stable 2006.04.22 10:41

1 files changed, 104 insertions, 1819 deletions

diff --git a/tex/context/base/core-pos.tex b/tex/context/base/core-pos.tex
index 429aefeec..0324e522c 100644
--- a/tex/context/base/core-pos.tex
+++ b/tex/context/base/core-pos.tex
@@ -11,7 +11,8 @@
 %C therefore copyrighted by \PRAGMA. See mreadme.pdf for
 %C details.
 
-% needs a cleanup, things may change
+% needs a cleanup, things may change; we also need to move the mp
+% related code to meta-pos
 
 % shorter tags, ..:achtergrond:.. etc in pos actions
 
@@ -812,6 +813,107 @@
 
 % \appendtoks \registerparoptions \to \everypar
 
+%D Eperimental code, don't use this yet: (must be sped up anyway)
+
+\def\@@noden{node:n:}
+\def\@@nodeo{node:o:}
+\def\@@nodep{node:p:}
+
+\def\nextnodelocation#1%
+  {\pluscounter{\@@noden#1}}
+
+\def\newnodelocation#1%
+  {\ifundefined{\@@noden#1}%
+     \setcounter{\@@noden#1}\zerocount
+     \letgvalue {\@@nodeo#1}\!!zerocount
+   \fi}
+
+\def\tagnodelocation#1%
+  {\xypos{\@@nodep#1:\countervalue{\@@noden#1}}}
+
+\def\getnodelocationp#1{\MPp{\@@nodep#1:\countervalue{\@@noden#1}}}
+\def\getnodelocationx#1{\MPx{\@@nodep#1:\countervalue{\@@noden#1}}}
+\def\getnodelocationy#1{\MPy{\@@nodep#1:\countervalue{\@@noden#1}}}
+
+\def\numnodelocationp#1#2{\MPp{\@@nodep#1:\number#2}}
+\def\numnodelocationx#1#2{\MPx{\@@nodep#1:\number#2}}
+\def\numnodelocationy#1#2{\MPy{\@@nodep#1:\number#2}}
+
+\def\getnodelocationn#1{\countervalue{\@@noden#1}}
+\def\getnodelocationo#1{\getvalue    {\@@nodeo#1}}
+
+\chardef\nodelocationmode\plusone
+
+\def\analyzenodelocation#1%
+  {\doanalyzenodelocation{#1}{\getnodelocationn{#1}}\zerocount}
+
+\def\doanalyzenodelocation#1#2#3% class n default
+  {\begingroup
+   \donefalse
+   \ifcase\nodelocationmode
+     % do nothing
+   \else
+     \edef\nodelocationselfn{#2}%
+     \edef\nodelocationselfp{\numnodelocationp{#1}\nodelocationselfn}%
+     \edef\nodelocationselfx{\numnodelocationx{#1}\nodelocationselfn}%
+     \edef\nodelocationselfy{\numnodelocationy{#1}\nodelocationselfn}%
+     \scratchcounter\plusone
+     \doloop
+       {\ifnum\recurselevel=\nodelocationselfn\relax
+          \donetrue
+        \else
+          \edef\nodelocationotherp{\numnodelocationp{#1}\recurselevel}%
+          \edef\nodelocationotherx{\numnodelocationx{#1}\recurselevel}%
+          \edef\nodelocationothery{\numnodelocationy{#1}\recurselevel}%
+          \ifcase\nodelocationmode
+          \or
+            % ok for single column
+            \ifcase\nodelocationotherp\relax
+              \exitloop
+            \else\ifnum\nodelocationotherp<\nodelocationselfp\relax
+              \donetrue \advance\scratchcounter\plusone
+            \else\ifnum\nodelocationotherp>\nodelocationselfp\relax
+              % skip
+            \else\ifdim\nodelocationothery>\nodelocationselfy\relax
+              \donetrue \advance\scratchcounter\plusone
+            \else\ifdim\nodelocationothery<\nodelocationselfy\relax
+              % skip
+            \else\ifdim\nodelocationotherx<\nodelocationselfx\relax
+              \donetrue \advance\scratchcounter\plusone
+            \fi\fi\fi\fi\fi\fi
+          \or
+            % acceptable for double column
+            \ifcase\nodelocationotherp\relax
+              \exitloop
+            \else\ifnum\nodelocationotherp<\nodelocationselfp\relax
+              \donetrue \advance\scratchcounter\plusone
+            \else\ifnum\nodelocationotherp>\nodelocationselfp\relax
+              % skip
+            \else\ifnum\recurselevel>\nodelocationselfn\relax
+              \donetrue \exitloop
+            \else
+              \donetrue \advance\scratchcounter\plusone
+            \fi\fi\fi\fi
+        \else
+          \exitloop
+        \fi
+        \fi}%
+   \fi
+   \ifdone \else
+     \scratchcounter#3\relax
+   \fi
+   \setxvalue{\@@nodeo#1}{\the\scratchcounter}%
+   \endgroup}
+
+\unexpanded\def\shownodelocation#1%
+  {\analyzenodelocation{#1}%
+   (#1,%
+    n:\getnodelocationn{#1},%
+    p:\getnodelocationp{#1},%
+    x:\getnodelocationx{#1},%
+    y:\getnodelocationy{#1},%
+    o:\getnodelocationo{#1})}
+
 %D \macros
 %D   {doifoverlappingelse}
 %D
@@ -824,37 +926,6 @@
 %D   {action when not overlapping}
 %D \stoptyping
 
-% \def\doifoverlappingelse#1#2#3#4%
-%   {\relax\ifnum\MPp{#1}=\MPp{#2}\relax
-%      \bgroup
-%      \donefalse
-%      \def\check##1##2%
-%        {\ifdone\else
-%           \ifdim\dimen1##1<\dimen0 \else \ifdim\dimen1##1>\dimen2 \else
-%             \ifdim\dimen1##2<\dimen4 \else \ifdim\dimen1##2>\dimen6 \else
-%               \donetrue
-%             \fi\fi
-%           \fi\fi
-%         \fi}%
-%      \dimen 0=\MPx{#1}%
-%      \dimen 2=\MPx{#1}\advance\dimen 2  \MPw{#1}%
-%      \dimen 4=\MPy{#1}\advance\dimen 4 -\MPd{#1}%
-%      \dimen 6=\MPy{#1}\advance\dimen 6  \MPh{#1}%
-%      \dimen10=\MPx{#2}%
-%      \dimen12=\MPx{#2}\advance\dimen12  \MPw{#2}%
-%      \dimen14=\MPy{#2}\advance\dimen14 -\MPd{#2}%
-%      \dimen16=\MPy{#2}\advance\dimen16  \MPh{#2}%
-%     %\message{\the\dimen 0-\the\dimen 2,\the\dimen 4-\the\dimen 6}\wait
-%     %\message{\the\dimen10-\the\dimen12,\the\dimen14-\the\dimen16}\wait
-%      \check04\check24\check26\check06\ifdone\egroup#3\else\egroup#4\fi
-%    \else
-%      #4%
-%    \fi}
-
-% \newdimen\overlappingmargin \overlappingmargin\zeropoint
-%
-% \overlappingmargin-2sp % better
-
 \def\overlappingmargin{-2\scaledpoint}
 
 \def\doifoverlappingelse#1#2%
@@ -936,1796 +1007,10 @@
    \rawprocesscommalist[#2]\docommando
    \ifdone\egroup#3\else\egroup#4\fi}
 
-\def\doifpositionsonsamepageelse%
+\def\doifpositionsonsamepageelse
   {\dodoifpositionsonsamepageelse{0}}
 
 \def\doifpositionsonthispageelse#1#2#3%
   {\dodoifpositionsonsamepageelse\realfolio}
 
-%D Before we come to graphics support, we have to make sure of
-%D the reference point on the page. The next macro does so and
-%D is hooked into the page building routine.
-
-% in the future, the depth of tail will reflect page depth
-
-\def\textanchor{text:\realfolio}
-
-% \def\placepositionanchors % todo : depth pagebox
-%   {\ifpositioning
-%      \setbox\scratchbox\vbox to \teksthoogte
-%        {\topskipcorrection
-%         \hbox{\strut\dopositionaction\headanchor}%
-%         \vfill
-%         \hbox{\strut\dopositionaction\tailanchor}}%
-%      \dp\scratchbox\zeropoint
-%      \wd\scratchbox\zetbreedte % not \zeropoint, else wrong text backgrounds
-%      \hpos\textanchor{\box\scratchbox}%
-%    \else
-%      \vskip\teksthoogte
-%    \fi}
-
-\def\placepositionanchors % todo : depth pagebox
-  {\ifpositioning
-     \setbox\scratchbox\vbox to \textheight
-       {\simpletopskipcorrection
-        \hbox{\strut\dopositionaction\headanchor}%
-        \vfill
-        \hbox{\strut\dopositionaction\tailanchor}}%
-     \dp\scratchbox\zeropoint
-     \wd\scratchbox\makeupwidth % not \zeropoint, else wrong text backgrounds
-     \hpos\textanchor{\box\scratchbox}%
-   \else
-     \vskip\textheight
-   \fi}
-
-%D The first version of this module implemented head and tail
-%D anchors. Currently we stick to just one anchor and derive
-%D the head and tail anchors from this one.
-
-\def\headanchor{head:\realfolio} % virtual position
-\def\tailanchor{tail:\realfolio} % virtual position
-
-\def\presetpositionanchors% compatibility hack (still needed?)
