%D \module
%D   [       file=meta-txt,
%D        version=2000.07.06,
%D          title=\METAPOST\ Graphics,
%D       subtitle=Text Tricks,
%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.

%D See comments in the \MKIV\ module. This is an upgraded version for \LMTX,
%D where we can so some things nicer.

\unprotect

%D Text in shapes. Here we use the option to prune a parshape when a new paragraph
%D is seen. It's an experimental feature so I need to keep an eye on how it evolves.
%D This time we combine \TEX, \METAPOST\ and \LUA, so we do't need a temporary file
%D to communicate from \METAPOST\ to \TEX. We just store information in \LUA\ tables.

\ifdefined\startshapetext \else
    \writestatus{system}{something is wrong here}
\fi

%D Following:

% \doifundefined{RotFont}{\definefont[RotFont][RegularBold*default]}
%
% \unexpanded\def\getfollowtoken#1%
%  {\hbox\bgroup
%     \strut
%     \ctxlua{mp.follow_text(#1)}%
%   \egroup}

\definefontfeature[mp:tp][liga=no]

% if unknown RotPath  : path    RotPath  ; RotPath  := origin ; fi ;
% if unknown TraceRot : boolean TraceRot ; TraceRot := false  ; fi ;
% if unknown ExtraRot : numeric ExtraRot ; ExtraRot := 0      ; fi ;
% if al < len[n]:
%    RotPath := RotPath scaled ((len[n]+ExtraRot)/al) ;
%    al := arclength RotPath ;
% fi ;
% if TraceRot :
%    draw RotPath withpen pencircle scaled 1pt withcolor blue ;
% fi ;
% if TraceRot :
%     draw boundingbox currentpicture withpen pencircle scaled .25pt withcolor blue ;
% fi ;

\protected\def\dofollowtokens#1#2%
  {\dontleavehmode
   \vpack\bgroup
   \forgetall
   \dontcomplain
   \addff{mp:tp}%
   \startMPcode
      \includeMPgraphic{followtokens}
      draw lmt_followtext [ path = RotPath, text = "#2", spread = #1 ] ;
   \stopMPcode
   \egroup}

\protected\def\followtokens        {\dofollowtokens{true}}
\protected\def\followtokenscentered{\dofollowtokens{false}}

%D Fuzzy counters:

\startuseMPgraphic{fuzzycount}
    begingroup
        save height, span, drift, d, cp ;
        height := 3/ 5 * LineHeight ;
        span   := 1/ 3 * height ;
        drift  := 1/10 * height ;
        pickup pencircle scaled (1/12 * height) ;
        def d = (uniformdeviate drift) enddef ;
        for i := 1 upto \MPvar{n} :
            draw
                if (i mod 5)=0 : ((-d - 4.5span,d) -- (d -0.5span,height - d))
                else           : ((-d,          d) -- (d,         height - d)) fi
                shifted (span*i,d-drift) ;
        endfor;
        picture cp ; cp := currentpicture ; % for readability
        setbounds currentpicture to
            (llcorner cp shifted (0,-ypart llcorner cp) --
             lrcorner cp shifted (0,-ypart lrcorner cp) --
             urcorner cp                                --
             ulcorner cp                                -- cycle) ;
    endgroup ;
\stopuseMPgraphic

\setupMPvariables
  [fuzzycount]
  [n=10]

\protected\def\fuzzycount#1%
  {\dontleavehmode\bgroup
     \tx
     \useMPgraphic{fuzzycount}{n=#1}%
   \egroup}

\defineconversion[fuzzy][\fuzzycount]

%D English rules:

\setupMPvariables
  [EnglishRule]
  [height=1ex,
   width=\localhsize,
   color=darkgray]

\defineblank
  [EnglishRule]
  [medium]

\startuniqueMPgraphic{EnglishRule}{height,width,color}
    x1 = 0 ; x3 = \MPvar{width} ; x2 = x4 = .5x3 ;
    y1 = y3 = 0 ; y2 = -y4 = \MPvar{height} / 2 ;
    fill z1 .. z2 .. z3 & z3 .. z4 .. z1 & cycle withcolor \MPvar{color} ;
\stopuniqueMPgraphic

\protected\def\EnglishRule
  {\startlinecorrection[EnglishRule]%
     \setlocalhsize
     \noindentation
     \reuseMPgraphic{EnglishRule}%
   \stoplinecorrection}

%D Tight text (for old times sake): the following macro returns a tight bound
%D character sequence.
%D
%D \useMPlibrary[txt]
%D
%D \startlinecorrection
%D \TightText{\ss\bf 123}{0cm}{3cm}{red}
%D \stoplinecorrection

\protected\def\TightText#1#2#3#4%
  {\hpack
     {\startMPcode
        picture p ; p := image (graphictext "#1" withfillcolor red) ;
        draw p xsized #2 ysized #3 withcolor \MPcolor{#4} ;
      \stopMPcode}}

