pdfthreadmargin           \relax \newcount\pdfthreadmargin
\let\pdftrailerid              \relax \newtoks \pdftrailerid
\let\pdfuniqueresname          \relax \newcount\pdfuniqueresname
\let\pdfvorigin                \relax \newcount\pdfvorigin
\let\pdfxformmargin            \relax \newcount\pdfxformmargin
\let\pdfxformname              \relax \newcount\pdfxformname

%D These are still accepted but are normally not needed.

\let\pdflastxform              \lastsavedboxresourceindex
\let\pdflastximage             \lastsavedimageresourceindex
\let\pdflastximagepages        \lastsavedimageresourcepages
\let\pdflastxpos               \lastxpos
\let\pdflastypos               \lastypos
\let\pdfrefxform               \useboxresource
\let\pdfrefximage              \useimageresource
\let\pdfsavepos                \savepos
\let\pdfxform                  \saveboxresource
\let\pdfximage                 \saveimageresource

%D For the moment we keep these as they are but they will become \LUA\
%D calls eventually, after which we will nil the three \type {\pdf}
%D interface primitives.

\normalprotected\def\pdfliteral  {\pdfextension literal }
\normalprotected\def\pdfobj      {\pdfextension obj }
                \def\pdflastobj  {\numexpr\pdffeedback  lastobj\relax}
\normalprotected\def\pdfrefobj   {\pdfextension refobj }
\normalprotected\def\pdfrestore  {\pdfextension restore\relax}
\normalprotected\def\pdfsave     {\pdfextension save\relax}
\normalprotected\def\pdfsetmatrix{\pdfextension setmatrix }

%D This one can be consulted by users although the suffix is also
%D a system mode.

\back_job_set_suffix{pdf}

%D PDF/X (maybe combine the two lua calls)

\setupbackend
  [xmpfile=]

\appendtoks
    \doifsomething{\backendparameter{xmpfile}}
      {\clf_setxmpfile{\backendparameter{xmpfile}}}%
\to \everysetupbackend

% \doifsomething{\backendparameter\c!format} .. at the lua end

\appendtoks
    \clf_setformat
         format  {\backendparameter\c!format}%
         level   {\backendparameter\c!level}%
         option  {\backendparameter\c!option}%
         profile {\backendparameter\c!profile}%
         intent  {\backendparameter\c!intent}%
         file    {\backendparameter\c!file}%
    \relax
\to \everysetupbackend

%D For the moment we keep these.

%newtoks \pdfbackendeveryximage
\newtoks \pdfbackendeveryxform

%D These are the only official methods to add stuff to the resources.

\unexpanded\def\pdfbackendsetcatalog       #1#2{\clf_lpdf_addtocatalog        {#1}{#2}}
\unexpanded\def\pdfbackendsetinfo          #1#2{\clf_lpdf_addtoinfo           {#1}{#2}}
\unexpanded\def\pdfbackendsetname          #1#2{\clf_lpdf_addtonames          {#1}{#2}}

\unexpanded\def\pdfbackendsetpageattribute #1#2{\clf_lpdf_addtopageattributes  {#1}{#2}}
\unexpanded\def\pdfbackendsetpagesattribute#1#2{\clf_lpdf_addtopagesattributes {#1}{#2}}
\unexpanded\def\pdfbackendsetpageresource  #1#2{\clf_lpdf_addtopageresources   {#1}{#2}}

\unexpanded\def\pdfbackendsetextgstate     #1#2{\clf_lpdf_adddocumentextgstate {#1}{#2}}
\unexpanded\def\pdfbackendsetcolorspace    #1#2{\clf_lpdf_adddocumentcolorspace{#1}{#2}}
\unexpanded\def\pdfbackendsetpattern       #1#2{\clf_lpdf_adddocumentpattern   {#1}{#2}}
\unexpanded\def\pdfbackendsetshade         #1#2{\clf_lpdf_adddocumentshade     {#1}{#2}}