-  {\ifpositioning
-     \dopresetpositionanchors
-   \fi}
-
-% \def\dopresetpositionanchors
-%   {\bgroup
-%    \dimen0=\ifdim\topskip>\strutht\topskip\else\strutht\fi
-%    \dimen2=\MPy\textanchor
-%    \dimen4=\dimen2
-%    \advance\dimen2 \MPh\textanchor % space is essential
-%    \advance\dimen2 -\dimen0
-%    \advance\dimen4 \strutdp
-%    \dimen6=\MPx\textanchor
-%    \dimen8=\MPw\textanchor
-%    \setxvalue{\POSprefix\headanchor}%
-%      {\realfolio,\withoutpt\the\dimen6,\withoutpt\the\dimen2,%
-%       \withoutpt\the\dimen8,\withoutpt\the\dimen0,\withoutpt\the\strutdp}%
-%    \setxvalue{\POSprefix\tailanchor}%
-%      {\realfolio,\withoutpt\the\dimen6,\withoutpt\the\dimen4,%
-%       \withoutpt\the\dimen8,\withoutpt\the\strutht,\withoutpt\the\strutdp}%
-%   %\showanchor\textanchor\showanchor\headanchor\showanchor\tailanchor\wait
-%    \egroup}
-
-\def\dopresetpositionanchors
-  {\bgroup
-   \!!dimena\ifdim\topskip>\strutht\topskip\else\strutht\fi
-   \!!dimenb\MPy\textanchor
-   \!!dimenc\!!dimenb
-   \advance\!!dimenb \MPh\textanchor % space is essential
-   \advance\!!dimenb -\!!dimena
-   \advance\!!dimenc \strutdp
-   \!!dimend\MPx\textanchor
-   \!!dimene\MPw\textanchor
-   \setxvalue{\POSprefix\headanchor}%
-     {\realfolio,\withoutpt\the\!!dimend,\withoutpt\the\!!dimenb,%
-      \withoutpt\the\!!dimene,\withoutpt\the\!!dimena,\withoutpt\the\strutdp}%
-   \setxvalue{\POSprefix\tailanchor}%
-     {\realfolio,\withoutpt\the\!!dimend,\withoutpt\the\!!dimenc,%
-      \withoutpt\the\!!dimene,\withoutpt\the\strutht,\withoutpt\the\strutdp}%
-  %\showanchor\textanchor\showanchor\headanchor\showanchor\tailanchor\wait
-   \egroup}
-
-\def\showanchor#1%
-  {\expanded{\writestatus{#1}
-     {\MPp{#1}\string|\MPx{#1}\string|\MPy{#1}\string|%
-      \MPw{#1}\string|\MPh{#1}\string|\MPd{#1}}}}
-
-%D We set these anchors before and after each page.
-
-\appendtoks \presetpositionanchors \to \beforeeverypage
-\appendtoks \presetpositionanchors \to \aftereverypage
-
-%D \macros
-%D   {positionoverlay,startpositionoverlay}
-%D
-%D As long as we're dealing with graphics it makes much sense
-%D to use the available overlay mechanism. For this purpose, we
-%D define some dedicated overlay extensions.
-%D
-%D \startbuffer[sample]
-%D \defineoverlay [sample] [\positionoverlay{sample}]
-%D
-%D \startpositionoverlay{sample}
-%D   \setMPpositiongraphic{A-1}{connectcenter}{from=A-1,to=A-2}
-%D \stoppositionoverlay
-%D \stopbuffer
-%D
-%D \typebuffer[sample]
-%D
-%D \startbuffer[graphic]
-%D \startMPpositiongraphic{connectcenter}
-%D   path pa, pb ; pair ca, cb ;
-%D   initialize_box(\MPpos{\MPvar{from}}) ; pa := pxy ; ca := cxy ;
-%D   initialize_box(\MPpos{\MPvar{to}}) ; pb := pxy ; cb := cxy ;
-%D   draw pa withcolor red ;
-%D   draw pb withcolor red ;
-%D   draw ca -- cb withcolor blue ;
-%D   anchor_box(\MPanchor{\MPvar{from}}) ;
-%D \stopMPpositiongraphic
-%D \stopbuffer
-%D
-%D We can best demonstrate this in an example, say:
-%D
-%D \startbuffer[text]
-%D \framed
-%D   [backgroundachtergrond=sample,align=middle,width=7cm]
-%D   {We want to connect \hpos {A-1} {this} word with its
-%D    grammatical cousin \hpos {A-2} {that}.}
-%D \stopbuffer
-%D
-%D \typebuffer[text]
-%D
-%D \startlinecorrection
-%D %\getbuffer[graphic,sample,text]
-%D \stoplinecorrection
-%D
-%D The graphic is defined in the following way, using some
-%D macros defined in an auxiliary \METAPOST\ module that is
-%D preloaded.
-%D
-%D \typebuffer[graphic]
-
-\def\MPanchoridentifier{mpa} % {mp-anchor}
-\def\MPoverlayposprefix{MO::}
-
-% obsolete and wrong anyway
-%
-% \long\def\defineMPpositiongraphic#1%
-%   {\long\setvalue{\MPoverlayposprefix#1}}
-
-%D The rest of the definitions concerning such overlays may
-%D look complicated,
-
-\let\currentpositionoverlay\empty
-
-%D Position actions are automatically executed when a position
-%D is set.
-
-% \def\positionoverlay#1%
-%   {\ifpositioning
-%      \vbox to \overlayheight
-%        {\edef\MPanchor##1{\MPpos{#1::\MPanchoridentifier:\realfolio}}%
-%         \the\everyinsertpositionaction
-%         \copyposition{#1::\MPanchoridentifier}{#1::\MPanchoridentifier:\realfolio}%
-%         \hpos
-%           {#1::\MPanchoridentifier:\realfolio}
-%           {\hbox to \overlaywidth{\dopositionaction{#1::\MPanchoridentifier}\hss}}%
-%         \vfill}%
-%    \fi}
-
-\let\MPanchornumber\realfolio
-
-% \def\positionoverlay#1%
-%   {\ifpositioning
-%      \vbox to \overlayheight
-%        {\edef\MPanchorid{#1::\MPanchoridentifier:\MPanchornumber}%
-%         \edef\MPanchor##1{\MPpos{\MPanchorid}}%
-%         \the\everyinsertpositionaction
-%         \copyposition{#1::\MPanchoridentifier}{#1::\MPanchoridentifier:\MPanchornumber}%
-%         \hpos
-%           {#1::\MPanchoridentifier:\MPanchornumber}
-%           {\hbox to \overlaywidth{\dopositionaction{#1::\MPanchoridentifier}\hss}}%
-%         \vfill}%
-%    \fi}
-
-% \def\positionoverlay#1% the test prevents too many redundant positions
-%   {\ifpositioning     % in (not used) text* position layers
-%      \vbox to \overlayheight
-%        {\doifpositionactionelse{#1::\MPanchoridentifier}%
-%           {\edef\MPanchorid{#1::\MPanchoridentifier:\MPanchornumber}%
-%            \edef\MPanchor##1{\MPpos{\MPanchorid}}%
-%            \the\everyinsertpositionaction
-%            \copyposition{#1::\MPanchoridentifier}{#1::\MPanchoridentifier:\MPanchornumber}%
-%            \hpos
-%              {#1::\MPanchoridentifier:\MPanchornumber}%
-%              {\hbox to \overlaywidth{\dopositionaction{#1::\MPanchoridentifier}\hss}}}%
-%           {\hbox to \overlaywidth{\hss}}%
-%         \vfill}%
-%    \fi}
-
-\def\positionoverlay#1% the test prevents too many redundant positions
-  {\ifpositioning     % in (not used) text* position layers
-     \vbox to \overlayheight
-       {\doifpositionactionelse{#1::\MPanchoridentifier}%
-          {\edef\MPanchorid{#1::\MPanchoridentifier:\MPanchornumber}%
-           \edef\MPanchor##1{\MPpos{\MPanchorid}}%
-           \the\everyinsertpositionaction
-           \copyposition{#1::\MPanchoridentifier}{#1::\MPanchoridentifier:\MPanchornumber}%
-           \hpos
-             {#1::\MPanchoridentifier:\MPanchornumber}%
-            % this is ok
-            %{\hbox to \overlaywidth{\dopositionaction{#1::\MPanchoridentifier}\hss}}}%
-            % but this one prevents cyclic runs due to
-            % rounding errors
-             {\setbox\scratchbox\hbox to \overlaywidth
-                {\dopositionaction{#1::\MPanchoridentifier}\hss}%
-              \ht\scratchbox\overlayheight
-              \dp\scratchbox\zeropoint
-              \box\scratchbox}}%
-          {\hbox to \overlaywidth{\hss}}%
-        \vfill}%
-   \fi}
-
-\def\startpositionoverlay#1%
-  {\iftrialtypesetting % we don't want redundant entries in the list
-     \@EA\gobbleuntil\@EA\stoppositionoverlay
-   \else
-     \def\currentpositionoverlay{#1}%
-   \fi}
-
-\def\stoppositionoverlay
-  {\let\currentpositionoverlay\empty}
-
-\def\resetpositionoverlay#1%
-  {\dosetpositionaction{#1::\MPanchoridentifier::}{}}
-
-%D Here the complication has to do with collecting actions
-%D for later execution. This collection is especially handy
-%D when we want to move actions to a specific layer.
-%D Such series of actions are stored in a macro (the one
-%D with the funny \type {++}) which is cleaned up after each
-%D invocation.
-
-\newtoks\everycleanpositionaction
-\newtoks\everyinsertpositionaction
-
-%\def\cleanuppositionaction#1%
-%  {\doifdefined{\POSactionprefix#1++}
-%     {\the\everycleanpositionaction
-%      \setxvalue{\POSactionprefix#1++}{\getvalue{\POSactionprefix#1++}}}}
-
-%\def\cleanuppositionaction#1%
-%  {\ifundefined{\POSactionprefix#1++}\else
-%     \the\everycleanpositionaction
-%     \setxvalue{\POSactionprefix#1++}{\getvalue{\POSactionprefix#1++}}%
-%   \fi}
-
-\def\cleanuppositionaction#1% not in trialtypesetting
-  {\ifundefined{\POSactionprefix#1++}\else
-     \the\everycleanpositionaction
-     \iflocalpositioning
-       \letgvalue{\POSactionprefix#1++}\empty
-     \else
-       \setxvalue{\POSactionprefix#1++}{\getvalue{\POSactionprefix#1++}}%
-     \fi
-   \fi}
-
-\def\handlepositionaction#1\with#2\on#3%
-  {\bgroup
-   \ifx\currentpositionoverlay\empty
-     \edef\!!stringa{#3}% no layer, just pos itself as anchor
-   \else
-     \edef\!!stringa{\currentpositionoverlay::\MPanchoridentifier}%
-   \fi
-   \edef\!!stringc{\POSactionprefix\!!stringa++}%
-   \expanded{\dosetpositionaction{\!!stringa}{\noexpand\getvalue{\!!stringc}}}%
-   \global\let#1\relax
-   \edef\!!stringb{\executeifdefined\!!stringc\empty}%
-   \setxvalue\!!stringc{\!!stringb#1#2}%
-   \egroup}
-
-%D The indirectness enables us redefine macros for special
-%D purposes, like a cleanup.
-
-\def\handlepositionboxes#1#2#3%
-  {\handlepositionaction\dohandlepositionboxes\with{#1}{#2}{#3}\on{#2}}
-
-\def\doinsertpositionboxes#1#2#3% pos tag setups
-  {\ifnum\MPp{#1}=\realpageno\relax
-     % \doifdefined{\MPoverlayposprefix#1}
-     %   {\getvalue{\MPoverlayposprefix#1}{#1}{#2}{#3}}%
-     \executeifdefined{\MPoverlayposprefix#1}%
-       \gobblethreearguments{#1}{#2}{#3}%
-   \fi}
-
-\appendtoks
-  \let\dohandlepositionboxes\doinsertpositionboxes % was handle ?
