path: root/macros/optex/base/graphics.opm

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

\_codedecl \inspic {Graphics <2021-07-16>} % 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 -----------------------------

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

\_def\_picparams{}

\_public \inspic ;

   \_doc -----------------------------
   Inkscape can save a picture to `*.pdf` file and labels for the picture
   to `*.pdf_tex` file. The second file is in \LaTeX/ format (unfortunately)
   and it is intended to read immediately after `*.pdf` is included
   in order to place labels of this picture in the same font as the 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` tokens list and it is used
   locally 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
  \_tmptoks={#1}%
  \_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{\_the\_tmptoks}\_hss}%
  \_def\_inkscanpage#1page=#2,#3\_end{\_ifx,#2,\_else\_def\_picparams{page#2}\_fi}%
  \_def\put(#1,#2)#3{\_nointerlineskip\_vbox to\_zo{\_vss\_hbox to\_zo{\_kern#1\_picwidth
      \_pdfsave\_hbox to\_zo{#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 to\_zo{\_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``{<x-scale>}{<y-scale>}` and \`\pdfrotate``{<degrees>}`
   macros are implemented by `\pdfsetmatrix`
   primitive. We need to know the values of sin, cos function in
   the `\pdfrotate`. 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``{<transformation>}{<text>}`
   is copied from OPmac trick 0046.\nl
   The \`\rotbox``{<degrees>}{<text>}` is a combination of
   `\rotsimple` from OPmac trick 0101 and the `\transformbox`.
   Note, that `\rotbox{-90}` puts the rotated text to the height of the outer
   box (depth is zero) because code from `\rotsimple` is processed.
   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 width\_zo
   \_setbox0=\_hbox{\_box0}\_ht0=\_zo \_dp0=\_zo
   \_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=\_zo \_dp0=\_zo \_ht0=\_zo
                  \_pdfsave\_pdfrotate{#1}\_box0\_pdfrestore\vfil}%
   \_kern\_tmpdim
}}
\_public \transformbox \rotbox ;

   \_doc ---------------------------
   \`\_scantwodimens` scans two objects with the syntactic rule `<dimen>`
   and returns `{<number>}{<number>}` in `sp` unit.
   \nl
   \`\puttext` `<right> <up>{<text>}` puts the `<text>` to desired place:
   From current point moves <down> and <right>, puts the <text> and returns
   back. The current point is unchanged after this macro ends.
   \nl
   \`\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 a natural dimension.
   \nl
   \`\backgroundpic``{<image-file>}` puts the image to
   the background of each page. It is used in the \~`\slides` style, for example.
   \_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>\_zo \_vskip-\_prevdepth \_relax \_fi
      \_nointerlineskip
   \_fi
   \_wd0=\_zo \_ht0=\_zo \_dp0=\_zo
   \_vbox to\_zo{\_kern-\_dimen2 \_hbox to\_zo{\_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 -----------------------------
   \`\_circle``{<x>}{<y>}` creates an ellipse with `<x>` axis and `<y>` axis.
   The origin is in the center.
   \nl
   \`\_oval``{<x>}{<y>}{<roundness>}` creates an oval with `<x>`, `<y>` size and with
   the given `<roundness>`. The real size is bigger by 2`<roundness>`. The
   origin is at the left bottom corner.
   \nl
   \`\_mv``{<x>}{<y>}{<curve>}` moves current point to `<x>`, `<y>`, creates the
   `<curve>` and returns the current point back.
   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``{<text>}` is an example of \^`\_oval` usage.\nl
   The \`\incircle``{<text>}` is an example of \^`\_circle` usage.\nl
   The \`\ratio`, \`\lwidth`, \`\fcolor`, \`\lcolor`, \`\shadow` and \`\overlapmargins`
   are parameters, they can be set by user in optional brackets `[...]`.
   For example `\fcolor=\Red` does `\_let\_fcolorvalue=\Red` and it means
   filling color.\nl
   The \`\_setflcolors` uses the \^`\_setcolor` macro to separate filling (non-stroking)
   color and stroking color.
   \_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##2##3{##1 ##2}%
   \_edef#1{\_fcolorvalue}%
   \_def\_setcolor##1##2##3{##1 ##3}%
   \_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{\_egroup % of \setbox0=\hbox\bgroup
   \_ifdim\_vvkern=\_zo \_else \_ht0=\_dimexpr\_ht0+\_vvkern \_relax
                               \_dp0=\_dimexpr\_dp0+\_vvkern \_relax \_fi
   \_ifdim\_hhkern=\_zo \_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 to\_zo{\_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 {\_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=\_zo \_dimen1=\_zo
   \_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=\_zo \_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 -----------------------------
   Just before defining shadows, which require special graphics states, we
   define means for managing these graphics states. This is important, because
   otherwise our use of `\pdfpageresources` register might clash with other
   packages (TikZ) or even with our other usage (slides).