           \def\pdfbackendcurrentresources     {\clf_lpdf_collectedresources}
           \def\pdfcolor                     #1{\clf_lpdf_color\numexpr\thecolorattribute{#1}\relax}
           \let\PDFcolor\pdfcolor

%D Transformations

% rotation

\unexpanded\def\dostartrotation#1%
  {\forcecolorhack
   \clf_pdfstartrotation#1\relax} % todo: implement without Q q

\unexpanded\def\dostoprotation
  {\clf_pdfstoprotation
   \forcecolorhack}

% scaling

\unexpanded\def\dostartscaling#1#2%
  {\forcecolorhack
   \clf_pdfstartscaling rx #1 ry #2\relax}

\unexpanded\def\dostopscaling
  {\clf_pdfstopscaling
   \forcecolorhack}

% mirroring

\unexpanded\def\dostartmirroring
  {\clf_pdfstartmirroring}

\unexpanded\def\dostopmirroring
  {\clf_pdfstopmirroring}

% transform

\unexpanded\def\dotransformnextbox#1#2#3#4#5#6%
  {\dowithnextbox{\dodotransformnextbox{#1}{#2}{#3}{#4}{#5}{#6}}}

\unexpanded\def\dodotransformnextbox#1#2#3#4#5#6%
  {\hpack
     {\kern #5\onebasepoint
      \raise#6\onebasepoint
      \hpack
        {\clf_pdfstartmatrix rx #1 sx #2 sy #3 ry #4\relax
         \box\nextbox
         \clf_pdfstopmatrix}}}

% somehow the shift is not happening .. bug in luatex?
%
% \unexpanded\def\dodotransformnextbox#1#2#3#4#5#6%
%   {\ctxcommand{pdftransformbox(\number\nextbox,#1,#2,#3,#4,\number\dimexpr#5\onebasepoint,\number\dimexpr#6\onebasepoint)}%
%    \box\nextbox}
%
% \startluacode
%     function commands.pdftransformbox(box,rx,sx,sy,ry,tx,ty)
%         if rx == 1 and sx == 0 and sy == 0 and ry == 1 then
%             if tx == 0 and ty == 0 then
%                 local b = nodes.hpack(nodes.concat {
%                     nodes.pool.kern(tx),
%                     nodes.takebox(box),
%                 })
%                 b.shift = -ty
%                 tex.setbox(box,b)
%             else
%                 -- no need to transform
%             end
%         else
%             local b = nodes.hpack(nodes.concat {
%                 nodes.pool.kern(tx),
%                 nodes.pool.pdfsave(),
%                 nodes.pool.pdfsetmatrix(rx,sx,sy,ry),
%                 nodes.takebox(box),
%                 nodes.pool.pdfsetmatrix(-rx,-sx,-sy,-ry),
%                 nodes.pool.pdfrestore(),
%             })
%             b.shift = -ty
%             tex.setbox(box,b)
%         end
%     end
% \stopluacode

% clipping

\unexpanded\def\dostartclipping#1#2#3% we can move this to lua and only set a box here
  {\forcecolorhack
   \PointsToBigPoints{#2}\width
   \PointsToBigPoints{#3}\height
   \meta_grab_clip_path{#1}\width\height{%
     0            0             m %
     \width\space 0             l %
     \width\space \height\space l %
     0            \height\space l%
   }%
   \pdfliteral{q 0 w \MPclippath\space W n}}

\unexpanded\def\dostopclipping
  {\pdfliteral{Q}}

%D Temporary hack, will be removed or improved or default.