-\to \everyinsertpositionaction
-
-\def\docleanpositionboxes#1#2#3% pos tag setups
-  {\ifnum\MPp{#1}<\realpageno \else
-     \noexpand \dohandlepositionboxes{#1}{#2}{#3}% reinsert
-   \fi}
-
-\appendtoks
-  \let\dohandlepositionboxes\docleanpositionboxes
-\to \everycleanpositionaction
-
-%D A position graphic is a normal (non||reused) \METAPOST\
-%D graphic, used immediately, with zero dimensions, so that a
-%D sequence of them does not harm.
-
-\newbox\positiongraphicbox
-
-\def\startMPpositiongraphic % id setups
-  {\dodoublegroupempty\dostartMPpositiongraphic}
-
-\long\def\dostartMPpositiongraphic#1#2#3\stopMPpositiongraphic
-  {\long\setgvalue{MPG:#1}% tag list mpcode
-     {\useMPpositiongraphic{#1}{#2}{#3}}}
-
-%\def\prepareMPpositionvariables
-%  {\doifundefined{\@@meta self}{\setvalue{\@@meta self}{\currentposition}}%
-%   \doifundefined{\@@meta from}{\setvalue{\@@meta from}{\currentposition}}}
-
-\def\prepareMPpositionvariables
-  {\ifundefined{\@@meta self}\setvalue{\@@meta self}{\currentposition}\fi
-   \ifundefined{\@@meta from}\setvalue{\@@meta from}{\currentposition}\fi}
-
-% \long\def\useMPpositiongraphic#1#2#3%
-%   {\bgroup
-%    \prepareMPvariables{#2}%
-%    \prepareMPpositionvariables
-%    \enableincludeMPgraphics
-%    \startMPgraphic#3\stopMPgraphic
-%    \loadMPgraphic{\MPgraphicfile.\the\currentMPgraphic}{}%
-%    \deallocateMPslot\currentMPgraphic
-%    \placeMPgraphic
-%    \egroup}
-
-\newif\ifcollectMPpositiongraphics \collectMPpositiongraphicstrue
-
-\long\def\useMPpositiongraphic#1#2#3%
-  {\bgroup
-   \prepareMPvariables{#2}%
-   \prepareMPpositionvariables
-   \enableincludeMPgraphics
-   \ifcollectMPpositiongraphics
-     \expanded{\startMPdrawing#3\noexpand\stopMPdrawing}%
-     \global\MPdrawingdonetrue
-   \else
-     \startMPgraphic#3\stopMPgraphic
-     \loadMPgraphic{\MPgraphicfile.\the\currentMPgraphic}{}%
-     \deallocateMPslot\currentMPgraphic
-     \placeMPgraphic
-   \fi
-   \egroup}
-
-% Now we need a adapted action handler:
-
-% \def\dopositionaction#1% test saves hash entry in etex
-%   {\ifundefined{\POSactionprefix#1::}\else
-%      \ifnum\MPp{#1}>\zerocount % new
-%        \bgroup
-%        \traceposstring\clap\red{<#1>}%
-%        \the\everyinsertpositionaction
-%        \the\everypositionaction
-%        \ifcollectMPpositiongraphics
-%          % can save a lot of run time
-%          \pushMPdrawing
-%          \MPshiftdrawingtrue
-%          \resetMPdrawing
-%          \getvalue{\POSactionprefix#1::}%
-%          \ifMPdrawingdone
-%            \getMPdrawing
-%          \fi
-%          \resetMPdrawing
-%          \popMPdrawing
-%        \else
-%          \getvalue{\POSactionprefix#1::}%
-%        \fi
-%        \cleanuppositionaction{#1}%
-%        \egroup
-%      \else
-%        % shouldn't happen too often
-%        \traceposstring\clap\cyan{<#1>}%
-%      \fi
-%    \fi}
-
-\def\dopositionaction#1% test saves hash entry in etex
-  {\ifundefined{\POSactionprefix#1::}\else
-     \ifnum\MPp{#1}>\zerocount % new
-       \bgroup
-       \setbox\scratchbox\hbox
-       \bgroup
-       \traceposstring\clap\red{<#1>}%
-       \the\everyinsertpositionaction
-       \the\everypositionaction
-       \ifcollectMPpositiongraphics
-         % can save a lot of run time
-         \pushMPdrawing
-         \MPshiftdrawingtrue
-         \resetMPdrawing
-         \getvalue{\POSactionprefix#1::}%
-         \ifMPdrawingdone
-           \getMPdrawing
-         \fi
-         \resetMPdrawing
-         \popMPdrawing
-       \else
-         \getvalue{\POSactionprefix#1::}%
-       \fi
-       \cleanuppositionaction{#1}%
-       \egroup                % smashed is really needed else
-       \smashedbox\scratchbox % we get problems with too big
-       \egroup                % overlays (s-pre-0x.tex)
-     \else
-       % shouldn't happen too often
-       \traceposstring\clap\cyan{<#1>}%
-     \fi
-   \fi}
-
-\def\MPpositiongraphic
-  {\dodoublegroupempty\doMPpositiongraphic}
-
-% \def\doMPpositiongraphic#1#2% tag setups
-%   {\bgroup
-%    \def\@@meta{#1:}%
-%    \setupMPvariables[#2]%
-%    \prepareMPpositionvariables
-%    \MPshiftdrawingtrue
-%    \def\doMPpositiongraphic##1##2{\getvalue{MPG:##1}}% temp hack
-%    \setbox\positiongraphicbox\hbox
-%      {\ignorespaces
-%       \executeifdefined{MPM:#1}{\executeifdefined{MPG:#1}\donothing}%
-%       \removelastspace}%
-%    \smashbox\positiongraphicbox
-%    \box\positiongraphicbox
-%    \egroup}
-
-\def\doMPpositiongraphic#1#2% tag setups
-  {\bgroup
-   \def\@@meta{#1:}%
-   \setupMPvariables[#2]%
-   \prepareMPpositionvariables
-   \MPshiftdrawingtrue
-   \def\doMPpositiongraphic##1##2%
-     {{% new, see (techniek)
-       \def\@@meta{##1:}%
-       \setupMPvariables[#2,##2]%
-       \prepareMPpositionvariables
-       % and needed
-       \getvalue{MPG:##1}}}% temp hack
-   \setbox\positiongraphicbox\hbox
-     {\ignorespaces
-      \executeifdefined{MPM:#1}{\executeifdefined{MPG:#1}\donothing}%
-      \removelastspace}%
-   \smashbox\positiongraphicbox
-   \box\positiongraphicbox
-   \egroup}
-
-\long\def\startMPpositionmethod#1#2\stopMPpositionmethod
-  {\long\setgvalue{MPM:#1}{#2}} % todo: var list here
-
-%D Simple one position graphics.
-
-\def\setMPpositiongraphic
-  {\dotriplegroupempty\dosetMPpositiongraphic}
-
-\def\dosetMPpositiongraphic#1#2#3% pos tag vars
-  {\ifx\currentpositionoverlay\empty
-     \dosetpositionaction{#1}{\MPpositiongraphic{#2}{#3}}%
-   \else % silly can be one
-     \handlepositiongraphics{#1}{#2}{#3}%
-   \fi}
-
-\def\handlepositiongraphics#1#2#3% combine with boxes
-  {\handlepositionaction\dohandleMPpositiongraphic\with{#1}{#2}{#3}\on{#2}}
-
-\def\doinsertMPpositiongraphic#1#2#3% pos tag setups
-  {\ifnum\MPp{#1}=\realpageno\relax % extra saveguard
-     \def\currentposition{#1}\MPpositiongraphic{#2}{#3}%
-   \fi}
-
-\appendtoks
-  \let\dohandleMPpositiongraphic\doinsertMPpositiongraphic
-\to \everyinsertpositionaction
-
-\def\docleanMPpositiongraphic#1#2#3% pos tag setups
-  {\ifnum\MPp{#1}<\realpageno \else
-     \noexpand \dohandleMPpositiongraphic{#1}{#2}{#3}%
-   \fi}
-
-\appendtoks
-  \let\dohandleMPpositiongraphic\docleanMPpositiongraphic
-\to \everycleanpositionaction
-
-%D Graphics that span two positions.
-
-\def\setMPpositiongraphicrange
-  {\doquadruplegroupempty\dosetMPpositiongraphicrange}
-
-\def\dosetMPpositiongraphicrange#1#2#3#4% bpos epos tag vars
-  {\ifx\currentpositionoverlay\empty
-     \dosetpositionaction{#1}{\MPpositiongraphic{#3}{#4}}%
-   \else
-     \handlepositiongraphicsrange{#1}{#2}{#3}{#4}%
-   \fi}
-
-\def\handlepositiongraphicsrange#1#2#3#4%
-  {\handlepositionaction\dohandleMPpositiongraphicrange\with{#1}{#2}{#3}{#4}\on{#2}}
-
-% \def\doinsertMPpositiongraphicrange#1#2#3#4% pos pos tag setups
-%   {\donefalse
-%         \ifnum\MPp{#1}=\realpageno\relax                          \donetrue
-%    \else\ifnum\MPp{#2}=\realpageno\relax                          \donetrue
-%    \else\ifnum\MPp{#1}<\realpageno\relax\ifnum\MPp{#2}>\realpageno\donetrue
-%    \fi\fi\fi\fi \ifdone
-%      \def\currentposition{#1}\MPpositiongraphic{#3}{#4}%
-%    \fi}
-
-\def\doinsertMPpositiongraphicrange#1#2#3#4% pos pos tag setups
-  {\ifnum\MPp{#1}\MPp{#2}>\zerocount
-     \iflocalpositioning
-       \donetrue
-     \else
-       \donefalse
-       \ifnum\MPp{#1}=\realpageno
-         \donetrue
-       \else\ifnum\MPp{#2}=\realpageno
-         \donetrue
-       \else\ifnum\MPp{#1}<\realpageno\relax\ifnum\MPp{#2}>\realpageno
-         \donetrue
-       \fi\fi\fi\fi
-     \fi
-     \ifdone
-       \def\currentposition{#1}\MPpositiongraphic{#3}{#4}%
-     \fi
-   \fi}
-
-\appendtoks
-  \let\dohandleMPpositiongraphicrange\doinsertMPpositiongraphicrange
-\to \everyinsertpositionaction
-
-\def\docleanMPpositiongraphicrange#1#2#3#4% pos tag setups
-  {\ifnum\MPp{#2}<\realpageno \else
-     \noexpand \dohandleMPpositiongraphicrange{#1}{#2}{#3}{#4}%
-   \fi}
-
-\appendtoks
-  \let\dohandleMPpositiongraphicrange\docleanMPpositiongraphicrange
-\to \everycleanpositionaction
-
-% will be overloaded, and/or code below moved to core-box
-
-\defineoverlay[\v!text-2][\positionoverlay{\v!text-2}]
-\defineoverlay[\v!text-1][\positionoverlay{\v!text-1}]
-\defineoverlay[\v!text+1][\positionoverlay{\v!text+1}]
-\defineoverlay[\v!text+2][\positionoverlay{\v!text+2}]
-
-%D The auxiliary \METAPOST\ macros are defined by default,
-%D by saying:
-
-\appendtoks
-  if unknown context_core : input mp-core.mp ; fi ;
-\to \MPextensions
-
-%D Some of these macros are pretty clever but too complicated
-%D to be nice. When things are kind of stable I'll clean up
-%D this mess.
