path: root/tex/context/base/meta-ini.tex

%D \module
%D   [       file=meta-ini,
%D        version=1999.07.10,
%D          title=\METAPOST\ Graphics, 
%D       subtitle=Initialization, 
%D         author=Hans Hagen,
%D           date=\currentdate,
%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]
%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}{MetaPost Graphics / Initializations}

\unprotect 

\startmessages  dutch  library: metapost
  title: metapost
      1: metapost bibliotheek -- wordt geladen
\stopmessages

\startmessages  english  library: metapost
  title: metapost
      1: loading metapost library --
\stopmessages

\startmessages  german  library: metapost
  title: metapost
      1: loading metapost library --
\stopmessages

\startmessages  czech  library: metapost
  title: metapost
      1: loading metapost library --
\stopmessages

\startmessages  italian  library: metapost
  title: metapost
      1: caricamento della libreria metapost --
\stopmessages

\startmessages  norwegian  library: metapost
  title: metapost
      1: metapost bibliotek -- blir lest inn
\stopmessages

\startmessages  romanian  library: metapost
  title: metapost
      1: se incarca biblioteca metapost --
\stopmessages

%D This module extends the functionality of the support module
%D \type {supp-mps}, the module that is responsible for
%D \METAPOST\ inclusion in \CONTEXT. Some basic macros will be
%D extended. Since some support is depends on \METAPOST\
%D macros. so let's first preload a few auxiliary \METAPOST\
%D files. 

\appendtoks 
  if unknown context_tool : input mp-tool ; fi ;  
  if unknown context_spec : input mp-spec ; fi ;  
  if unknown context_grph : input mp-grph ; fi ;  
\to \MPinitializations 

%D Since we want lables to follow the document settings, we 
%D also set the font related variables.

\appendtoks
  defaultfont  := "\truefontname{Regular}" ;
  defaultscale := \the\bodyfontsize/10pt ; % not good yet
\to \MPinitializations

%D In order to support fancy text features (like outline 
%D fonts), we set: 

\appendtoks
  graphictextformat := "context" ; 
  graphictextdirective "\the\everyMPTEXgraphic" ; 
\to \MPinitializations

%D Some safeguards: 

\appendtoks \let\handlecompoundcharacter\string \to \everyMPgraphic

%D We save the number of graphics for the sake of \TEXEXEC.

\newcounter\totalnumberofMPgraphics 
\def\thecurrentMPgraphic{\the\currentMPgraphic}

\appendtoks 
  \savecurrentvalue\totalnumberofMPgraphics\thecurrentMPgraphic
\to \everybye

%D \macros
%D   {setupMPvariables}
%D
%D When we build collections of \METAPOST\ graphics, like
%D background and buttons, the need for passing settings
%D arises. By (mis|)|using the local prefix that belongs to
%D \type {\framed}, we get a rather natural interface to
%D backgrounds. To prevent conflicts, we will use the \type
%D {-} in \METAPOST\ specific variables, like:
%D
%D \starttypen
%D \setupMPvariables[meta:button][size=20pt]
%D \stoptypen

\def\@@meta{meta:}

\def\setupMPvariables%
  {\dodoubleempty\dosetupMPvariables}

\def\dosetupMPvariables[#1][#2]%
  {\ifsecondargument
     \getrawparameters[#1:][#2]%
   \else
     \getrawparameters[\@@meta][#1]%
   \fi}

\let\@@framed\s!unknown

\def\MPvariable#1%
  {\getvalue{\ifundefined{\@@framed\@@meta#1}\else\@@framed\fi\@@meta#1}}

\let\MPvar\MPvariable

%D \macros 
%D   {startuniqueMPgraphic, uniqueMPgraphic}
%D
%D This macros is probably of most use to myself, since I like
%D to use graphics that adapt themselves. The next \METAPOST\
%D kind of graphic is both unique and reused when possible. 
%D 
%D \starttypen 
%D \defineoverlay[example][\uniqueMPgraphic{test}]
%D
%D \startuniqueMPgraphic {test}
%D   draw unitsquare xscaled \overlaywidth yscaled \overlayheight ; 
%D \stopuniqueMPgraphic 
%D \stoptypen