% attr {/Group << /S /Transparency /I false /K true >>}

%def\TransparencyHack{\ctxlua{backends.codeinjections.addtransparencygroup()}}
\def\TransparencyHack{\setupcolors[\c!pagecolormodel=\v!auto]}

% \let\lastpredefinedsymbol\empty % some day we can do more at the lua end
%
% \unexpanded\def\predefinesymbol[#1]%
%   {\begingroup
%    \xdef\lastpredefinedsymbol{#1}%
%    \settightobject{SYM}{#1}\hbox{\symbol[#1]}% to be checked ... maybe only fitting
%    \dogetobjectreference{SYM}{#1}\m_back_object_reference
%    \clf_registerbackendsymbol{#1}\m_back_object_reference\relax
%    \endgroup}

% Still here:

%D \macros
%D  {back_ovalbox}
%D
%D Drawing frames with round corners is inherited from the
%D main module.
%D
%D For drawing ovals we use quite raw \PDF\ code. The next
%D implementation does not differ that much from the one
%D implemented in the \POSTSCRIPT\ driver. This code is
%D somewhat obsolete as we now have metapost embedded.

% \def\back_oval_calculate#1#2#3%
%   {\PointsToBigPoints{\dimexpr#2+#3\relax}#1}

\unexpanded\def\back_ovalbox#1#2#3#4#5#6#7#8%
  {\forcecolorhack
   \bgroup
%    \scratchdimen#4%
%    \divide\scratchdimen\plustwo
%    \back_oval_calculate\xmin  \zeropoint\scratchdimen
%    \back_oval_calculate\xmax  {#1}{-\scratchdimen}%
%    \back_oval_calculate\ymax  {#2}{-\scratchdimen}%
%    \back_oval_calculate\ymin  {-#3}\scratchdimen
%    \advance\scratchdimen by #5%
%    \back_oval_calculate\xxmin \zeropoint\scratchdimen
%    \back_oval_calculate\xxmax {#1}{-\scratchdimen}%
%    \back_oval_calculate\yymax {#2}{-\scratchdimen}%
%    \back_oval_calculate\yymin {-#3}\scratchdimen
%    \back_oval_calculate\stroke{#4}\zeropoint
%    \back_oval_calculate\radius{#5}\zeropoint
   %
   \PointsToBigPoints{#4}                       \stroke
   \PointsToBigPoints{#5}                       \radius
   \scratchdimen\dimexpr#4/\plustwo\relax
   \PointsToBigPoints             \scratchdimen \xmin
   \PointsToBigPoints{\dimexpr #1-\scratchdimen}\xmax
   \PointsToBigPoints{\dimexpr #2-\scratchdimen}\ymax
   \PointsToBigPoints{\dimexpr-#3+\scratchdimen}\ymin
   \advance\scratchdimen by #5\relax
   \PointsToBigPoints             \scratchdimen \xxmin
   \PointsToBigPoints{\dimexpr #1-\scratchdimen}\xxmax
   \PointsToBigPoints{\dimexpr #2-\scratchdimen}\yymax
   \PointsToBigPoints{\dimexpr-#3+\scratchdimen}\yymin
   %
   \edef\dostroke{\number#6}%
   \edef\dofill{\number#7}%
   \edef\mode{\number#8}%
   % no \ifcase, else \relax in pdfcode
   \setbox\scratchbox\naturalhpack
     {\ifnum\dostroke\dofill>\zerocount
        \pdfliteral
          {q
           \stroke\space               w
           \ifcase\mode\space
             \xxmin\space \ymin \space m
             \xxmax\space \ymin \space l
             \xmax \space \ymin \space \xmax \space \yymin\space y
             \xmax \space \yymax\space l
             \xmax \space \ymax \space \xxmax\space \ymax \space y
             \xxmin\space \ymax \space l
             \xmin \space \ymax \space \xmin \space \yymax\space y
             \xmin \space \yymin\space l
             \xmin \space \ymin \space \xxmin\space \ymin \space y
             h
           \or % 1
             \xxmin\space \ymin \space m
             \xxmax\space \ymin \space l
             \xmax \space \ymin \space \xmax \space \yymin\space y
             \xmax \space \ymax \space l
             \xmin \space \ymax \space l
             \xmin \space \yymin\space l
             \xmin \space \ymin \space \xxmin\space \ymin \space y
             h
           \or % 2
             \xxmin\space \ymin \space m
             \xmax \space \ymin \space l
             \xmax \space \ymax \space l
             \xxmin\space \ymax \space l
             \xmin \space \ymax \space \xmin \space \yymax\space y