-
-%D THIS NEEDS A CLEANUP
-
-\setupMPvariables
-  [mpos:box]
-  [linecolor=blue,
-   linewidth=\linewidth,
-   fillcolor=lightgray,
-   filloffset=\!!zeropoint]
-
-\startMPpositiongraphic{mpos:box}{fillcolor,linecolor,linewidth}
-  initialize_box(\MPpos{\MPvar{self}}) ;
-  boxfillcolor  := \MPvar{fillcolor} ;
-  boxlinecolor  := \MPvar{linecolor} ;
-  boxlinewidth  := \MPvar{linewidth} ;
-  boxfilloffset := \MPvar{filloffset} ;
-  draw_box ;
-  anchor_box(\MPanchor{\MPvar{self}}) ;
-\stopMPpositiongraphic
-
-\setupMPvariables
-  [mpos:area]
-  [linecolor=blue,
-   linewidth=\linewidth,
-   fillcolor=lightgray,
-   filloffset=\!!zeropoint]
-
-\startMPpositiongraphic{mpos:area}{fillcolor,linecolor,linewidth}
-  initialize_area(\MPpos{b:\MPvar{self}},\MPpos{e:\MPvar{self}}) ;
-  boxfillcolor  := \MPvar{fillcolor} ;
-  boxlinecolor  := \MPvar{linecolor} ;
-  boxlinewidth  := \MPvar{linewidth} ;
-  boxfilloffset := \MPvar{filloffset} ;
-  draw_area ;
-  anchor_area(\MPanchor{b:\MPvar{self}}) ;
-\stopMPpositiongraphic
-
-%D This is already cleaned up.
-
-% gridtype = 1 => baseline
-% gridtype = 2 => betweenline
-
-\setupMPvariables
-  [mpos:par]
-  [mp=mpos:par:shape,
-   gridtype=0,
-   linetype=1,
-   filltype=1,
-  %snaptops=true, % not that nice: true/false
-   gridcolor=red,
-   linecolor=blue,
-   fillcolor=lightgray,
-   filloffset=\!!zeropoint,
-   linewidth=\linewidth,
-   gridwidth=\linewidth,
-   lineradius=.5\bodyfontsize]
-
-\startuseMPgraphic{mpos:par:shape}
-  \iftracepositions show_par \else draw_par \fi ;
-\stopuseMPgraphic
-
-\startuseMPgraphic{mpos:par:setup}
-   boxgridtype   := \MPvar{gridtype} ;
-   boxlinetype   := \MPvar{linetype} ;
-   boxfilltype   := \MPvar{filltype} ;
-   boxgridcolor  := \MPvar{gridcolor} ;
-   boxlinecolor  := \MPvar{linecolor} ;
-   boxfillcolor  := \MPvar{fillcolor} ;
-   boxfilloffset := \MPvar{filloffset} ;
-   boxlinewidth  := \MPvar{linewidth} ;
-   boxgridwidth  := \MPvar{gridwidth} ;
-   boxlineradius := \MPvar{lineradius} ;
-  %snap_multi_par_tops := \MPvar{snaptops} ;
-\stopuseMPgraphic
-
-\startuseMPgraphic{mpos:par:extra}
-  % user stuff, like:
-  % snap_multi_par_tops := false ;
-\stopuseMPgraphic
-
-% \startMPpositionmethod{mpos:par}
-%   \doifpositionelse{w:\MPvar{self}}
-%     {\startMPpositiongraphic{mpos:par}%
-%          {fillcolor,filloffset,linecolor,gridcolor,linewidth,gridwidth,lineradius}
-%        initialize_area_par(\MPpos{b:\MPvar{self}},
-%                            \MPpos{e:\MPvar{self}},
-%                            \MPpos{w:\MPvar{self}}) ;
-%        \includeMPgraphic{mpos:par:setup} ;
-%        \includeMPgraphic{mpos:par:extra} ;
-%        \includeMPgraphic{\MPvar{mp}} ; % \includeMPgraphic{mpos:par:shape} ;
-%        anchor_par(\MPanchor{b:\MPvar{self}}) ;
-%      \stopMPpositiongraphic}
-%     {\startMPpositiongraphic{mpos:par}%
-%          {fillcolor,filloffset,linecolor,gridcolor,linewidth,gridwidth,lineradius}
-%        initialize_par(\MPpos{b:\MPvar{self}},
-%                       \MPpos{e:\MPvar{self}},
-%                       \MPpos{text:\realfolio},
-%                       \MPpos{p:\MPparcounter},
-%                       \MPvv {p:\MPparcounter}{0,0,0,0,0,0}) ;
-%        \includeMPgraphic{mpos:par:setup} ;
-%        \includeMPgraphic{mpos:par:extra} ;
-%        \includeMPgraphic{\MPvar{mp}} ; % \includeMPgraphic{mpos:par:shape} ;
-%        anchor_par(\MPanchor{b:\MPvar{self}}) ;
-%      \stopMPpositiongraphic}%
-%   \MPpositiongraphic{mpos:par}{}%
-% \stopMPpositionmethod
-
-%D Less readable but shorter.
-
-\ifx\MPparcounter\undefined \newcounter\MPparcounter \fi
-
-\def\MPself     {\MPvar{self}}
-\def\MPbself    {b:\MPself}
-\def\MPeself    {e:\MPself}
-\def\MPwself    {w:\MPself}
-\def\MPparanchor{p:\MPparcounter}
-
-\def\MPl#1{\MPplus{#1}20}
-\def\MPr#1{\MPplus{#1}30}
-
-\startMPpositionmethod{mpos:par} %%%%%%%%%%% will become obsolete
-  \edef\MPparcounter{\MPv\MPbself{1}{0}}%
-  \doifpositionelse\MPwself
-    {\startMPpositiongraphic{mpos:par}%
-         {fillcolor,filloffset,linecolor,gridcolor,linewidth,gridwidth,lineradius}
-       initialize_area_par(\MPpos\MPbself,
-                           \MPpos\MPeself,
-                           \MPpos\MPwself) ;
-       \includeMPgraphic{mpos:par:setup} ;
-       \includeMPgraphic{mpos:par:extra} ;
-       \includeMPgraphic{\MPvar{mp}} ;
-       anchor_par(\MPanchor\MPbself) ;
-     \stopMPpositiongraphic}
-    {\startMPpositiongraphic{mpos:par}%
-         {fillcolor,filloffset,linecolor,gridcolor,linewidth,gridwidth,lineradius}
-       initialize_par(\MPpos\MPbself,
-                      \MPpos\MPeself,
-                      \MPpos\textanchor,
-                      \MPpos\MPparanchor,
-                      \MPvv \MPparanchor{0,0,0,0,0,0}) ;
-       \includeMPgraphic{mpos:par:setup} ;
-       \includeMPgraphic{mpos:par:extra} ;
-       \includeMPgraphic{\MPvar{mp}} ;
-       anchor_par(\MPanchor\MPbself) ;
-     \stopMPpositiongraphic}%
-  \MPpositiongraphic{mpos:par}{}%
-\stopMPpositionmethod
-
-%D The next alternative works in columnsets :
-
-%  \iftracepositions show\else draw\fi_multi_pars ;
-
-\startuseMPgraphic{mpos:par:columnset}
-  \iftracepositions show_multi_pars \else draw_multi_pars \fi ;
-\stopuseMPgraphic
-
-\startMPpositionmethod{mpos:par:columnset}
-  \edef\MPparcounter{\MPv\MPbself{1}{0}}%
-  \startMPpositiongraphic{mpos:par}%
-    {fillcolor,filloffset,linecolor,gridcolor,%
-     linewidth,gridwidth,lineradius}
-    \includeMPgraphic{mpos:par:setup} ;
-    \includeMPgraphic{mpos:par:extra} ;
-    prepare_multi_pars(\MPpos\MPbself,\MPpos\MPeself,\MPpos\MPwself,
-      \MPpos\MPparanchor,\MPvv\MPparanchor{0,0,0,0,0,0}) ;
-    relocate_multipars(-\MPxy\MPanchorid) ; % inside layerpos
-    \includeMPgraphic{\MPvar{mp}} ;
-  \stopMPpositiongraphic
-  \MPpositiongraphic{mpos:par}{}%
-\stopMPpositionmethod
-
-%D \starttyping
-%D \setupbackground
-%D   [test]
-%D   [mp=mpos:par:columnset,
-%D    methodmethode=mpos:par:columnset]
-%D \stoptyping
-
-%D We need to treat floats in a special way.
-
-\appendtoks
-  local_multi_par_area:=\iflocalpositioning true\else false\fi;
-\to \MPinitializations
-
-\def\textbackgroundoverlay#1%
-  {\iflocalpositioning\v!local\else\v!text\fi#1}
-
-\newcounter\localpositionnumber
-
-\def\MPanchornumber
-  {\iflocalpositioning\localpositionnumber\else\realfolio\fi}
-
-%D So far for the trickery.