%D For educational purposes, we show the original version 
%D first. This one used a rather simple method for determining 
%D the uniqueness. 
%D
%D \starttypen 
%D \long\def\startuniqueMPgraphic#1#2\stopuniqueMPgraphic%
%D   {\setvalue{MP:#1}%
%D      {\startreusableMPgraphic{\overlaystamp:#1}#2\stopreusableMPgraphic
%D       \reuseMPgraphic{\overlaystamp:#1}}}
%D 
%D \def\uniqueMPgraphic#1%
%D   {\getvalue{MP:#1}}
%D \stoptypen 
 
\def\overlaystamp% watch the \MPcolor, since colors can be redefined
  {\overlaywidth:\overlayheight:\overlaydepth
  :\MPcolor{\overlaycolor}:\MPcolor{\overlaylinecolor}}
 
%D A better approach is to let additional variables play a role
%D in determining the uniqueness. In the next macro, the
%D second, optional, argument is used to guarantee the
%D uniqueness, as well as prepare variables for passing them to
%D \METAPOST. 
%D 
%D \starttypen
%D \startuniqueMPgraphic{meta:hash}{gap,angle,...}
%D \stoptypen
%D
%D The calling macro also accepts a second argument. For
%D convenient use in overlay definitions, we use \type {{}}
%D instead of \type {[]}.
%D
%D \starttypen
%D \uniqueMPgraphic{meta:hash}{gap=10pt,angle=30}
%D \stoptypen

\def\handleuniqueMPgraphic#1#2#3%
  {\def\@@meta{#1:}%
   \extendMPoverlaystamp{#2}% incl prepare
  %\startreusableMPgraphic{\overlaystamp:#1}#3\stopreusableMPgraphic
  %\getvalue{MP:\overlaystamp:#1}} % no \reuseMPgraphic, else wrong \@@meta
   \ifundefined{MP:\overlaystamp:#1}%
     \enableincludeMPgraphics
     \startMPgraphic#3\stopMPgraphic
     \doifobjectssupportedelse{}{\useMPboxfalse}%
     \ifuseMPbox
       \douseMPbox{MP:\overlaystamp:#1}%
     \else
       \nouseMPbox{MP:\overlaystamp:#1}%
     \fi
   \fi
   \getvalue{MP:\overlaystamp:#1}}

\long\def\startuniqueMPgraphic%
  {\dodoublegroupempty\dostartuniqueMPgraphic}

\long\def\dostartuniqueMPgraphic#1#2#3\stopuniqueMPgraphic%
  {\setvalue{MP:#1}{\handleuniqueMPgraphic{#1}{#2}{#3}}}

\unexpanded\def\uniqueMPgraphic%
  {\dodoublegroupempty\douniqueMPgraphic}

\def\douniqueMPgraphic#1#2%
%  {{\def\@@meta{#1:}\setupMPvariables[#2]\getvalue{MP:#1}{}}}
  {{\setupMPvariables[#1][#2]\getvalue{MP:#1}{}}}

\long\def\handleuseMPgraphic#1#2#3%
  {\bgroup
   \def\@@meta{#1:}%
   \prepareMPvariables{#2}%
   \enableincludeMPgraphics
   \startMPgraphic#3\stopMPgraphic
   \loadMPgraphic{\MPgraphicfile.\the\currentMPgraphic}{}%
   \deallocateMPslot\currentMPgraphic
   \placeMPgraphic
   \egroup}

\long\def\startuseMPgraphic% 
  {\dodoublegroupempty\dostartuseMPgraphic}

\long\def\dostartuseMPgraphic#1#2#3\stopuseMPgraphic% 
  {\long\setgvalue{MP:#1}{\handleuseMPgraphic{#1}{#2}{#3}}}

\long\def\startusableMPgraphic% % redundant but handy 
  {\dodoublegroupempty\dostartusableMPgraphic}

\long\def\dostartusableMPgraphic#1#2#3\stopusableMPgraphic% 
  {\long\setgvalue{MP:#1}{\handleuseMPgraphic{#1}{#2}{#3}}}

\long\def\handlereusableMPgraphic#1#2#3%
  {\bgroup
   \def\@@meta{#1:}%
   \prepareMPvariables{#2}%
   \enableincludeMPgraphics
   \startMPgraphic#3\stopMPgraphic
   \doifobjectssupportedelse{}{\useMPboxfalse}%
   \ifuseMPbox
     \douseMPbox{MP:#1}%
   \else
     \nouseMPbox{MP:#1}%
   \fi
   \getvalue{MP:#1}%
   \egroup}

\long\def\startreusableMPgraphic%
  {\dodoublegroupempty\dostartreusableMPgraphic}

