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%% This is part of OpTeX project, see http://petr.olsak.net/optex

\_codedecl \inspic {Graphics <2020-03-29>} % preloaded in format

   \_doc -----------------------------
   `\inspic` accepts old syntax `\inspic <filename><space>`
   or new syntax `\inspic{<filename>}`. So, we need to define
   two auxiliary macros `\_inspicA` and `\_inspicB`.

   You can include more `\pdfximage` parameters (like `page<number>`)
   in the `\_picparams` macro.

   All `\inspic` macros are surrounded in `\hbox` in order user can
   write `\moveright\inspic ...` or something similar.
   \_cod \_fin -----------------------

\_def\_inspic{\_hbox\_bgroup\_isnextchar\_bgroup\_inspicB\_inspicA}
\_def\_inspicA #1 {\_inspicB {#1}}
\_def\_inspicB #1{%
   \_pdfximage \_ifdim\_picwidth=0pt  \_else width\_picwidth\_fi 
               \_ifdim\_picheight=0pt \_else height\_picheight\_fi 
               \_picparams {\_the\_picdir#1}%
   \_pdfrefximage\_pdflastximage\_egroup}

\_def\_picparams{}

\_public \inspic ;

   \_doc -----------------------------
   Inkscape is able to save a picture to `*.pdf` file and labels for the ficture
   to `*.pdf_tex` file. The second file is in \LaTeX/ format and it is intended to read 
   immediately it after `*.pdf` in included in order to place labels of this ficture in
   the same font as document is printed. 
   We need to read this \LaTeX/ file by plain \TeX/ macros when `\inkinspic` is used. 
   These macros are stored in the `\_inkdefs` toknes list and it is used
   localy in the group. The solution is borrowed from OPmac trick 0032. 
   \_cod -----------------------------

\_def\_inkinspic{\_hbox\_bgroup\_isnextchar\_bgroup\_inkinspicB\_inkinspicA}
\_def\_inkinspicA #1 {\_inkinspicB {#1}}
\_def\_inkinspicB #1{%
  \_ifdim\_picwidth=0pt \_setbox0=\_hbox{\_inspic{#1}}\_picwidth=\_wd0 \_fi
  \_the\_inkdefs
  \_opinput {\_the\_picdir #1_tex}% file with labels
  \_egroup}

\_newtoks\_inkdefs  \_inkdefs={% 
  \_def\makeatletter#1\makeatother{}% 
  \_def\includegraphics[#1]#2{\_inkscanpage#1,page=,\_end \_inspic{#2}\_hss}% 
  \_def\_inkscanpage#1page=#2,#3\_end{\_ifx,#2,\_else\_def\_picparams{page#2}\_fi}% 
  \_def\put(#1,#2)#3{\_nointerlineskip\_vbox to0pt{\_vss\_hbox to0pt{\_kern#1\_picwidth 
      \_pdfsave\_hbox to0pt{#3}\_pdfrestore\_hss}\_kern#2\_picwidth}}% 
  \_def\begin#1{\_csname _begin#1\_endcsname}%
  \_def\_beginpicture(#1,#2){\_vbox\_bgroup
      \_hbox to\_picwidth{}\_kern#2\_picwidth \_def\end##1{\_egroup}}%
  \_def\_begintabular[#1]#2#3\end#4{%
      \_vtop{\_def\\{\_cr}\_tabiteml{}\_tabitemr{}\_table{#2}{#3}}}%
  \_def\color[#1]#2{\_scancolor #2,}% 
  \_def\_scancolor#1,#2,#3,{\_pdfliteral{#1 #2 #3 rg}}% 
  \_def\makebox(#1)[#2]#3{\_hbox to0pt{\_csname _mbx:#2\_endcsname{#3}}}% 
  \_sdef{_mbx:lb}#1{#1\_hss}\_sdef{_mbx:rb}#1{\_hss#1}\_sdef{_mbx:b}#1{\_hss#1\_hss}% 
  \_sdef{_mbx:lt}#1{#1\_hss}\_sdef{_mbx:rt}#1{\_hss#1}\_sdef{_mbx:t}#1{\_hss#1\_hss}% 
  \_def\rotatebox#1#2{\_pdfrotate{#1}#2}%
  \_def\lineheight#1{}%
  \_def\setlength#1#2{}%
}
\_public \inkinspic ;