-
-\newcounter\textbackgrounddepth
-
-\appendtoks
-  \savecurrentvalue\totalnofparbackgrounds\nofparbackgrounds
-\to \everybye
-
-\appendtoks
-  \initializeparbackgrounds
-\to \everystarttext
-
-\ifx\totalnofparbackgrounds\undefined \newcounter\totalnofparbackgrounds \fi
-\ifx\nofparbackgrounds     \undefined \newcounter\nofparbackgrounds      \fi
-
-\def\initializeparbackgrounds
-  {\ifcase\totalnofparbackgrounds\else
-     \global\positioningtrue
-     \global\positioningpartrue
-   \fi}
-
-\unexpanded\def\starttextbackground
-  {\bgroup
-   \increment\textbackgrounddepth
-   \dodoubleempty\dostarttextbackground}
-
-\let\dodostarttextbackground\relax
-\let\dodostoptextbackground \relax
-
-% \def\currentparbackground{background:0}
-% \def\nextparbackground   {background:1}
-
-\def\currentparbackground{pbg:0}
-\def\nextparbackground   {pbg:1}
-
-\def\btbanchor{b:\currentparbackground}
-\def\etbanchor{e:\currentparbackground}
-
-\def\nextbtbanchor{b:\nextparbackground}
-\def\nextetbanchor{e:\nextparbackground}
-
-\def\backgroundvariable#1%
-  {\csname\??td\currenttextbackground#1\endcsname}
-
-% \definetextbackground[more][state=start,backgroundcolor=red] % location=paragraph
-% \definetextbackground[test][state=start,backgroundcolor=green]
-%
-% \page \placefigure[left]{}{}
-%
-% \starttextbackground[test]
-%   \readfile{ward}{}{}
-%   \starttextbackground[more]
-%     \readfile{ward}{}{}
-%   \stoptextbackground
-%   \readfile{ward}{}{}
-% \stoptextbackground
-%
-% \page \placefigure[right]{}{}
-%
-% \starttextbackground[test]
-%   \readfile{ward}{}{}
-%   \starttextbackground[more]
-%     \readfile{ward}{}{}
-%   \stoptextbackground
-%   \readfile{ward}{}{}
-% \stoptextbackground
-
-\def\dostarttextbackground[#1][#2]%
-  {\checktextbackgrounds
-   \def\currenttextbackground{#1}%
-   \doglobal\increment\nofparbackgrounds
-  %\edef\currentparbackground{background:\nofparbackgrounds}%
-   \edef\currentparbackground{pbg:\nofparbackgrounds}%
-   \bgroup
-     \increment\nofparbackgrounds
-    %\xdef\nextparbackground{background:\nofparbackgrounds}%
-     \xdef\nextparbackground{pbg:\nofparbackgrounds}%
-   \egroup
-   % todo : \synchonizepositionpage{b:\currentparbackground}{s:\currentparbackground}%
-   \setuptextbackground[#1][#2]%
-   \let\dodostarttextbackground\relax
-   \let\dodostoptextbackground \relax
-   \doifvalue{\??td#1\c!state}\v!start
-     {\dopresettextbackground{#1}}%
-   \dodostarttextbackground}
-
-% todo \backgroundvariable\c!variant
-
-\def\dopresettextbackground#1% todo: \backgroundparameter
-  {\ExpandFirstAfter\processaction % \EFA niet echt nodig
-     [\getvalue{\??td#1\c!location}]
-     [   \v!text=>\let\dodostarttextbackground\dostarttextbackgroundtxt
-                  \let\dodostoptextbackground \dostoptextbackgroundtxt,
-    \v!paragraph=>\let\dodostarttextbackground\dostarttextbackgroundpar
-                  \let\dodostoptextbackground \dostoptextbackgroundpar,
-         \v!none=>\let\dodostarttextbackground\relax
-                  \let\dodostoptextbackground \relax]%
-   \ifx\dodostarttextbackground\dostarttextbackgroundpar % untested
-     \ifnum\textbackgrounddepth>\plusone % new
-       \let\dodostarttextbackground\dostarttextbackgroundtxt
-       \let\dodostoptextbackground \dostoptextbackgroundtxt
-     \fi
-   \fi
-   \doifelsevalue{\??td#1\c!frame}\v!on
-     {\doifelsevalue{\??td#1\c!corner}\v!round
-        {\setvalue{\??td#1\c!frame}{2}}
-        {\setvalue{\??td#1\c!frame}{1}}}
-     {\setvalue{\??td#1\c!frame}{0}}%
-   \doifelsevalue{\??td#1\c!background}\v!color
-     {\setvalue{\??td#1\c!background}{1}}
-     {\setvalue{\??td#1\c!background}{0}}%
-  %\startpositionoverlay{\v!text\getvalue{\??td#1\c!level}}%
-   \startpositionoverlay{\textbackgroundoverlay{\getvalue{\??td#1\c!level}}}%
-     \expanded
-       {\setMPpositiongraphicrange % moet veel efficienter
-          {\btbanchor}% {b:\currentparbackground}%
-          {\etbanchor}% {e:\currentparbackground}%
-          {\getvalue{\??td#1\c!method}}%
-          {self=\currentparbackground,
-           mp=\getvalue{\??td#1\c!mp},
-           gridtype=\getvalue{\??td#1\c!alternative},
-           filltype=\getvalue{\??td#1\c!background},
-           linetype=\getvalue{\??td#1\c!frame},
-           gridcolor=\getvalue{\??td#1\c!framecolor},
-           linecolor=\getvalue{\??td#1\c!framecolor},
-           fillcolor=\getvalue{\??td#1\c!backgroundcolor},
-           filloffset=\getvalue{\??td#1\c!backgroundoffset},
-           gridwidth=\getvalue{\??td#1\c!rulethickness},
-           linewidth=\getvalue{\??td#1\c!rulethickness},
-           lineradius=\getvalue{\??td#1\c!radius}}}%
-   \stoppositionoverlay}
-
-\def\stoptextbackground
-  {\dodostoptextbackground
-   \carryoverpar\egroup}
-
-\def\starttextbackgroundmanual
-  {\dostartattributes{\??td\currenttextbackground}\c!style\c!color\empty
-   \fpos\currentparbackground\ignorespaces}
-
-\def\stoptextbackgroundmanual
-  {\tpos\currentparbackground
-   \dostopattributes}
-
-\def\dostarttextbackgroundtxt
-  {\ifvmode \leavevmode \fi
-   \dostartattributes{\??td\currenttextbackground}\c!style\c!color\empty
-   \fpos\currentparbackground\ignorespaces}
-
-\def\dostoptextbackgroundtxt
-  {\tpos\currentparbackground
-   \dostopattributes}
-
-% keep this simple one, it's used in prikkels and alike
-%
-% \def\dostarttextbackgroundpar
-%   {\endgraf % new
-%    \getvalue{\??td\currenttextbackground\c!before}%
-%    \noindent\fpos\currentparbackground\ignorespaces
-%    \bgroup
-%    \nobreak \vskip-\lineheight \nobreak
-%    \doassignsomeskip\getvalue{\??td\currenttextbackground\c!topoffset}\to\scratchskip
-%    \kern\scratchskip\nobreak
-%    \dosetleftskipadaption{\getvalue{\??td\currenttextbackground\c!leftoffset}}%
-%    \advance\leftskip\leftskipadaption
-%    \dosetleftskipadaption{\getvalue{\??td\currenttextbackground\c!rightoffset}}%
-%    \advance\rightskip\leftskipadaption
-%    \dostartattributes{\??td\currenttextbackground}\c!style\c!color{}%
-%    \nowhitespace
-%    \seteffectivehsize
-%    \par}
-%
-% \def\dostoptextbackgroundpar
-%   {\par
-%    \dostopattributes
-%    \doassignsomeskip\getvalue{\??td\currenttextbackground\c!bottomoffset}\to\scratchskip
-%    \kern\scratchskip\nobreak
-%    \nobreak \vskip-\lineheight \nobreak
-%    \nowhitespace
-%    \egroup
-%    \nobreak \noindent \strut \hfill \kern\zeropoint \tpos\currentparbackground
-%    \endgraf % new
-%    \getvalue{\??td\currenttextbackground\c!after}}
-
-\def\dostarttextbackgroundpar
-  {\endgraf % new
-   \getvalue{\??td\currenttextbackground\c!before}%
-   \doassignsomeskip\getvalue{\??td\currenttextbackground\c!topoffset}\to\scratchskip
-   \xdef\textbackgroundskip{\the\scratchskip}%
-   \noindent
-   \ifgridsnapping
-     \ifdim\textbackgroundskip>\zeropoint
-       \struttedbox{\hbox{\raise\textbackgroundskip\hbox{\fpos\currentparbackground}}}%
-     \else
-      \fpos\currentparbackground
-     \fi
-   \else
-     \fpos\currentparbackground
-   \fi
-   \bgroup
-   \endgraf % we need a vertical nobreak - 29/06/2004
-   \nobreak \vskip-\lineheight \nobreak
-   \doassignsomeskip\getvalue{\??td\currenttextbackground\c!topoffset}\to\scratchskip
-   \ifgridsnapping \else \ifdim\textbackgroundskip>\zeropoint
-     \kern\textbackgroundskip\nobreak
-   \fi \fi
-   \dosetleftskipadaption{\getvalue{\??td\currenttextbackground\c!leftoffset}}%
-   \advance\leftskip\leftskipadaption
-   \dosetleftskipadaption{\getvalue{\??td\currenttextbackground\c!rightoffset}}%
-   \advance\rightskip\leftskipadaption
-   % new
-   \dosetraggedcommand{\getvalue{\??td\currenttextbackground\c!align}}%
-   \raggedcommand
-   %
-   \dostartattributes{\??td\currenttextbackground}\c!style\c!color\empty
-   \nowhitespace
-   \seteffectivehsize
-   \doinhibitblank %   \blank[\v!disable]% new
-   \par}
-
-\def\dostoptextbackgroundpar
-  {\par
-   \removelastskip % new
-   \dostopattributes
-   \doassignsomeskip\getvalue{\??td\currenttextbackground\c!bottomoffset}\to\scratchskip
-   \ifdim\lastskip>\zeropoint
-     \advance\scratchskip-\lastskip
-   \fi
-   \xdef\textbackgroundskip{\the\scratchskip}%
-   \ifgridsnapping \else \ifdim\textbackgroundskip>\zeropoint
-     \kern\scratchskip\nobreak
-   \fi \fi
-   \nobreak \vskip-\lineheight \nobreak
-   \nowhitespace
-   \egroup
-\bgroup \forgeteverypar % NOT REALLY NEEDED, SAVES HASH/MEM
-   \nobreak \noindent \strut \hfill \kern\zeropoint
-   \ifgridsnapping % experimental, pascal (todo: topoffset in same way)
-     \ifdim\textbackgroundskip>\zeropoint
-       \struttedbox{\hbox{\lower\textbackgroundskip\hbox{\tpos\currentparbackground}}}%
-     \else
-       \tpos\currentparbackground
-     \fi
-   \else
-     \tpos\currentparbackground
-   \fi
-\egroup
-   \endgraf % new
-   \getvalue{\??td\currenttextbackground\c!after}}
-
-\let\textparpages \!!zeropoint
-\let\textparheight\!!zeropoint
-\let\textparwidth \!!zeropoint
-
-\def\calculatetextpardimensions
-  {\docalculatetextpardimensions\btbanchor    \etbanchor    \MPparanchor}
-
-\def\calculatenexttextpardimensions
-  {\docalculatetextpardimensions\nextbtbanchor\nextetbanchor\relax}
-
-\def\docalculatetextpardimensions#1#2#3%
-  {\scratchcounter\MPp#2%\etbanchor
-   \advance\scratchcounter-\MPp#1%\btanchor
-   \edef\textparpages{\the\scratchcounter}%
-   \ifcase\scratchcounter
-     % one page
-     \scratchdimen         \MPy#1%\btanchor
-     \advance\scratchdimen-\MPy#2%\etbanchor
-   \else
-     % two or more pages
-     \scratchdimen         \MPy#1%\btanchor
-     \advance\scratchdimen-\MPy#2%\etbanchor
-     \advance\scratchdimen-\MPy\textanchor
-     \advance\scratchdimen \MPy\textanchor
-     \advance\scratchdimen \MPh\textanchor\relax
-     \ifcase\scratchcounter>2 \ifnum\scratchcounter<5
-       % more pages
-       \scratchdimen\textheight
-       \advance\scratchcounter \minusone
-       \multiply\scratchdimen \scratchcounter
-     \else
-       % keep'm small
-       \scratchdimen5\textheight
-     \fi \fi
-   \fi
-   \edef\textparheight{\the\scratchdimen}%
-   \ifcase\scratchcounter
-     % one page
-     \scratchdimen         \MPx#2%\etbanchor
-     \advance\scratchdimen-\MPx#1%\btanchor
-   \else
-     % two or more pages / maybe also hang
-     \ifx#3\relax
-       \scratchdimen\makeupwidth % \textwidth
-     \else
-       \scratchdimen\MPw\MPparanchor
-       \advance\scratchdimen-\MPl\MPparanchor
-       \advance\scratchdimen-\MPr\MPparanchor
-     \fi
-   \fi
-   \edef\textparwidth{\the\scratchdimen}}
-
-\def\mintextparheight{4\lineheight}
-
-\def\dontsplitnexttextbackground % dangerous but useful
-  {\ifdim\pagetotal>\textheight \else
-     \ifdim\pagegoal=\maxdimen \else
-      \calculatenexttextpardimensions
-      % too tricky
-      % \scratchdimen=\textparheight
-      % \advance\scratchdimen\pagetotal\relax
-      % \ifdim\scratchdimen>\pagegoal
-      % \page
-      % \fi
-      \ifdim\textparheight>\zeropoint
-        \ifdim\textparheight>\mintextparheight\else
-          \page % option
-        \fi
-      \fi
-    \fi
-   \fi}
-
-\def\definetextbackground
-  {\dodoubleempty\dodefinetextbackground}
-
-\def\dodefinetextbackground[#1][#2]%
-  {\ifsecondargument % why ?