             \xmin \space \yymin\space l
             \xmin \space \ymin \space \xxmin\space \ymin \space y
             h
           \or % 3
             \xmin \space \ymin \space m
             \xmax \space \ymin \space l
             \xmax \space \yymax\space l
             \xmax \space \ymax \space \xxmax\space \ymax \space y
             \xxmin\space \ymax \space l
             \xmin \space \ymax \space \xmin \space \yymax\space y
             \xmin \space \ymin \space l
             h
           \or % 4
             \xmin \space \ymin \space m
             \xxmax\space \ymin \space l
             \xmax \space \ymin \space \xmax \space \yymin\space y
             \xmax \space \yymax\space l
             \xmax \space \ymax \space \xxmax\space \ymax \space y
             \xmin \space \ymax \space l
             \xmin \space \ymin\space l
             h
           \or % 5
             \xmin \space \ymin \space m
             \xmax \space \ymin \space l
             \xmax \space \yymax\space l
             \xmax \space \ymax \space \xxmax\space \ymax \space y
             \xmin \space \ymax \space l
             \xmin \space \ymin \space l
             h
           \or % 6
             \xmin \space \ymin \space m
             \xxmax\space \ymin \space l
             \xmax \space \ymin \space \xmax \space \yymin\space y
             \xmax \space \ymax \space l
             \xmin \space \ymax \space l
             \xmin \space \ymin \space l
             h
           \or
             \xxmin\space \ymin \space m
             \xmax \space \ymin \space l
             \xmax \space \ymax \space l
             \xmin \space \ymax \space l
             \xmin \space \yymin\space l
             \xmin \space \ymin \space \xxmin\space \ymin \space y
             h
           \or
             \xmin \space \ymin \space m
             \xmax \space \ymin \space l
             \xmax \space \ymax \space l
             \xxmin\space \ymax \space l
             \xmin \space \ymax \space \xmin \space \yymax\space y
             \xmin \space \ymin \space l
             h
           \or % 9 top open
             \xmin \space \ymax \space m
             \xmin \space \yymin\space l
             \xmin \space \ymin \space \xxmin\space \ymin \space y
             \xxmax\space \ymin \space l
             \xmax \space \ymin \space \xmax \space \yymin\space y
             \xmax \space \ymax \space l
           \or % 10 right open
             \xmax \space \ymax \space m
             \xxmin\space \ymax \space l
             \xmin \space \ymax \space \xmin \space \yymax\space y
             \xmin \space \yymin\space l
             \xmin \space \ymin \space \xxmin\space \ymin \space y
             \xmax\space  \ymin \space l
           \or % 11 bottom open
             \xmax \space \ymin \space m
             \xmax \space \yymax\space l
             \xmax \space \ymax \space \xxmax \space \ymax\space y
             \xxmin\space \ymax \space l
             \xmin \space \ymax \space \xmin \space \yymax\space y
             \xmin \space \ymin \space l
           \or % 12 left open
             \xmin \space \ymax \space m
             \xxmax\space \ymax \space l
             \xmax \space \ymax \space \xmax \space \yymax\space y
             \xmax \space \yymin\space l
             \xmax \space \ymin \space \xxmax\space \ymin \space y
             \xmin \space \ymin \space l
           \or % 13
             \xmin \space \ymax \space m
             \xxmax\space \ymax \space l
             \xmax \space \ymax \space \xmax \space \yymax\space y
             \xmax\space  \ymin \space l
           \or % 14
             \xmax \space \ymax \space m
             \xmax \space \yymin\space l
             \xmax \space \ymin \space \xxmax\space \ymin \space y
