mlib-pdf.mkiv / last modification: 2020-01-30 14:16
%D \module
%D   [       file=mlib-pdf,
%D        version=2008.03.25,
%D          title=\METAPOST\ Integrated Graphics,
%D       subtitle=Conversion to 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.

\unprotect

%D We use bit more code that needed because we want to limit the amount of boxing.

\registerctxluafile{mlib-pdf}{}

%D Some code is shared between MPLIB and MPS. The following variables are also
%D available for introspection and other purposes.

\ifdefined\MPwidth  \else \newdimen\MPwidth  \fi
\ifdefined\MPheight \else \newdimen\MPheight \fi

\ifdefined\MPllx    \else \newdimen\MPllx    \fi
\ifdefined\MPlly    \else \newdimen\MPlly    \fi
\ifdefined\MPurx    \else \newdimen\MPurx    \fi
\ifdefined\MPury    \else \newdimen\MPury    \fi

\ifdefined\MPbox    \else \newbox  \MPbox    \fi

\unexpanded\def\setMPboundingbox#1#2#3#4% at some point we might pass them as base or scaled points
  {\global\MPllx   #1\onebasepoint
   \global\MPlly   #2\onebasepoint
   \global\MPurx   #3\onebasepoint
   \global\MPury   #4\onebasepoint
   \global\MPwidth \dimexpr\MPurx-\MPllx\relax
   \global\MPheight\dimexpr\MPury-\MPlly\relax}

\unexpanded\def\resetMPboundingbox
  {\global\MPwidth \zeropoint
   \global\MPheight\zeropoint
   \global\MPllx   \zeropoint
   \global\MPlly   \zeropoint
   \global\MPurx   \zeropoint
   \global\MPury   \zeropoint}

\let\popMPboundingbox\relax

\unexpanded\def\pushMPboundingbox
  {\edef\popMPboundingbox
     {\global\MPwidth \the\MPwidth
      \global\MPheight\the\MPheight
      \global\MPllx   \the\MPllx
      \global\MPlly   \the\MPlly
      \global\MPurx   \the\MPurx
      \global\MPury   \the\MPury
      \relax}}

\unexpanded\def\repositionMPboxindeed
  {\setbox\MPbox\hpack\bgroup
     \kern-\MPllx
     \raise-\MPlly
     \box\MPbox
   \egroup}

\unexpanded\def\repositionMPbox
  {\ifzeropt\MPllx
     \ifzeropt\MPlly
       % okay
     \else
       \repositionMPboxindeed
     \fi
   \else
     \repositionMPboxindeed
   \fi}

\unexpanded\def\finalizeMPbox
  {\repositionMPbox
   \setbox\MPbox\vpack to \MPheight\bgroup
     \vfill
     \hsize\MPwidth
     \smashbox\MPbox
     \box\MPbox
   \egroup
   \wd\MPbox\MPwidth
   \ht\MPbox\MPheight}

% MPLIB specific:

\def\MPLIBtoPDF{\clf_mpflushliteral} % expanded

\unexpanded\def\startMPLIBtoPDF#1#2#3#4%
  {\meta_process_graphic_figure_start
   \dostarttagged\t!mpgraphic\empty
   \naturalhpack attr \imageattribute \plusone \bgroup
   \dousecolorparameter\s!black\forcecolorhack
   \setMPboundingbox{#1}{#2}{#3}{#4}%
   \setbox\MPbox\vpack\bgroup
 % \forgetall % already done elsewhere
   \noindent} % forces the proper cm in the backend

\unexpanded\def\stopMPLIBtoPDF
  {\egroup
   \finalizeMPbox
   \box\MPbox
   \egroup
   \dostoptagged
   \meta_process_graphic_figure_stop}

\def\MPLIBflushreset % This can (will) move to the Lua end.
  {\clf_mpflushreset}

%D Kind of special:
%
% test.mp:
%
% beginfig(1) fill fullcircle scaled 10cm withcolor red  ; endfig ;
% beginfig(2) draw fullcircle scaled  5cm withcolor blue ; endfig ;
% beginfig(3) draw textext("just some text")             ; endfig ;
%
% standalone pages:
%
% \starttext
%     \directMPgraphic{input "test.mp" ;}
% \stoptext

\let\normalstartMPLIBtoPDF\startMPLIBtoPDF
\let\normalstopMPLIBtoPDF \stopMPLIBtoPDF

\unexpanded\def\directstartMPLIBtoPDF{\startTEXpage\normalstartMPLIBtoPDF}
\unexpanded\def\directstopMPLIBtoPDF {\normalstopMPLIBtoPDF\stopTEXpage}

\unexpanded\def\directMPgraphic
  {\dodoublegroupempty\mlib_direct_graphic}

\def\mlib_direct_graphic#1#2% makes pages (todo: make boxes)
  {\meta_begin_graphic_group{#1}%
   \let\startMPLIBtoPDF\directstartMPLIBtoPDF
   \let\stopMPLIBtoPDF \directstopMPLIBtoPDF
   \meta_start_current_graphic
     \forgetall
     \edef\p_extensions{\MPinstanceparameter\s!extensions}%
     \normalexpanded{\noexpand\clf_mpgraphic
         instance        {\currentMPinstance}%
         format          {\currentMPformat}%
         data            {#2;}%
         initializations {\meta_flush_current_initializations}%
    \ifx\p_extensions\v!yes
         extensions      {\clf_getmpextensions{\currentMPinstance}}%
    \fi
         inclusions      {\meta_flush_current_inclusions}%
         definitions     {\meta_flush_current_definitions}%
         figure          {all}%
         method          {\MPinstanceparameter\c!method}%
     \relax}%
   \meta_stop_current_graphic
   \meta_end_graphic_group}

\protect \endinput