\long\def\dostartreusableMPgraphic#1#2#3\stopreusableMPgraphic%
  {\ifundefined{MP:#1}%
     \long\setgvalue{MP:#1}{\handlereusableMPgraphic{#1}{#2}{#3}}%
   \fi}

\unexpanded\def\useMPgraphic%
  {\dodoublegroupempty\douseMPgraphic}

\def\douseMPgraphic#1#2%
  {{\setupMPvariables[#1][#2]\getvalue{MP:#1}{}}}

\let\reuseMPgraphic\useMPgraphic

\def\enableincludeMPgraphics%
  {\let\handleuseMPgraphic     \thirdofthreearguments
   \let\handlereusableMPgraphic\thirdofthreearguments}

%D One way of defining a stamp is: 
%D 
%D \starttypen 
%D \def\extendMPoverlaystamp#1%
%D   {\def\docommando##1%
%D      {\edef\overlaystamp{\overlaystamp:\MPvariable{##1}}}%
%D    \processcommalist[#1]\docommando}
%D \stoptypen 

%D Since we need to feed \METAPOST\ with expanded dimensions,
%D we introduce a dedicated expansion engine.

\def\prepareMPvariable#1%
  {\ifundefined{\@@framed\@@meta#1}%
     \doprepareMPvariable{\@@meta#1}%
   \else
     \doprepareMPvariable{\@@framed\@@meta#1}%
   \fi}

\def\doprepareMPvariable#1%
  {\doifelsenothing{\getvalue{#1}}
     {\setevalue{#1}{\MPcolor{black}}}
     {\edef\!!stringa{\getvalue{#1}}%
      \convertcommand\!!stringa\to\ascii % otherwise problems 
      \doifcolorelse{\ascii}             % with 2\bodyfontsize
        {\setevalue{#1}{\MPcolor{\getvalue{#1}}}}
        {\setbox\scratchbox=\hbox{\scratchdimen=\getvalue{#1}sp}%
         \ifdim\wd\scratchbox=\zeropoint
           \scratchcounter=\getvalue{#1}\relax
           \setevalue{#1}{\the\scratchcounter}%
         \else
           \scratchdimen=\getvalue{#1}\relax
           \setevalue{#1}{\the\scratchdimen}%
         \fi}}}

%D We redefine \type {\extendMPoverlaystamp} to preprocess
%D variables using \type {\prepareMPvariable}.

\def\extendMPoverlaystamp#1%
  {\def\docommando##1%
     {\prepareMPvariable{##1}%
      \edef\overlaystamp{\overlaystamp:\MPvariable{##1}}}%
   \processcommalist[#1]\docommando}

\def\prepareMPvariables#1%
  {\processcommalist[#1]\prepareMPvariable}

%D \macros
%D   {MPdatafile}
%D
%D We redefine a macro from \type {supp-mps.tex}: 

\def\MPdatafile%
  {\bufferprefix mpd-\the\currentMPgraphic.mpd}

%D We also have to make sure that \METAPOST\ knows this: 

\appendtoks 
  if not known _data_prefix_ :
    string _data_prefix_ , _data_suffix_ ; 
  fi ;
  _data_prefix_ := "\bufferprefix mpd-" ; 
  _data_suffix_ := ".mpd" ; 
\to \MPinitializations 

%D \macros
%D   {getMPdata}
%D
%D The current data is loaded with: 

\def\getMPdata%
  {\startreadingfile
   \readlocfile{\MPdatafile}{}{}%
   \stopreadingfile}

%D When we collect graphics in one file, we run into 
%D troubles, since \METAPOST\ has a built in limit (of 4) 
%D on the number of files it can handle. It's therefore 
%D better to collect all data in one file and filter it. 

\def\getMPdata%
  {\long\def\MPdata##1##2%
     {\ifnum##1=\currentMPgraphic\relax##2\fi}%
   \startreadingfile
   \readlocfile{\MPgraphicfile.mpd}{}{}%
   \stopreadingfile}

%D We have to enable this mechanism with: 

\appendtoks 
  boolean collapse_data ; collapse_data := true ;
  _data_suffix_ := ".mpd" ; % overloads previous one 
\to \MPinitializations 

%D For the moment, the next one is a private macro: 