   \_doc ----------------------------
   `\pdfscale` and `\pdfrotate` macros are implemented by `\pdfsetmatrix`
   primitive. or rotating we need to knos values of sin, cos function.
   We use Lua code for this.
   \_cod ----------------------------

\_def\_pdfscale#1#2{\_pdfsetmatrix{#1 0 0 #2}}

\_def\_gonfunc#1#2{%
   \_directlua{tex.print(string.format('\_pcent.4f',math.#1(3.14159265*(#2)/180)))}%
}
\_def\_sin{\_gonfunc{sin}}
\_def\_cos{\_gonfunc{cos}}

\_def\_pdfrotate#1{\_pdfsetmatrix{\_cos{#1} \_sin{#1} \_sin{(#1)-180} \_cos{#1}}}

\_public \pdfscale \pdfrotate ;

   \_doc -----------------------------
   The `\transformbox` is copied from OPmac trick 0046. The `\rotbox` is a
   combination of `\rotsimple` from OPmac trick 0101 and `\transformbox`.
   Note, that `\rotbox{-90}` puts the rotated text to the height of the outer 
   box (depth is zero) because code from `\rotsimple` is precessed. 
   But `\rotbox{-90.0}` puts the rotated text to
   the depth of the outer box (height is zero) because `\transformbox` is
   processed. 
   \_cod -----------------------------

\_def\_multiplyMxV #1 #2 #3 #4 {% matrix * (vvalX, vvalY) 
   \_tmpdim = #1\_vvalX \_advance\_tmpdim by #3\_vvalY 
   \_vvalY  = #4\_vvalY \_advance\_vvalY  by #2\_vvalX 
   \_vvalX = \_tmpdim 
} 
\_def\_multiplyMxM #1 #2 #3 #4 {% currmatrix := currmatrix * matrix 
   \_vvalX=#1pt \_vvalY=#2pt \_ea\_multiplyMxV \_currmatrix 
   \_edef\_tmpb{\_ea\_ignorept\_the\_vvalX\_space \_ea\_ignorept\_the\_vvalY}% 
   \_vvalX=#3pt \_vvalY=#4pt \_ea\_multiplyMxV \_currmatrix 
   \_edef\_currmatrix{\_tmpb\_space 
      \_ea\_ignorept\_the\_vvalX\_space \_ea\_ignorept\_the\_vvalY\_space}% 
} 
\_def\_transformbox#1#2{\_hbox{\_setbox0=\_hbox{{#2}}%
   \_dimendef\_vvalX 11 \_dimendef\_vvalY 12 % we use these variables
   \_dimendef\_newHt 13 \_dimendef\_newDp 14 % only in this group
   \_dimendef\_newLt 15 \_dimendef\_newRt 16 
   \_preptransform{#1}% 
   \_kern-\_newLt \_vrule height\_newHt depth\_newDp width0pt 
   \_setbox0=\_hbox{\_box0}\_ht0=0pt \_dp0=0pt 
   \_pdfsave#1\_rlap{\_box0}\_pdfrestore \_kern\_newRt}% 
} 
\_def\_preptransform #1{\_def\_currmatrix{1 0 0 1 }% 
   \_def\_pdfsetmatrix##1{\_edef\_tmpb{##1 }\_ea\_multiplyMxM \_tmpb\_unskip}%
   \_let\pdfsetmatrix=\_pdfsetmatrix #1% 
   \_setnewHtDp 0pt  \_ht0  \_setnewHtDp 0pt  -\_dp0 
   \_setnewHtDp \_wd0 \_ht0  \_setnewHtDp \_wd0 -\_dp0 
   \_protected\_def \_pdfsetmatrix {\_pdfextension setmatrix}%
   \_let\pdfsetmatrix=\_pdfsetmatrix
} 
\_def\_setnewHtDp #1 #2 {% 
   \_vvalX=#1\_relax \_vvalY=#2\_relax \_ea\_multiplyMxV \_currmatrix 
   \_ifdim\_vvalX<\_newLt \_newLt=\_vvalX \_fi \_ifdim\_vvalX>\_newRt \_newRt=\_vvalX \_fi 
   \_ifdim\_vvalY>\_newHt \_newHt=\_vvalY \_fi \_ifdim-\_vvalY>\_newDp \_newDp=-\_vvalY \_fi 
} 

