Lifespan lines in TeX

Question

I'm writing a document (written in plainTeX) about the lives of important mathematicians and physicists in human history.

Now I have a problem I'd like to tackle. I need to be able to visualize their lifespans (so that reader can see who was whose contemporary/coeval). Unfortunatelly, I'm not that skilled in making TeX's macros. Can anyone give me a hint how to do it?

Specifically, I imagine it would work this way:

\person{name}{surname}{year_of_birth}{year_of_death}
\person{name}{surname}{year_of_birth}{year_of_death}
...
\renderpeople

which would produce (for instance, with instances of Bach & Mozart)

Bach J.S.              |----------------|
Mozart A.                      |-----------------|
...
          |----------|-----------|----------|-----------|---------|
       1750        1800        1850       1900        1950      2000

Mainly, how would one implement rescaling of lines, so they would fit?

Answer 1

A quick hack in plain TeX using vanilla TeX. First the person data are collected and some values are calculated (minimal year, maximal year, width of names), then the collected person data are set and finally the whole time line is printed.

\newdimen\NameWidth
\NameWidth=0pt
\newcount\MinYear
\MinYear=100000
\newcount\MaxYear
\MaxYear=-100000
\newtoks\PersonData
\PersonData={}
\newdimen\ScaleWidth
\newdimen\ScaleUnit
\newcount\TempCount
\newdimen\TickMarkWidth
\TickMarkWidth=.4pt
\newdimen\TickMarkHeight
\TickMarkHeight=8pt
\newdimen\LineWidth
\LineWidth=.4pt
\newdimen\LastYearCorr

\def\person#1#2#3#4{%
  \setbox0=\hbox{\makeperson{#1}{#2}\personsep}%
  \ifdim\wd0>\NameWidth
    \NameWidth=\wd0 %
  \fi
  \ifnum#3<\MinYear
    \MinYear=#3\relax
  \fi
  \ifnum#4>\MaxYear
    \MaxYear=#4\relax
  \fi
  \ifnum#3>#4\relax
    \errmessage{#2 #1 has negative live span, born in #3 and died in #4}%
  \fi
  \PersonData=\expandafter{\the\PersonData
    \DoPerson{#1}{#2}{#3}{#4}%
  }%
}
\def\makeperson#1#2{#1, #2}%
\def\personsep{ }
\def\renderpeople{%
  \par
  \divide\MinYear by 50\relax
  \multiply\MinYear by 50\relax
  \advance\MaxYear by 49\relax 
  \divide\MaxYear by 50\relax  
  \multiply\MaxYear by 50\relax
  \ScaleWidth=\hsize
  \advance\ScaleWidth by -\NameWidth
  \setbox0=\hbox{$\textstyle\the\MaxYear$}%
  \LastYearCorr=.5\wd0 %
  \advance\ScaleWidth by -\LastYearCorr
  \ScaleUnit=\ScaleWidth
  \TempCount=\MaxYear   
  \advance\TempCount by -\MinYear
  \divide\ScaleUnit by \TempCount
  \ScaleWidth=\ScaleUnit
  \multiply\ScaleWidth by \TempCount
  \noindent
  \the\PersonData
  \ScaleLine
  \par
}
\def\DoPerson#1#2#3#4{%
  \hbox to \hsize{%
    \hbox to \NameWidth{%
      \makeperson{#1}{#2}%
      \hfill
      \personsep
    }%
    \hfill
    \hbox to \ScaleWidth{%
      \kern#3\ScaleUnit   
      \kern-\MinYear\ScaleUnit
      \SetTickMark
      \TempCount=#4\relax
      \advance\TempCount by -#3\relax
      \SetLine\TempCount
      \SetTickMark
      \hfill
    }%
    \kern\LastYearCorr
  }%
  \hskip0pt\relax
}
\def\ScaleLine{%
  \hbox to \hsize{%
    \hbox to \NameWidth{\hfill}%
    \hfill
    \hbox to \ScaleWidth{%
      \TempCount=\MinYear 
      \SetTickYearMark    
      \loop
      \ifnum\TempCount<\MaxYear
        \SetLine{50}%
        \advance\TempCount by 50 %
        \SetTickYearMark
      \repeat
    }%
    \kern\LastYearCorr
  }%
  \hskip0pt\relax
}
\def\SetTickYearMark{%
  \hbox to 0pt{%
    \hss
    $\mathsurround=0pt\relax
      \mathop{\vcenter{%
        \hrule width \TickMarkWidth
               height .5\TickMarkHeight
               depth .5\TickMarkHeight 
      }}\limits_{\textstyle\the\TempCount}%
    $%
    \hss
  }%
}   
\def\SetTickMark{%
  \hbox to 0pt{%  
    \hss
    $\mathsurround=0pt\vcenter{%
      \hrule width \TickMarkWidth
             height .5\TickMarkHeight
             depth .5\TickMarkHeight 
    }$%
    \hss
  }%
}   
\def\SetLine#1{%
  $\mathsurround=0pt\vcenter{%
    \hrule width#1\ScaleUnit  
           height.5\LineWidth 
           depth.5\LineWidth  
  }$%
}

\person{Pachelbel}{J.}{1653}{1706}
\person{Bach}{J. S.}{1685}{1750}  
\person{Mozart}{W. A.}{1756}{1791}
\person{Euler}{L.}{1707}{1783}

\renderpeople
\bye

Remarks:

• I would prefer e-TeX's \dimexpr and \numexpr if they are available; they are more comfortable. However divisions are different, because the \...expr are rounding the result.

• The powerful pgf/TikZ is available in plain TeX, too.

Answer 2

here is a similiar TeX solution:

\input pst-grad
\input pstricks-add
\newbox\TBox
\psset{gradbegin=white,gradend=lightgray}
\catcode`\@11\relax

\def\BoxText{\@ifnextchar[\BoxText@i{\BoxText@i[3cm]}}
\def\BoxText@i[#1]#2#3#4{%
  \emergencystretch=3em
  \setbox\TBox\vbox{\hsize #1 #4\par}
  \rput[t](#2){\psframebox[fillstyle=gradient]{\leavevmode\copy\TBox\relax}}%
  \pnode(#2|0,0){A}\pnode(#2){B}
  \ncline{->}{A}{B}%
  \uput*{0.5cm}[-90](A){#3}%
}
\catcode`\@12\relax

\pspicture(0,0.25)(2.5,-10)
\psset{xunit=5}
\psaxes[yAxis=false,Ox=1518]{|->}(0,0)(2.5,-10)% 
\BoxText[4cm]{1.1123,-5.5}{10.2.}{%
Hier muss jetzt irgendetwas hinkommen, was, weiss ich auch nicht genau}
\BoxText{.767,-2}{15.10.}{%
Hier muss jetzt irgendetwas hinkommen, was, weiss ich auch nicht genau}
\endpspicture


\pspicture(0,0.25)(2.5,-10)
\psset{xunit=5cm}
\psaxes[yAxis=false,Ox=1518]{|->}(0,0)(2.5,-10)%
\BoxText{.787,-5}{17.10.}{%
Hier muss jetzt irgendetwas hinkommen, was, weiss ich auch nicht genau}
\pnode(A){A0}
\BoxText{.767,-2}{15.10.}{%
Hier muss jetzt irgendetwas hinkommen, was, weiss ich auch nicht genau}
\uput*{1.2cm}[-90](A0){17.10.}%
\endpspicture

\bye