\def\processMPbuffer%
  {\dosingleempty\doprocessMPbuffer}

\def\doprocessMPbuffer[#1]%
  {\doifelsenothing{#1}
     {\doprocessMPbuffer[\jobname]}
     {\bgroup
      \let\par\empty
      \!!toksa=\emptytoks
      \def\copyMPbufferline{\expandafter\appendtoks\fileline\to\!!toksa}%
      \def\dodoprocessMPbuffer##1%
        {\doprocessfile\scratchread{\TEXbufferfile{##1}}\copyMPbufferline}%
      \processcommalist[#1]\dodoprocessMPbuffer
      \ifMPrun
        \@EA\startMPrun\the\!!toksa\stopMPrun
      \else
        \@EA\startuseMPgraphic\@EA{\@EA\s!dummy\@EA}\the\!!toksa\stopuseMPgraphic
        \useMPgraphic{\s!dummy}%
      \fi
      \egroup}}

%D \macros 
%D   {startMPenvironment, resetMPenvironment}
%D
%D In order to synchronize the main \TEX\ run and the runs 
%D local to \METAPOST, environments can be passed. 

\ifx\everyMPTEXgraphic\undefined
  \newtoks\everyMPTEXgraphic
\fi 

\def\startMPenvironment%                % second arg gobbles spaces, so
  {\dodoubleempty\dostartMPenvironment} % that reset gives \emptytoks

\long\def\dostartMPenvironment[#1][#2]#3\stopMPenvironment%
  {\doif{#1}{\s!reset}{\resetMPenvironment}% % reset mp toks
   \doif{#1}{\v!globaal}{#3}%                % use in main doc too
   \doif{#1}{+}{#3}%                         % use in main doc too
   \convertargument#3\to\ascii
   \expandafter\appendtoks\ascii\to\everyMPTEXgraphic}

\def\resetMPenvironment%
  {\everyMPTEXgraphic=\emptytoks % = is really needed ! 
   \startMPenvironment
     \global\loadfontdefinitionfileoncetrue
   \stopMPenvironment} 

\startMPenvironment
  \global\loadfontdefinitionfileoncetrue
\stopMPenvironment

%D This command takes \type {[reset]} as optional 
%D argument. 
%D
%D \starttypen 
%D \startMPenvironment
%D   \setupbodyfont[pos,14.4pt]
%D \stopMPenvironment
%D
%D \startMPcode
%D   draw btex \sl Hans Hagen etex scaled 5 ; 
%D \stopMPcode
%D \stoptypen 
%D
%D The \type {\resetMPenvironment} is a quick way to erase 
%D the token list. 

%D We don't want spurious files, do we? 

\def\initializeMPgraphics% \unlinkfile{\MPgraphicfile.mp} -> empty file 
  {%\ifx\bufferprefix\empty \else 
     \immediate\openout\MPwrite\MPgraphicfile.mp
     \immediate\write\MPwrite{end.}%
     \immediate\closeout\MPwrite 
   }%\fi}
 
%D Loading specific \METAPOST\ related definitions is 
%D accomplished by: 

\def\douseMPlibrary#1%
  {\doifundefined{\c!file\f!javascriptprefix#1}
     {\setvalue{\c!file\f!javascriptprefix#1}{}
      \makeshortfilename[\f!metapostprefix#1]
      \showmessage{\m!metapost}{1}{#1}
      \startreadingfile
      \readsysfile{\shortfilename}{}{}
      \stopreadingfile}}

\def\useMPlibrary[#1]%
  {\processcommalist[#1]\douseMPlibrary}

%D \macros
%D   {setMPtext, MPtext, MPstring, MPbetex}
%D
%D To be documented: 
%D
%D \starttyping
%D \setMPtext{identifier}{text}
%D
%D \MPtext  {identifier}
%D \MPstring{identifier}
%D \MPbetex {identifier}
%D \stoptyping 

\def\@@MPT{@MPT@}

\def\forceMPTEXgraphic%
  {\long\def\checkMPTEXgraphic##1{\global\MPTEXgraphictrue}}

\def\setMPtext#1#2%
  {%\forceMPTEXgraphic
   \convertargument#2\to\ascii
   \setevalue{\@@MPT#1}{\ascii}}

\def\MPtext  #1{\getvalue{\@@MPT#1}} 
\def\MPstring#1{"\getvalue{\@@MPT#1}"} 
\def\MPbetex #1{btex \getvalue{\@@MPT#1} etex}

%D Unfortunately \METAPOST\ does not have \CMYK\ support 
%D built in, but by means of specials we can supply the 
%D information needed to handle them naturaly. 

\newif\ifMPcmyk \MPcmyktrue 

\appendtoks
  cmykcolors := \ifMPcmyk true \else false \fi ;   
\to \MPinitializations 

%D In order to communicate conveniently with the \TEX\ 
%D engine, we introduce some typesetting variables. 