\_def\_rotbox#1#2{%
   \_isequal{90}{#1}\_iftrue \_rotboxA{#1}{\_kern\_ht0 \_tmpdim=\_dp0}{\_vfill}{#2}%
   \_else \_isequal{-90}{#1}\_iftrue \_rotboxA{#1}{\_kern\_dp0 \_tmpdim=\_ht0}{}{#2}%
   \_else \_transformbox{\_pdfrotate{#1}}{#2}%
   \_fi \_fi
}
\_def\_rotboxA #1#2#3#4{\_hbox{\_setbox0=\hbox{{#4}}#2%
   \_vbox to\_wd0{#3\_wd0=0pt \_dp0=0pt \_ht0=0pt
                  \_pdfsave\_pdfrotate{#1}\_box0\_pdfrestore\vfil}%
   \_kern\_tmpdim
}}
\_public \transformbox \rotbox ;

   \_doc ---------------------------
   The `\_scantwodimens` scans two objects with the syntactic rule <dimen>
   and returns `{<number>}{<number>}` in sp unit.

   The `\puttext <right> <up>{<text>}` puts the <text> to desired place:
   From current point moves <down> and <right>, puts the <text> and returns
   back. The cuuren tpoint is unchanged after this macro ends.
   
   The  `\putpic <right> <up> <width> <height> {<image-file>}`
   does `\puttext` with the image scaled to desired <width> and <height>.
   If <with> or <height> is zero, natural dimension is used.
   The `\nospec` is a shortcut to such natural dimension.
   \_cod ---------------------------

\_def\_scantwodimens{%
   \_directlua{tex.print(string.format('{\_pcent d}{\_pcent d}',
               token.scan_dimen(),token.scan_dimen()))}%
}

\_def\_puttext{\_ea\_ea\_ea\_puttextA\_scantwodimens}
\_def\_puttextA#1#2#3{\_setbox0=\_hbox{{#3}}\_dimen1=#1sp \_dimen2=#2sp \_puttextB}
\_def\_puttextB{%
   \_ifvmode
      \_ifdim\_prevdepth>0pt \_vskip-\_prevdepth \_relax \_fi 
      \_nointerlineskip 
   \_fi
   \_wd0=0pt \_ht0=0pt \_dp0=0pt
   \_vbox to0pt{\_kern-\_dimen2 \_hbox to0pt{\_kern\_dimen1 \_box0\_hss}\_vss}}

\_def\_putpic{\_ea\_ea\_ea\_putpicA\_scantwodimens}
\_def\_putpicA#1#2{\_dimen1=#1sp \_dimen2=#2sp \_ea\_ea\_ea\_putpicB\_scantwodimens}
\_def\_putpicB#1#2#3{\_setbox0=\_hbox{\_picwidth=#1sp \_picheight=#2sp \_inspic{#3}}\_puttextB}

\_newbox\_bgbox
\_def\_backgroundpic#1{%
   \_setbox\_bgbox=\_hbox{\_picwidth=\_pdfpagewidth \_picheight=\_pdfpageheight \_inspic{#1}}%
   \_pgbackground={\_copy\_bgbox}
}
\_def\nospec{0pt}
\_public \puttext \putpic \backgroundpic ;