-     \copyparameters[\??td#1][\??td]
-       [\c!state,\c!location,\c!alternative,\c!mp,\c!method,
-        \c!background,\c!backgroundcolor,\c!corner,\c!level,
-        \c!backgroundoffset,\c!before,\c!after,\c!align,
-        \c!radius,\c!frame,\c!framecolor,\c!rulethickness,
-        \c!leftoffset,\c!rightoffset,\c!topoffset,\c!bottomoffset]%
-     \getparameters[\??td#1][#2]%
-     \doifvalue{\??td#1\c!state}\v!start\checktextbackgrounds
-     \unexpanded\setvalue{#1}%
-       {\groupedcommand{\starttextbackground[#1]}{\stoptextbackground}}%
-     \setvalue{\e!start#1}{\starttextbackground[#1]}%
-     \setvalue{\e!stop #1}{\stoptextbackground}%
-   \fi}
-
-\def\setuptextbackground
-  {\dodoubleargument\dosetuptextbackground}
-
-\def\dosetuptextbackground[#1][#2]%
-  {\ifsecondargument
-     \doifelsenothing{#1}
-       {\dodosetuptextbackground{#2}\empty}
-       {\processcommalist[#1]{\dodosetuptextbackground{#2}}}%
-   \else
-     \dodosetuptextbackground{#1}\empty
-   \fi}
-
-\def\dodosetuptextbackground#1#2%
-  {\getparameters[\??td#2][#1]%
-   \def\currenttextbackground{#2}%
-   \doifvalue{\??td#2\c!state}\v!start\checktextbackgrounds}
-
-\let\currenttextbackground\empty
-
-\def\checktextbackgrounds
-  {\ifproductionrun
-     \enabletextarearegistration
-     \enablehiddenbackground
-   \fi}
-
-\setuptextbackground
-  [\c!mp=mpos:par:columnset,      % buggy: mpos:par:shape
-   \c!method=mpos:par:columnset, %
-   \c!state=\v!start,
-   \c!location=\v!text,
-   \c!leftoffset=\!!zeropoint, % 1em,
-   \c!rightoffset=\getvalue{\??td\currenttextbackground\c!leftoffset},
-   \c!topoffset=\!!zeropoint,  % \v!medium,
-   \c!bottomoffset=\getvalue{\??td\currenttextbackground\c!topoffset},
-   \c!level=-1,
-   \c!alternative=0,
-   \c!align=,
-   \c!background=\v!color,
-   \c!backgroundcolor=lightgray,
-   \c!backgroundoffset=\!!zeropoint,
-   \c!corner=\v!rectangular,
-   \c!radius=.5\bodyfontsize,
-   \c!frame=\v!on,
-   \c!framecolor=blue,
-   \c!rulethickness=\linewidth]
-
-%D As an example we define a grid background:
-
-\definetextbackground
-  [\v!grid]
-  [\c!state=\v!stop,
-   \c!location=\v!paragraph,
-   \c!frame=\v!off,
-   \c!framecolor=red,
-   \c!background=,
-   \c!alternative=1]
-
-\ifx\basegrid\undefined \else \letvalue\v!grid=\basegrid \fi
-
-% lelijk, aanpassen, opties
-
-\setupMPvariables
-  [mpos:connect]
-  [linecolor=red,
-   linewidth=1pt]
-
-\setupMPvariables
-  [mpos:encircle]
-  [fillcolor=lightgray,
-   filloffset=\!!zeropoint,
-   linecolor=blue,
-   linewidth=1pt]
-
-\startuseMPgraphic{mpos:common:ec}
-  path pa ; pair ca ; color lc ; numeric lw ;
-  lw := \MPvar{linewidth} ;
-  lc := \MPvar{linecolor} ;
-  initialize_box(\MPpos{\MPvar{self}}) ;
-  pa := pxy ; ca := cxy ; pa := boundingbox pa enlarged 2lw ;
-  pa := llcorner pa...lrcorner pa...urcorner pa...ulcorner pa...cycle ;
-  drawoptions (withpen pencircle scaled lw withcolor lc) ;
-\stopuseMPgraphic
-
-\startMPpositiongraphic{mpos:encircle}{linecolor,fillcolor,linewidth}
-  \includeMPgraphic{mpos:common:ec}
-  fill pa withcolor \MPvar{fillcolor} ; draw pa ;
-  anchor_box(\MPanchor{\MPvar{self}}) ;
-\stopMPpositiongraphic
-
-\startMPpositiongraphic{mpos:connect}{linecolor,linewidth}
-  path pb, pc ; pair cb, cc ;
-  \includeMPgraphic{mpos:common:ec}
-  initialize_box(\MPpos{\MPvar{to}}) ;
-  pb := pxy ; cb := cxy ; pb := boundingbox pb enlarged 2lw ;
-  pb := llcorner pb...lrcorner pb...urcorner pb...ulcorner pb...cycle ;
-  pc := ca {up} .. {down} cb ;
-  cc := (pc intersection_point pa) ;
-  if intersection_found :
-    pc := pc cutbefore cc ;
-    cc := (pc intersection_point pb) ;
-    if intersection_found :
-      pc := pc cutafter cc ;
-      drawarrow pc ; drawarrow reverse pc ;
-    fi ;
-  fi ;
-  anchor_box(\MPanchor{\MPvar{self}}) ;
-\stopMPpositiongraphic
-
-%D \macros
-%D   {stackposdown, stackposup, stackposleft,stackposright}
-%D
-%D A non graphic example of the use of positioning, is to stack
-%D text in for instance the margin.
-%D
-%D \stackposdown \inleft {some text}The text \type {some text}
-%D goes into the left margin, and \stackposdown \inleft {some
-%D more}\type {some more} as well. When they overlap, they
-%D will not touch.
-%D
-%D Here we said \type {\stackposdown \inleft{some text}}. Instead
-%D of \stackposleft \inleft {one}stacking \stackposleft \inleft
-%D {two}vertically, one can stack horizontally by \stackposleft
-%D \inleft {three}using \type {\stackposleft}.
-%D
-%D We can go in all four directions, using \type {\stackposdown},
-%D \type {\stackposup}, \type {\stackposleft} and \type
-%D {\stackposright}.
-
-\def\stackposdistance{.5em}
-
-\newcounter\currentautopos
-
-\def\POSstackprefix{stack:}
-
-\def\dostackposbox#1#2%
-  {\dowithnextbox
-     {#2{\let\previousautopos\currentautopos
-         \doglobal\increment\currentautopos
-         \hpos{\POSstackprefix\currentautopos}
-           {\doifoverlappingelse{\POSstackprefix\currentautopos}{\POSstackprefix\previousautopos}
-              {#1}
-              {\flushnextbox}}}}%
-     \hbox}
-
-\def\stackposup   {\dostackposbox{\raise\lineheight\flushnextbox}}
-\def\stackposdown {\dostackposbox{\lower\lineheight\flushnextbox}}
-\def\stackposleft {\dostackposbox{\copy\nextbox\hskip\nextboxwd\hskip\stackposdistance}}
-\def\stackposright{\dostackposbox{\hskip\stackposdistance\hskip\nextboxwd\flushnextbox}}
-
-%D \macros
-%D   {stackeddown}
-%D
-%D However, a better implementation is possible with the
-%D following macro. We now have an extra key \type {stack} for
-%D margin settings. When set to \type {yes}, this macro comes
-%D into action.
-
-% \def\stackeddown
-%   {\dowithnextbox
-%      {\doglobal\increment\currentautopos
-%       \hpos{\POSstackprefix\currentautopos}
-%         {\edef\next
-%            {\nextboxht\the\nextboxht
-%             \nextboxdp\the\nextboxdp
-%             \nextboxwd\the\nextboxwd}%
-%          \let\previousautopos\currentautopos
-%          \scratchdimen\zeropoint
-%          \doloop
-%            {\decrement\previousautopos
-%             \doifoverlappingelse{\POSstackprefix\currentautopos}{\POSstackprefix\previousautopos}
-%               {\advance\scratchdimen\MPh{\POSstackprefix\previousautopos}%
-%                \advance\scratchdimen\MPd{\POSstackprefix\previousautopos}}%
-%               \exitloop
-%             \ifnum\previousautopos<\zerocount\exitloop\fi}%
-%         % \ifdim\scratchdimen>\zeropoint
-%            \setbox\nextbox\iftracepositions\@EA\ruledhbox\else\@EA\hbox\fi
-%              {\lower\scratchdimen\flushnextbox}%
-%            \next
-%         % \fi
-%          \flushnextbox}}}
-
-% Because there can be many stacked items in a line and successive lines, we
-% play dirty and adapt the position and height of the current node so that
-% this becomes visible to a next pass.