             \xmin \space \ymin \space l
           \or % 15
             \xmax \space \ymin \space m
             \xxmin\space \ymin \space l
             \xmin \space \ymin \space \xmin \space \yymin\space y
             \xmin \space \ymax \space l
           \or % 16
             \xmin \space \ymin \space m
             \xmin \space \yymax\space l
             \xmin \space \ymax \space \xxmin\space \ymax \space y
             \xmax \space \ymax \space l
           \or % 17
             \xxmax\space \ymax \space m
             \xmax \space \ymax \space \xmax \space \yymax\space y
           \or % 18
             \xmax \space \yymin\space m
             \xmax \space \ymin \space \xxmax\space \ymin \space y
           \or % 19
             \xxmin\space \ymin \space m
             \xmin \space \ymin \space \xmin \space \yymin\space y
           \or % 20
             \xmin \space \yymax\space m
             \xmin \space \ymax \space \xxmin\space \ymax \space y
           \or % 21
             \xxmax\space \ymax \space m
             \xmax \space \ymax \space \xmax \space \yymax\space y
             \xmin \space \yymax\space m
             \xmin \space \ymax \space \xxmin\space \ymax \space y
           \or % 22
             \xxmax\space \ymax \space m
             \xmax \space \ymax \space \xmax \space \yymax\space y
             \xmax \space \yymin\space m
             \xmax \space \ymin \space \xxmax\space \ymin \space y
           \or % 23
             \xmax \space \yymin\space m
             \xmax \space \ymin \space \xxmax\space \ymin \space y
             \xxmin\space \ymin \space m
             \xmin \space \ymin \space \xmin \space \yymin\space y
           \or % 24
             \xxmin\space \ymin \space m
             \xmin \space \ymin \space \xmin \space \yymin\space y
             \xmin \space \yymax\space m
             \xmin \space \ymax \space \xxmin\space \ymax \space y
           \or % 25
             \xxmax\space \ymax \space m
             \xmax \space \ymax \space \xmax \space \yymax\space y
             \xmax \space \yymin\space m
             \xmax \space \ymin \space \xxmax\space \ymin \space y
             \xxmin\space \ymin \space m
             \xmin \space \ymin \space \xmin \space \yymin\space y
             \xmin \space \yymax\space m
             \xmin \space \ymax \space \xxmin\space \ymax \space y
           \or % 26
             \xmax \space \yymin\space m
             \xmax \space \ymin \space \xxmax\space \ymin \space y
             \xmin \space \yymax\space m
             \xmin \space \ymax \space \xxmin\space \ymax \space y
           \or % 27
             \xxmax\space \ymax \space m
             \xmax \space \ymax \space \xmax \space \yymax\space y
             \xxmin\space \ymin \space m
             \xmin \space \ymin \space \xmin \space \yymin\space y
           \or % 28
           \fi
           \ifnum\mode>\pluseight\space
                                       S
           \else
             \ifnum\dostroke=\plusone  S \fi
             \ifnum\dofill  =\plusone  f \fi
           \fi
           Q}%
      \fi}%
   \wd\scratchbox#1%
   \ht\scratchbox#2%
   \dp\scratchbox#3%
   \box\scratchbox
   \egroup}

\unexpanded\def\pdfbackendactualtext#1#2% not interfaced
  {\clf_startactualtext{#2}%
   #1%
   \clf_stopactualtext}

\let\pdfactualtext\pdfbackendactualtext

% \starttext
%     text \pdfbackendactualtext{Meier}{Müller} text
% \stoptext

\protect \endinput

% \chapter{FIRST}
%
% \goto{bar}[bar]
%
% HERE \pdfannot width 20pt height 20pt depth 20pt {/Subtype /Link /Dest (bar) /Border [1 1 1] /F 4}\par
% HERE \pdfannot width 20pt height 20pt depth 20pt {/Subtype /Link /Dest (foo) /Border [1 1 1] /F 4}\par
%
% \chapter[bar]{SECOND}
%
% THERE \pdfdest name {foo} \par