   \_doc -----------------------------
   You can use expandable `\_bp{<dimen>}` convertor from
   \TeX/ `<dimen>` (or from an expression accepted by
   `\dimexpr` primitive) to a decimal value in big points
   (used as natural unit in the PDF format). So, you can write, for example:
   \begtt
   \pdfliteral{q \_bp{.3\hsize-2mm} \_bp{2mm} m 0 \_bp{-4mm} l S Q}
   \endtt
   You can use expandable `\_expr{<expression>}` for analogical purposes.
   The `<expression>` can include `+-*/()` and decimal numbers in common syntax.
   \_cod -----------------------------

\_def\_decdigits{3} % digits after decimal point in \_bp and \_expr outputs.
\_def\_pttopb{%
   \_directlua{tex.print(string.format('\_pcent.\_decdigits f',
               token.scan_dimen()/65781.76))}%  pt to bp conversion
}
\def\_bp#1{\_ea\_pttopb\_dimexpr#1\_relax}
\def\_expr#1{\_directlua{tex.print(string.format('\_pcent.\_decdigits f',#1))}}

   \_doc -----------------------------
   `\)circle<x><y>` creates an ellipse with `<x>` axis and `<y>` axix.
   The origin is in the center.
   `\_oval<x><y><roudness>` creates an oval with `<x>`, `<y>` size and with 
   given `<roundness>`. The real size is bigger by 2`<roundness>`. The
   orgigin is at the left bottom corner.
   `\_mv<x><y>{<curve>}` moves current point to `<x>`, `<y>`, crates the
   `<curve>` and retuns back the current point.
   All these macros are fully expandable and they can be used in the
   `\pdfliteral` argument.
   \_cod -----------------------------

\def\_circle#1#2{\_expr{.5*(#1)} 0 m 
   \_expr{.5*(#1)} \_expr{.276*(#2)} \_expr{.276*(#1)} \_expr{.5*(#2)} 0 \_expr{.5*(#2)} c
   \_expr{-.276*(#1)} \_expr{.5*(#2)} \_expr{-.5*(#1)} \_expr{.276*(#2)} \_expr{-.5*(#1)} 0 c
   \_expr{-.5*(#1)} \_expr{-.276*(#2)} \_expr{-.276*(#1)} \_expr{-.5*(#2)} 0 \_expr{-.5*(#2)} c
   \_expr{.276*(#1)} \_expr{-.5*(#2)} \_expr{.5*(#1)} \_expr{-.276*(#2)} \_expr{.5*(#1)} 0 c h}

\def\_oval#1#2#3{0 \_expr{-(#3)} m \_expr{#1} \_expr{-(#3)} l 
    \_expr{(#1)+.552*(#3)} \_expr{-(#3)} \_expr{(#1)+(#3)} \_expr{-.552*(#3)} 
                                                           \_expr{(#1)+(#3)} 0 c 
    \_expr{(#1)+(#3)} \_expr{#2} l
    \_expr{(#1)+(#3)} \_expr{(#2)+.552*(#3)} \_expr{(#1)+.552*(#3)} \_expr{(#2)+(#3)}
                                             \_expr{#1} \_expr{(#2)+(#3)} c
    0 \_expr{(#2)+(#3)} l
    \_expr{-.552*(#3)} \_expr{(#2)+(#3)} \_expr{-(#3)} \_expr{(#2)+.552*(#3)} 
                                         \_expr{-(#3)} \_expr{#2} c
    \_expr{-(#3)} 0 l
    \_expr{-(#3)} \_expr{-.552*(#3)} \_expr{-.552*(#3)} \_expr{-(#3)}  0 \_expr{-(#3)} c h}

\def\_mv#1#2#3{1 0 0 1 \_expr{#1} \_expr{#2} cm #3 1 0 0 1 \_expr{-(#1)} \_expr{-(#2)} cm}