-%
-% \startbuffer
-% \inleft {test 1} test 1 \inleft {test 2} test 2 \endgraf
-% \inleft {test 3} test 3
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-%
-% \startbuffer
-% \inleft {test 1} test 1 \inleft {test 2} test 2 \inleft {test 3} test 3 \endgraf
-% \inleft {test 4} test 4
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-%
-% \startbuffer
-% \inleft {test 1} test 1 \endgraf
-% \inleft {test 2} test 2 \endgraf
-% \inleft {test 3} test 3
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-%
-% \startbuffer
-% \inleft {test 1\\test 1} test 1 \inleft {test 2} test 2 \endgraf
-% \inleft {test 3} test 3
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-%
-% \startbuffer
-% \inleft {test 1\\test 1\\test 1\\test 1\\test 1} test 1 \endgraf
-% test 2 \endgraf
-% \inleft {test 3} test 3
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-%
-% \startbuffer
-% \inleft{test 1} test \inleft{test 2} test \inleft{test 3\\test 3} test
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-%
-% \startbuffer
-% \inleft{test 1\\test 1\\test 1} test \inleft{test 2\\test 2} test \inleft{test 3\\test 3\\test 3} test \endgraf
-% \inleft{test 1\\test 1\\test 1} test \inleft{test 2\\test 2} test \inleft{test 3\\test 3\\test 3} test
-% \stopbuffer
-% \getbuffer \typebuffer \flushstatus \page
-
-\newdimen\laststackvmove
-
-\def\stackeddown
-  {\bgroup
-   % this macro assumes a few things and is meant to work for margin notes
-   \dowithnextbox
-     {\doglobal\increment\currentautopos
-      \global\laststackvmove\zeropoint
-      \hpos{\POSstackprefix\currentautopos}
-        {\edef\next
-           {\nextboxht\the\nextboxht
-            \nextboxdp\the\nextboxdp
-            \nextboxwd\the\nextboxwd}%
-         \let\previousautopos\currentautopos
-         \scratchdimen\zeropoint
-         \scratchcounter\zerocount
-         \doloop
-           {\decrement\previousautopos\relax
-            \edef\currentposition {\POSstackprefix\currentautopos}%
-            \edef\previousposition{\POSstackprefix\previousautopos}%
-            \ifnum\MPp\currentposition=\MPp\previousposition\relax
-              %\registerstatus{doing \currentautopos/\previousautopos}%
-              \doifoverlappingelse\currentposition\previousposition
-                {\scratchskip         \MPy\currentposition
-                 \advance\scratchskip-\MPy\previousposition
-                 \advance\scratchskip-\MPd\currentposition  % untested
-                 \advance\scratchskip \MPd\previousposition % untested
-                 \advance\scratchskip \MPh\currentposition
-                 % todo: also take depth into account
-                 \relax
-                 \ifdim\scratchskip<\scratchdimen
-                   %\registerstatus{no \the\scratchskip}%
-                 \else
-                   %\registerstatus{yes \the\scratchskip}%
-                   \scratchdimen\scratchskip
-                 \fi}%
-                \donothing % {\registerstatus{next}}%
-              \ifnum\previousautopos<\zerocount\exitloop\fi
-            \else
-              \exitloop
-            \fi}%
-         \ifdim\scratchdimen=\zeropoint \else
-           \bgroup
-           \edef\currentposition{\POSstackprefix\currentautopos}%
-           \scratchskip\scratchdimen
-           \advance\scratchskip\MPh\currentposition
-           \scratchdimen-\scratchdimen
-           \advance\scratchdimen\MPy\currentposition
-           %\registerstatus{old \currentautopos: \MPy\currentposition/\MPh\currentposition}%
-           \expanded{\replacepospxywhd
-             {\currentposition}{\MPp\currentposition}{\MPx\currentposition}{\the\scratchdimen}%
-             {\MPw\currentposition}{\the\scratchskip}{\MPd\currentposition}}%
-           %\registerstatus{new \currentautopos: \MPy\currentposition/\MPh\currentposition}%
-           \egroup
-           \global\laststackvmove\scratchdimen % new
-           \setbox\nextbox\iftracepositions\@EA\ruledhbox\else\@EA\hbox\fi
-             {\lower\scratchdimen\flushnextbox}%
-           \next
-           %\registerstatus{\strut}%
-         \fi
-         \flushnextbox}%
-        \egroup}}
-
-%D The next hack make sure that margin texts near faulty
-%D strutted lines are handled ok.
-
-\newif\ifrepositionmarginbox % \repositionmarginboxtrue
-
-\newcounter\currentmarginpos
-
-% \def\dopositionmarginbox#1%
-%   {\bgroup
-%    \ifrepositionmarginbox
-%      \doglobal\increment\currentmarginpos
-%      \setposition{\s!margin:\currentmarginpos}%
-%      \scratchdimen=\MPy{\s!margin:\currentmarginpos}%
-%      \doglobal\increment\currentmarginpos
-%      \advance\scratchdimen by -\MPy{\s!margin:\currentmarginpos}%
-%      \advance\scratchdimen by -\strutdp
-%      \setbox#1=\hbox
-%        {\setposition{\s!margin:\currentmarginpos}\raise\scratchdimen\box#1}%
-%      \dp#1=\!!zeropoint
-%      \ht#1=\!!zeropoint
-%    \fi
-%    \vadjust{\box#1}%
-%    \egroup}
-
-\def\dopositionmarginbox#1% how about page boundaries !
-  {\bgroup
-   \ifrepositionmarginbox
-     \doglobal\increment\currentmarginpos
-     \setposition{\s!margin:\currentmarginpos}%
-     \scratchdimen\MPy{\s!margin:\currentmarginpos}%
-     \doglobal\increment\currentmarginpos
-     \advance\scratchdimen -\MPy{\s!margin:\currentmarginpos}%
-     \advance\scratchdimen -\strutdp
-     % new
-     \setbox#1\hbox
-       {\hskip-\MPx{\s!margin:\currentmarginpos}%
-        \hskip\MPx{head:\realfolio}%
-        \box#1}%
-     % so far
-     \setbox#1\hbox
-       {\setposition{\s!margin:\currentmarginpos}%
-        \raise\scratchdimen\box#1}%
-     \dp#1\zeropoint
-     \ht#1\zeropoint
-   \fi
-   \graphicvadjust{\box#1}%
-   \egroup}
-
-%D For a right menu, a sequence of calls to \type
-%D {right_menu_button} is generated.
-%D
-%D \starttyping
-%D right_menu_button (n, p, s=0/1/2, x, y, w, h, d) ;
-%D \stoptyping
-%D
-%D Here, n is the number of the button, s a status variable,
-%D while the rest is positional info. The status variable is
-%D 0, 1 or~2: not found, found and found but current page.
-
-% 0=not found 1=found 2=current page
-
-% geen leeg
-
-\newtoks\MPmenutoks
-
-\def\MPmenubuttons#1{\the\MPmenutoks}
-
-\appendtoks \global\MPmenutoks\emptytoks \to \everyshipout
-
-% 0=notfound  1=found  2=currentpage
-
-\def\do@@amposition#1#2#3%
-  {\doifelsevalue{\??am#1\c!position}\v!yes
-     {\doglobal\increment\currentamposition
-      \doifnumberelse{#2}
-        {\docheckrealreferencepage{#2}%
-         \global\chardef\currentamrealpage\ifrealreferencepage2\else1\fi}
-        {\doifreferencefoundelse{#2}
-           {\global\chardef\currentamrealpage\ifrealreferencepage2\else1\fi}
-           {\global\chardef\currentamrealpage0}}% % not found
-      \expanded
-        {\doglobal\noexpand\appendtoks
-           #1_menu_button(\currentamposition,\the\currentamrealpage,\noexpand\MPpos{#1:\currentamposition}) ;
-         \to \MPmenutoks}%
-      \hpos{#1:\currentamposition}{#3}}
-     {#3}}
-
-\def\do@@ammenuposition#1%
-  {\ifnum\currentamposition>0
-     \dowithnextbox{\hpos{menu:#1:\realfolio}{\flushnextbox}}\hbox
-   \fi}
-
-%D \macros
-%D   {GFC, GTC, GSC}
-%D
-%D The next macros extend tables and tabulation with
-%D backgrounds and position related features. Areas are
-%D specified with symbolic names, and symbolic references to
-%D the graphics involved. Each table has its own namespace.
-
-\newcounter\noftabpositions
-\newtoks   \posXCtoks
-
-\def\tbPOSprefix
-  {tbp:\noftabpositions:}
-
-\def\tablepos
-  {\scratchtoks\posXCtoks
-   \global\posXCtoks\emptytoks
-   \the\scratchtoks}
-
-\let\tabulatepos\tablepos
-
-\def\dodododoGSC[#1:#2]%
-  {\remappositionframed{#2}{\tbPOSprefix#1}%
-   \bpos{\tbPOSprefix#1}%
-   \doglobal\appendtoks\@EA\epos\@EA{\tbPOSprefix#1}\to\posXCtoks}
-
-\def\dododoGSC[#1:#2:#3]%
-  {\doglobal\appendtoks\dodododoGSC[#1:#2]\to\posXCtoks\NC}
-
-\def\dodoGSC[#1]%
-  {\def\docommando##1{\dododoGSC[##1:##1]}%
-   \processcommalist[#1]\docommando}
-
-\def\dodododoGFC[#1:#2:#3]%
-  {\remappositionframed{#2}{\tbPOSprefix#1}%
-   \bpos{\tbPOSprefix#1}}
-
-\def\dododoGFC[#1]%
-  {\def\docommando##1{\dodododoGFC[##1:##1]}%
-   \processcommalist[#1]\docommando}
-
-\def\dodoGFC[#1]%
-  {\doglobal\appendtoks\dododoGFC[#1]\to\posXCtoks\NC}
-
-\def\dododododoGTC[#1:#2]%
-  {\epos{\tbPOSprefix#1}}
-
-\def\dodododoGTC[#1]%
-  {\def\docommando##1{\dododododoGTC[##1:##1]}%
-   \processcommalist[#1]\docommando}
-
-\def\dododoGTC[#1]%
-  {\doglobal\appendtoks\dodododoGTC[#1]\to\posXCtoks}
-
-\def\dodoGTC[#1]%
-  {\doglobal\appendtoks\dododoGTC[#1]\to\posXCtoks\NC}
-
-\def\dodododoXC[#1#2]%
-  {\if#1>\dodoGFC  [#2:#2]\else
-   \if#1+\dodoGFC  [#2:#2]\else
-   \if#1<\dodoGTC  [#2:#2]\else
-   \if#1-\dodoGTC  [#2:#2]\else
-   \if#1=\dodoGSC  [#2:#2]\else
-         \dodoGSC[#1#2:#1#2]\fi\fi\fi\fi\fi}
-
-\def\dododoXC#1%
-  {\dodododoXC[#1]}
-
-\def\dodoXC[#1]%
-  {{\let\NC\relax\processcommalist[#1]\dododoXC}}
-
-\def\doGSC[#1]{\iffirstargument\dodoGSC[#1]\else\expandafter\NC\fi}
-\def\doGFC[#1]{\iffirstargument\dodoGFC[#1]\else\expandafter\NC\fi}
-\def\doGTC[#1]{\iffirstargument\dodoGTC[#1]\else\expandafter\NC\fi}
-\def\doXC [#1]{\iffirstargument\dodoXC [#1]\else\expandafter\fi\NC}
-
-\def\tbGSC{\dosingleempty\doGSC}
-\def\tbGFC{\dosingleempty\doGFC}
-\def\tbGTC{\dosingleempty\doGTC}
-\def\tbXC {\dosingleempty\doXC }
-
-%D The amount of code to support tables and tabulation is
-%D rather minimalistic.