   The macro \`\addextgstate``<PDF name> <PDF dictionary>` shall be used for
   adding more graphics states. It must be used {\em after} `\dump`. First use
   of it detects PGF/TikZ and either uses its mechanism or defines our own. Our
   mechanism is very similar though -- use single `/ExtGState` dictionary for all
   pages (`\pdfpageresources` just points to it).
   \_cod -----------------------------

\_def\_initpageresources{%
   \_glet\_initpageresources=\_relax
   \_ifcsname pgf@sys@addpdfresource@extgs@plain\_endcsname
      % TikZ loaded
      \_global\_slet{_addextgstate}{pgf@sys@addpdfresource@extgs@plain}%
   \_else
      % TikZ not loaded
      \_pdfobj reserveobjnum% not to be used in iniTeX
      \_xdef\_extgstatesobj{\_the\_pdflastobj}%
      \_expanded{\_global\_pdfpageresources={/ExtGState \_extgstatesobj\_space 0 R}}%
      \_global\_addto\_byehook{\_immediate\_pdfobj useobjnum\_extgstatesobj {<<\_extgstates>>}}%
      \_gdef\_extgstates{}%
      \_gdef\_addextgstate##1{\_xdef\_extgstates{\_extgstates\_space##1}}%
   \_fi
}
% first initialize page resources, then execute new meaning of itself
\_def\_addextgstate#1{\_initpageresources \_addextgstate{#1}}

\_public \addextgstate ;

   \_doc -----------------------------
   A shadow effect is implemented here. The shadow is equal to the
   silhouette of the given path in a 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

\_def\_insertshadowresources{%
   \_addextgstate{/op1 <</ca \_shadowdarknessA>>}%
   \_addextgstate{/op2 <</ca \_shadowdarknessB>>}%
   \_glet\_insertshadowresources=\_relax
}

   \_doc -----------------------------
   The \`\_doshadow``{<curve>}` does the shadow effect.
   \_cod -----------------------------

\_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 the `<curve>` shifted by the `<x>`, `<y>`. The `<text>` is typeset
   when such clipping path is active. Dimensions are given by bp without the unit here.
   The macros \`\clipinoval` `<x> <y> <width> <height> {<text>}` and
   \`\clipincircle` `<x> <y> <width> <height> {<text>}` are defined here.
   These macros 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=\_zo
          \_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}}%
}
\_public \clipinoval \clipincircle ;


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

The \^`\inspic` is defined by `\pdfximage` and `\pdfrefximage` primitives.
If you want to use one picture more than once in your document, then the
following code is recommended:
\begtt \catcode`\<=13
\newbox\mypic
\setbox\mypic = \hbox{\picw=3cm \inspic{<picture>}}

My picture: \copy\mypic, again my picture: \copy\mypic, etc.
\endtt
This code downloads the picture data to the PFD output only once (when
`\setbox` is processed). Each usage of `\copy\mypic` puts only a pointer to
the picture data in the PDF.

If you want to copy the same picture in different sizes, then choose
a \"basic size" used in `\setbox` and all different sizes can be realized by
the \^`\transformbox{<transformation>}{\copy\mypic}`.

\_endinput

2021-07-16: \inoval, \incircle are more simple, using attribitecolor features
2021-03-19: \inkinspic: pictures in subdirectories, bug fixed
2020-12-21: \puttext: \box0 in goup, bugfix
2020-04-12: \_public \clipinoval \clipincircle ; added, bug fixed