   \_doc -----------------------------
   The `\inoval` is an example of `\_oval` usage.
   The `\incircle` is an example of `\_circle` usage.
   \_cod -----------------------------

\_newdimen \_lwidth 
\_def\_fcolor{\_let\_fcolorvalue}
\_def\_lcolor{\_let\_lcolorvalue}
\_def\_shadow{\_let\_shadowvalue}
\_def\_overlapmargins{\_let\_overlapmarginsvalue}
\_def\_ratio{\isnextchar ={\_ratioA}{\_ratioA=}}
\_def\_ratioA =#1 {\_def\_ratiovalue{#1}}
\_def\_touppervalue#1{\_ifx#1n\_let#1=N\_fi}

\_def\_setflcolors#1{% use only in a group
   \_def\_setcolor##1{##1}%
   \_def\_fillstroke##1##2{##1}%
   \_edef#1{\_fcolorvalue}%
   \_def\_fillstroke##1##2{##2}%
   \_edef#1{#1\_space\_lcolorvalue\_space}%
}

\_optdef\_inoval[]{\_vbox\_bgroup
   \_roundness=2pt \_fcolor=\Yellow \_lcolor=\Red \_lwidth=.5bp 
   \_shadow=N \_overlapmargins=N \_hhkern=0pt \_vvkern=0pt
   \_the\_ovalparams \_relax \_the\_opt \_relax
   \_touppervalue\_overlapmarginsvalue \_touppervalue\_shadowvalue
   \_ifx\_overlapmarginsvalue N%
      \_advance\_hsize by-2\_hhkern \_advance\_hsize by-2\_roundness \_fi
   \_setbox0=\_hbox\_bgroup\_bgroup \_aftergroup\_inovalA \_kern\_hhkern \_let\_next=%
}
\_def\_inovalA{\_isnextchar\_colorstackpop\_inovalB\_inovalC}
\_def\_inovalB#1{#1\_isnextchar\_colorstackpop\_inovalB\_inovalC}
\_def\_inovalC{\_egroup % of \setbox0=\hbox\bgroup
   \_ifdim\_vvkern=0pt \_else \_ht0=\_dimexpr\_ht0+\_vvkern \_relax
                              \_dp0=\_dimexpr\_dp0+\_vvkern \_relax \_fi
   \_ifdim\_hhkern=0pt \_else \_wd0=\_dimexpr\_wd0+\_hhkern \_relax \_fi
   \_ifx\_overlapmarginsvalue N\_dimen0=\_roundness \_dimen1=\_roundness
   \_else                      \_dimen0=-\_hhkern   \_dimen1=-\_vvkern \_fi 
   \_setflcolors\_tmp
   \_hbox{\_kern\_dimen0 
      \_vbox to0pt{\_kern\_dp0 
         \_ifx\_shadowvalue N\_else 
            \_edef\_tmpb{{\_bp{\_wd0+\_lwidth}}{\_bp{\_ht0+\_dp0+\_lwidth}}{\_bp{\_roundness}}}%