\protected\def\TightText#1#2#3#4%
  {\dontleavehmode
   \startMPcode
      draw outlinetext.f ("#1") (\iftok{#4}\emptytoks \else withcolor \MPcolor{#4} \fi)
        \iftok{#2}\emptytoks \else xsized #2 \fi
        \iftok{#3}\emptytoks \else ysized  #3 \fi
      ;
   \stopMPcode}

\protect

\continueifinputfile{meta-imp-txt.mkxl}

\setupbodyfont[pagella,10pt]

% \useMPlibrary[txt]

\starttext

%D Shapes:

\startuseMPgraphic{test 1}
    path p ; p := fullcircle scaled 6cm ;

    build_parshape(p,BodyFontSize/2,0,0,LineHeight,StrutHeight,StrutDepth,StrutHeight) ;

    draw p withpen pencircle scaled 1pt ;
\stopuseMPgraphic

\startuseMPgraphic{test 2}
    path p ; p := fullsquare rotated 45 scaled 5cm ;

    build_parshape(p,BodyFontSize/2,0,0,LineHeight,StrutHeight,StrutDepth,StrutHeight) ;

    draw p withpen pencircle scaled 1pt ;
\stopuseMPgraphic

\startuseMPgraphic{test 3}
    numeric w, h ; w := h := 6cm ;
    path p ; p := (.5w,h) -- (0,h) -- (0,0) -- (w,0) &
        (w,0) .. (.75w,.5h) .. (w,h) & (w,h) -- cycle ;

    build_parshape(p,BodyFontSize/2,0,0,LineHeight,StrutHeight,StrutDepth,StrutHeight) ;

    draw p withpen pencircle scaled 1pt ;
\stopuseMPgraphic

\startuseMPgraphic{test 4}
    numeric w, h, o, d ;

    def shape = (o,o) -- (w-o,o) & (w-o,o) .. (.75w-o,.5h) ..
        (w-2o,h-o) & (w-2o,h-o) -- (o,h-o) -- cycle
    enddef ;

    d := BodyFontSize/2;

    w := h := 6cm ; o := d ; path p ; p := shape ;
    w := h := 6cm ; o := 0 ; path q ; q := shape ;

    build_parshape(p,q,d,d,LineHeight,StrutHeight,StrutDepth,StrutHeight) ;

    draw q withpen pencircle scaled 1pt ;
\stopuseMPgraphic

\defineoverlay[test 1][\useMPgraphic{test 1}]
\defineoverlay[test 2][\useMPgraphic{test 2}]
\defineoverlay[test 3][\useMPgraphic{test 3}]
\defineoverlay[test 4][\useMPgraphic{test 4}]

\startbuffer
\startshapetext[test 1,test 2,test 3,test 4]
    \setupalign[verytolerant,stretch,normal]%
    \samplefile{douglas} % Douglas R. Hofstadter
\stopshapetext
\startTEXpage[offset=10pt]
    \startcombination[2*2]
        {\framed[offset=overlay,frame=off,background=test 1]{\getshapetext}} {test 1}
        {\framed[offset=overlay,frame=off,background=test 2]{\getshapetext}} {test 2}
        {\framed[offset=overlay,frame=off,background=test 3]{\getshapetext}} {test 3}
        {\framed[offset=overlay,frame=off,background=test 4]{\getshapetext}} {test 4}
    \stopcombination
\stopTEXpage
\stopbuffer

\getbuffer

\startMPextensions
    boolean trace_parshape ; trace_parshape := true ;
\stopMPextensions

\getbuffer

%D Fuzzycount (maybe handy):

\startitemize[fuzzy,nostopper]
    \startitem This is real fuzzy. \stopitem
    \startitem But it can be even more fuzzier. \stopitem
    \startitem And how about this. \stopitem
\stopitemize

\EnglishRule

\startitemize[continue,broad]
    \startitem This is real fuzzy. \stopitem
    \startitem But it can be even more fuzzier. \stopitem
    \startitem And how about this. \stopitem
\stopitemize

%D Tight text (manual stuff):

\ruledhbox{\TightText{oeps wat doet dit}{10cm}{1cm}{red}}   \blank
\ruledhbox{\TightText{oeps wat doet dit}{10cm}{}   {green}} \blank
\ruledhbox{\TightText{oeps wat doet dit}{}    {1cm}{blue}}  \blank
\ruledhbox{\TightText{oeps wat doet dit}{}    {}   {}}      \blank

%D Old fashioned:

\startuseMPgraphic{followtokens}
    path RotPath ; RotPath := reverse halfcircle xyscaled 3cm  ;
    draw RotPath ;
\stopuseMPgraphic

\startTEXpage
    \followtokens{{\hskip1em}some text{\hskip1em}}
\stopTEXpage

\startTEXpage
    \followtokenscentered{{\hskip1em}some text{\hskip1em}}
\stopTEXpage

\stoptext