-
-\let\tabulatepos\tablepos
-
-\def\tabulatenormalpos
-  {\hss\tabulatepos\hss}
-
-\def\tabulateequalpos
-  {\setbox\scratchbox\hbox{\tabulateEQ}%
-   \hbox to \wd\scratchbox{\hss\kern\zeropoint\tabulatepos\hss}%
-   \hskip-\wd\scratchbox
-   \box\scratchbox}
-
-\def\tabulatenormalcolumn#1% overloaded
-  {&\iftabulateequal\tabulateequalpos\else\tabulatenormalpos\fi
-   &\global\chardef\tabulatetype#1&}
-
-\def\tabulateequalcolumn#1% overloaded
-  {&\tabulateequalpos
-   &\global\chardef\tabulatetype#1&}
-
-\appendtoks
-  \doglobal\increment\noftabpositions
-\to \everytabulate
-
-%D In order to prevent potential clashes with abbreviations,
-%D postpone the mapping.
-
-\appendtoks
-  \let\GSC\tbGSC \let\GFC\tbGFC \let\GTC\tbGTC \let\XC\tbXC
-\to \everytabulate
-
-%D \macros
-%D   {definepositionframed}
-%D
-%D The next example show how to provide backgrounds to table
-%D cells. First we define some framed backgrounds.
-%D
-%D \startbuffer
-%D \definepositionframed[x][background=color,backgroundcolor=red]
-%D \definepositionframed[y][background=color,backgroundcolor=green]
-%D \definepositionframed[z][background=color,backgroundcolor=blue]
-%D \stopbuffer
-%D
-%D \typebuffer
-%D
-%D % \getbuffer
-%D
-%D \startbuffer
-%D \starttabulate[|c|c|c|]
-%D \GFC[f:x] this is a small  \NC       table            \NC     in which we \NC \FR
-%D \NC       will demonstrate \GFC[g:z] that this        \GTC[g] positioning \NC \MR
-%D \GSC[e:y] mechanism also   \GTC[f]   works quite well \NC     in tables   \NC \LR
-%D \stoptabulate
-%D \stopbuffer
-%D
-%D The table itself defines three areas (a, b and~c) using
-%D these frames.
-%D
-%D \typebuffer
-%D % \getbuffer
-%D
-%D Tables (based on \TABLE) are supported by:
-
-\def\normalTABLEsimplebar {\unskip\!ttRightGlue&\tablepos&}                       % |
-\def\normalTABLEcomplexbar{\unskip\!ttRightGlue&\omit\tablepos\!ttAlternateVrule} % \|
-\def\normalTABLEquote     {\unskip\!ttRightGlue&\omit\tablepos&}                  % "
-
-\appendtoks
-  \doglobal\increment\noftabpositions
-\to \everytable
-
-%D Since we don't want nameclashes:
-
-\appendtoks
-  \let\GSC\tbGSC \let\GFC\tbGFC \let\GTC\tbGTC \let\XC\tbXC
-\to \everytable
-
-%D In the previous example, we could have provided an overlay to
-%D the framed definition. A more direct approach is demonstrated
-%D below:
-%D
-%D \startbuffer
-%D \def\cw#1{\color[white]{#1}}
-%D
-%D \startMPpositiongraphic{tableshade}
-%D   initialize_area(\MPpos{\MPvar{from}},\MPpos{\MPvar{to}}) ;
-%D   color c ; c := \MPvar{color} ;
-%D   linear_shade(pxy,0,.4c,.9c) ;
-%D   anchor_area(\MPanchor{\MPvar{from}}) ;
-%D \stopMPpositiongraphic
-%D
-%D \setMPpositiongraphic{b:x}{tableshade}{from=b:x,to=e:x,color=red}
-%D \setMPpositiongraphic{b:y}{tableshade}{from=b:y,to=e:y,color=green}
-%D \setMPpositiongraphic{b:z}{tableshade}{from=b:z,to=e:z,color=blue}
-%D \stopbuffer
-%D
-%D \typebuffer \getbuffer
-%D
-%D The definition of the table looks about the same as the
-%D previous one:
-%D
-%D \startbuffer
-%D \starttable[|c|c|c|]
-%D \GFC[b:z] \cw{this is a small}  \NC       \cw{table}            \NC     in which we      \NC \FR
-%D \NC       \cw{will demonstrate} \GFC[c:y] \cw{that this}        \GTC[c] \cw{positioning} \NC \MR
-%D \GSC[a:x] \cw{mechanism also}   \GTC[b]   \cw{works quite well} \NC     in tables        \NC \LR
-%D \stoptable
-%D \stopbuffer
-%D
-%D \typebuffer
-%D
-%D \getbuffer
-
-% \definepositionframed[w][background=color,backgroundcolor=yellow]
-% \definepositionframed[x][background=color,backgroundcolor=red]
-% \definepositionframed[y][background=color,backgroundcolor=green]
-% \definepositionframed[z][background=color,backgroundcolor=blue]
-%
-% \starttabulate[|c|c|c|]
-% \NC this is a small  \NC table            \NC in which we \NC \FR
-% \NC will demonstrate \NC that this        \NC positioning \NC \MR
-% \NC mechanism also   \NC works quite well \NC in tables   \NC \LR
-% \stoptabulate
-%
-% \starttabulate[|c|c|c|]
-% \GFC[f:x] this is a small      \GTC      table            \NC     in which we \NC \FR
-% \NC       will demonstrate     \GFC[g:z] that this        \GTC[g] positioning \NC \MR
-% \GSC[e:y] mechanism also       \GTC[f]   works quite well \NC     in tables   \NC \LR
-% \stoptabulate
-%
-% \starttabulate[|c|c|c|]
-% \GFC[f:x,d:w] this is a small  \GTC[d]   table            \NC     in which we \NC \FR
-% \NC           will demonstrate \GFC[g:z] that this        \GTC[g] positioning \NC \MR
-% \GSC[e:y]     mechanism also   \GTC[f]   works quite well \NC     in tables   \NC \LR
-% \stoptabulate
-%
-% \starttabulate[|c|c|c|]
-% \XC[+f:x] this is a small  \XC      table            \NC     in which we \NC \FR
-% \NC      will demonstrate  \XC[+g:z] that this       \XC[-g] positioning \NC \MR
-% \XC[=e:y] mechanism also   \XC[-f]  works quite well \NC     in tables   \NC \LR
-% \stoptabulate
-%
-% \starttabulate[|c|c|c|]
-% \XC[+f:x,+d:w] this is a small  \XC[-d]   table            \NC     in which we \NC \FR
-% \NC            will demonstrate \XC[+g:z] that this        \XC[-g] positioning \NC \MR
-% \XC[=e:y]       mechanism also  \XC[-f]   works quite well \NC     in tables   \NC \LR
-% \stoptabulate
-
-% evt                  [b:x]
-%
-% \definepositionframed[x][background=color,fillcolor=red]
-% \definepositionframed[y][background=color,fillcolor=green]
-% \definepositionframed[z][background=color,fillcolor=blue]
-
-\def\remappositionframed#1#2% from to
-  {\copyposition{b:#1}{b:#2}%
-   \copyposition{e:#1}{e:#2}%
-   \dosetpositionaction{b:#2}{\dopositionaction{b:#1}}}
-
-\def\definepositionframed
-  {\dodoubleargument\dodefinepositionframed}
-
-\def\dodefinepositionframed[#1][#2]%
-  {\dosetpositionaction{b:#1}{\dopositionframed[#1][#2]}}
-
-\def\positionframed
-  {\dodoubleempty\dopositionframed}
-
-\def\dopositionframed[#1][#2]%
-  {\bgroup
-   \setbox\scratchbox\hbox
-     {\dimen0=\MPx{e:#1}%
-      \advance\dimen0 -\MPx{b:#1}%
-      \dimen2=\MPy{b:#1}%
-      \advance\dimen2 -\MPy{e:#1}%
-      \advance\dimen2 \MPd{e:#1}%
-      \lower\dimen2\hbox
-        {\advance\dimen2 \MPh{b:#1}%
-         \framed
-           [\c!width=\dimen0,\c!height=\dimen2,
-            \c!offset=\v!overlay,#2]{}}}%
-   \smashedbox\scratchbox
-   \egroup}
-
-% \def\sethdistances#1%
-%   {\hbox{\lpos{ml:#1}\hpos{mh:#1}{\strut}\rpos{mr:#1}}}
-%
-% \def\gethdistances#1%
-%   {\scratchdimen\MPx{mh:#1}%
-%    \advance\scratchdimen -\MPx{ml#1}%
-%    \edef\lefthdistance{\the\scratchdimen}%
-%    \scratchdimen\MPx{mr:#1}%
-%    \advance\scratchdimen -\MPx{mh:#1}%
-%    \edef\righthdistance{\the\scratchdimen}}
-
 \protect \endinput
-
-% todo 1: shift down option
-
-\startuseMPgraphic{mpos:par:columnset}
-  \iftracepositions show_multi_pars \else draw_multi_pars \fi ;
-  path p ; p := boundingbox currentpicture ;
-  currentpicture := currentpicture shifted (0,-StrutDepth/2) ;
-  setbounds currentpicture to p ;
-\stopuseMPgraphic
-
-\setupcolors[state=start]
-
-\definetextbackground[underline][location=text,alternative=1,background=,frame=off,distance=2pt]
-
-\definestartstop
-  [underline]
-  [before={\starttextbackground[underline]},
-   after=\stoptextbackground]