            \_doshadow\_oval 
         \_fi
         \_pdfliteral{q \_bp{\_lwidth} w \_tmp 
            \_oval{\_bp{\wd0}}{\_bp{\_ht0+\_dp0}}{\_bp{\_roundness}} B Q}\_vss}%
      \_ht0=\_dimexpr\_ht0+\_dimen1 \_relax \_dp0=\_dimexpr\_dp0+\_dimen1 \_relax
      \_box0 
      \_kern\_dimen0}%
   \_egroup % of \vbox\bgroup
}
\_optdef\_incircle[]{\_vbox\_bgroup
   \_ratio=1 \_fcolor=\Yellow \_lcolor=\Red \_lwidth=.5bp 
   \_shadow=N \_overlapmargins=N \_hhkern=3pt \_vvkern=3pt
   \_ea\_the \_ea\_circleparams \_space \_relax
   \_ea\_the \_ea\_opt \_space \_relax
   \_touppervalue\_overlapmarginsvalue \_touppervalue\_shadowvalue
   \_setbox0=\_hbox\_bgroup\_bgroup \_aftergroup\_incircleA \_kern\_hhkern \_let\_next=%
}
\_def\_incircleA {\_isnextchar\_colorstackpop\_incircleB\_incircleC}
\_def\_incircleB #1{#1\_isnextchar\_colorstackpop\_incircleB\_incircleC}
\_def\_incircleC {\_egroup % of \setbox0=\hbox\bgroup
   \_wd0=\dimexpr \_wd0+\_hhkern \_relax
   \_ht0=\dimexpr \_ht0+\_vvkern \_relax \_dp0=\dimexpr \_dp0+\_vvkern \_relax
   \_ifdim \_ratiovalue\_dimexpr \_ht0+\_dp0 > \_wd0
          \_dimen3=\_dimexpr \_ht0+\_dp0 \_relax  \_dimen2=\_ratiovalue\_dimen3
   \_else \_dimen2=\_wd0 \_dimen3=\_expr{1/\_ratiovalue}\_dimen2 \fi
   \_setflcolors\_tmp
   \_ifx\_overlapmarginsvalue N\_dimen0=0pt \_dimen1=0pt 
   \_else \_dimen0=-\hhkern \_dimen1=-\vvkern \_fi
   \_hbox{\_kern\dimen0 
      \_ifx\_shadowvalue N\_else 
         \_edef\_tmpb{{\_bp{\_dimen2+\_lwidth}}{\_bp{\_dimen3+\_lwidth}}{}}%
         \_doshadow\_circlet
      \_fi      
      \_pdfliteral{q \_bp{\_lwidth} w \_tmp \_mv{\_bp{.5\_wd0}}{\_bp{(\ht0-\dp0)/2}}
                                      {\_circle{\_bp{\_dimen2}}{\_bp{\_dimen3}} B} Q}%
      \_ifdim\_dimen1=0pt \_else 
           \_ht0=\dimexpr \_ht0+\_dimen1 \_relax \_dp0=\dimexpr \_dp0+\_dimen1 \_relax \_fi
      \_box0
      \_kern\_dimen0}
   \_egroup % of \vbox\bgroup
}
\_def\_circlet#1#2#3{\_circle{#1}{#2}}