\startuseMPgraphic{init data}
  color OverlayColor, OverlayLineColor ;
  %
  OverlayWidth     := \overlaywidth ; 
  OverlayHeight    := \overlayheight ; 
  OverlayDepth     := \overlayheight ; 
  OverlayColor     := \MPcolor{\overlaycolor} ; 
  OverlayLineWidth := \overlaylinewidth ;
  OverlayLineColor := \MPcolor{\overlaylinecolor} ; 
  %
  BaseLineSkip := \the\baselineskip ;
  LineHeight   := \the\baselineskip ; 
  BodyFontSize := \the\bodyfontsize ;
  %
  StrutHeight := \strutheight ;
  StrutDepth  := \strutdepth ;
  %
  CurrentWidth  := \the\hsize ;
  CurrentHeight := \the\vsize ;
  %
  EmWidth  := \the\fontdimen6\font ;
  ExHeight := \the\fontdimen5\font ;
  % 
  PageNumber     := \the\realpageno ;
  RealPageNumber := \the\pageno ;
  LastPageNumber := \lastpage ; 
\stopuseMPgraphic

\appendtoks 
  \includeMPgraphic{init data} 
\to \MPinitializations

% this will become (more efficient) 
%
% \startuseMPgraphic{init data}
%   tx1 := \the\baselineskip ;
%   tx2 := \the\baselineskip ; 
%   tx3 := \the\bodyfontsize ;
%   tx4 := \strutheight ;
%   tx5 := \strutdepth ;
%   tx6 := \the\hsize ;
%   tx7 := \the\vsize ;
%   tx8 := \the\fontdimen6\font ;
%   tx9 := \the\fontdimen5\font ;
% \stopuseMPgraphic
% 
% def map_tx_variables = 
%   BaseLineSkip  := tx1 ;
%   LineHeight    := tx2 ;
%   BodyFontSize  := tx3 ;
%   StrutHeight   := tx4 ;
%   StrutDepth    := tx5 ;
%   CurrentWidth  := tx6 ;
%   Currentheight := tx7 ;
%   EmWidth       := tx8 ;
%   ExHeight      := tx9 ;
% enddef ; 
%
% extra_begin_fig .... 

%D Alas, the prologue settings differ per driver. 

\ifx\undefined\MPprologues \def\MPprologues{0} \fi 

\appendtoks 
  prologues := \MPprologues ; 
\to \MPinitializations

\appendtoks
  \def\MPprologues{0}%
  \def\MPOSTdriver{dvips}%
\to \everyresetspecials

%D \macros 
%D   {PDFMPformoffset}
%D
%D In \PDF, forms are clipped and therefore we have to take 
%D precautions to get this right. Since this is related to 
%D objects, we use the same offset as used there.  

\def\PDFMPformoffset{\objectoffset}

%D \macros 
%D   {insertMPfile}
%D
%D Bypassing the special driver and figure mechanism is not
%D that nice but saves upto 5\% time in embedding \METAPOST\
%D graphics by using the low level \PDF\ converter directly,
%D given of course that we use \PDFTEX. As a result we need to
%D fool around with the object trigger. 

\def\insertMPfile#1#2%
  {\ifx\pdfoutput\undefined 
     \doinsertMPfile{#1}%   
   \else\ifcase\pdfoutput   
     \doinsertMPfile{#1}%  
   \else                   
     \doiffileelse{#1}    
       {{\chardef\makeMPintoPDFobject=2 % in order to handle specials 
         \convertMPtoPDF{#1}{1}{1}}}
       {\doinsertMPfile{#1}}%
   \fi\fi}

%D We also take care of disabling fancy figure features, that
%D can terribly interfere when dealing with symbols, 
%D background graphics and running (postponed) graphics. 
%D You won't believe me if I tell you what funny side effects 
%D can occur. One took me over a day to uncover when 
%D processing the screen version of the \METAFUN\ manual. 

\def\doinsertMPfile#1%
  {\externalfigure
     [#1]
     [\c!type=\c!mps,\c!object=\v!nee,
      \c!reset=\v!ja,\c!symbool=\v!ja,
      \c!maxbreedte=,\c!maxhoogte=,
      \c!kader=\v!uit,\c!achtergrond=]}

\protect \endinput

% also: 
%
% linecap  := rounded ;
% linejoin := rounded ; 
% drawoptions () ;