\_public 
   \inoval \incircle \ratio \lwidth \fcolor \lcolor \shadow \overlapmargins ;

   \_doc -----------------------------
   A shadow effect is implemented here. The shadow is equal to the
   silhouette of the given path in gray-transparent color shifted by
   `\shadowmoveto` vector and with blurred boundary.
   A waistline with the width 2*`\shadowb` around the boundary is blurred.
   The `\shadowlevels` levels of transparent shapes is used for creating
   this effect. The `\shadowlevels+1/2` level is equal to the shifted given path.
   \_cod -----------------------------

\_def\_shadowlevels{9}         % number of layers for blurr effect
\_def\_shadowdarknessA{0.025}  % transparency of first shadowlevels/2 layers
\_def\_shadowdarknessB{0.07}   % transparency of second half of layers
\_def\_shadowmoveto{1.8 -2.5}  % vector defines shifting layer (in bp)
\_def\_shadowb{1}              % 2*shadowb = blurring area thickness

   \_doc -----------------------------
   The `\_pdfpageresources` primitive is used to define transparency.
   It does not work when used in a box. So, we use it at begining of
   output routine. The modification of output routine is done only once
   when the shadow effect is used first.
   \_cod -----------------------------

\_def\_insertshadowresources{%
   \_global\_addto\_begoutput{\_setshadowresources}%
   \_xdef\_setshadowresources{%
      \_pdfpageresources{/ExtGState 
      <<
      /op1  << /Type /ExtGState /ca \_shadowdarknessA >>
      /op2  << /Type /ExtGState /ca \_shadowdarknessB >>
      >>
      }%
   }%
   \_global\_let\_insertshadowresources=\_relax
}
\_def\_doshadow#1{\_vbox{%
    \_insertshadowresources
    \_tmpnum=\_numexpr (\_shadowlevels-1)/2 \_relax
    \_edef\_tmpfin{\_the\_tmpnum}%
    \_ifnum\_tmpfin=0 \_def\_shadowb{0}\_def\_shadowstep{0}%
    \_else \_edef\_shadowstep{\_expr{\_shadowb/\_tmpfin}}\_fi
    \_def\_tmpa##1##2##3{\_def\_tmpb
        {#1{##1+2*\_the\_tmpnum*\_shadowstep}{##2+2*\_the\_tmpnum*\_shadowstep}{##3}}}%
    \_ea \_tmpa \_tmpb
    \_def\_shadowlayer{%
        \_ifnum\_tmpnum=0 /op2 gs \_fi
        \_tmpb\_space f
        \_immediateassignment\_advance\_tmpnum by-1
        \_ifnum-\_tmpfin<\_tmpnum 
           \_ifx#1\_oval 1 0 0 1 \_shadowstep\_space \_shadowstep\_space cm \_fi 
           \_ea \_shadowlayer \_fi
    }%
    \_pdfliteral{q /op1 gs 0 g 1 0 0 1 \_shadowmoveto\_space cm  
       \_ifx#1\_circlet 1 0 0 1 \_expr{\_bp{.5\_wd0}} \_expr{\_bp{(\_ht0-\_dp0)/2}} cm 
       \_else  1 0 0 1 -\_shadowb\_space -\_shadowb\_space cm \_fi
       \_shadowlayer Q}
}}

   \_doc -----------------------------
   A generic macro `\clipinpath{<x>}{<y>}{<curve>}{<text>}` declares
   a clipping path by <curve> shifted by <x>, <y>. The <text> is typesset
   when such clipping path is active. Dimensions are given by bp without the unit here.
   Macros `\clipinoval <x> <y> <width> <height> {<text>}` and
   `\clipincircle <x> <y> <width> <height> {<text>}` are defined here.
   These marcos read normal \TeX/ dimensions in their parameters.
   \_cod -----------------------------

\_def\_clipinpath#1#2#3#4{% #1=x-pos[bp], #2=y-pos[bp], #3=curve, #4=text
   \_hbox{\setbox0=\hbox{{#4}}%
          \_tmpdim=\wd0 \wd0=0pt
          \_pdfliteral{q \_mv{#1}{#2}{#3 W n}}%
          \_box0\_pdfliteral{Q}\_kern\_tmpdim
   }%
}

\_def\_clipinoval {\_ea\_ea\_ea\_clipinovalA\_scantwodimens}
\_def\_clipinovalA #1#2{%
   \_def\_tmp{{#1/65781.76}{#2/65781.76}}%
   \_ea\_ea\_ea\_clipinovalB\_scantwodimens
}
\_def\_clipinovalB{\_ea\_clipinovalC\_tmp}
\_def\_clipinovalC#1#2#3#4{%
   \_ea\_clipinpath{#1-(#3/131563.52)+(\_bp{\_roundness})}{#2-(#4/131563.52)+(\_bp{\_roundness})}%
   {\_oval{#3/65781.76-(\_bp{2\_roundness})}{#4/65781.76-(\_bp{2\_roundness})}{\_bp{\_roundness}}}%
}
\_def\_clipincircle {\_ea\_ea\_ea\_clipincircleA\_scantwodimens}
\_def\_clipincircleA #1#2{%
   \_def\_tmp{{#1/65781.76}{#2/65781.76}}%
   \_ea\_ea\_ea\_clipincircleB\_scantwodimens
}
\_def\_clipincircleB#1#2{%
   \_ea\_clipinpath\_tmp{\_circle{#1/65781.76}{#2/65781.76}}%
}

\_endcode % -------------------------------------