%D   [      file=s-present-banner,
%D        version=2016.04.30, % around
%D          title=\CONTEXT\ Style File,
%D       subtitle=Presentation Environment Banner,
%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 This style was made for the Bacho\TeX\ 2016 conference. The banner below
%D the text advances through the title.

\startmodule[present-banner]

\definecolor[maincolor] [b=.65]
\definecolor[othercolor][s=.35]

\startluacode
    function mp.Banner(s,mode)
     -- local r = tex.count.realpageno
        local r = tex.count.realpageno - 1
        local n = #s
        local i = mode and 1 or 0
        local t = string.gsub(s,".",function(s)
            if s == " " or i > n then
                return s
            elseif i == r then
                i = i + 1
                if mode then
                    return "\\color[othercolor]{" .. s .. "}"
                else
                    return "\\maincolor " .. s
                end
            else
                i = i + 1
                return s
            end
        end)
        mp.quoted(t)
    end
\stopluacode

\startuseMPgraphic{page}
    StartPage ;
        fill Page withcolor \MPcolor{maincolor} ;
        draw anchored(image (
          % draw textext.top (lua.mp.Banner("\documentvariable{title}",true))
            draw textext.top (lua.mp.Banner("\documentvariable{title}",false))
                xsized (.9PaperWidth)
                withcolor white;
        ), center bottomboundary Page);
      % fill Field[Text][Text] enlarged 10pt withcolor (\MPcolor{maincolor})/1.5 ;
        fill Field[Text][Text] enlarged 10pt withcolor .1white ;
    StopPage ;
\stopuseMPgraphic

\setupbackgrounds
  [page]
  [background=page]

\defineoverlay
  [page]
  [\useMPgraphic{page}]

\setupbodyfont
  [lucidaot,10pt]

\setuppapersize
  [S6]

\setuplayout
  [backspace=30pt,
   width=middle,
   height=middle,
   topspace=30pt,
   bottomspace=100pt,
   header=0pt,
   footer=0pt,
   margin=0pt]

\setupcolors
  [textcolor=white]

\setupwhitespace
  [big]

\setuphead
  [chapter]
  [style=\bfd,
   after={\blank[big]}]

\setuphead
  [section]
  [style=\bfa,
   before=\blank,
   after={\blank[medium]}]

\definehighlight[nb][style=bold]

\setupitemgroup[itemize][before=,after=]
\setupitemgroup[itemize][packed]

\setupdocument
  [title=Title,
   subtitle=Subtitle,
   location=\currentdate]

\startsetups document:start

    \startstandardmakeup

        \raggedcenter

        \dontleavehmode\scale[width=1.00\textwidth]{\documentvariable{title}}    \vfil
        \dontleavehmode\scale[width=0.75\textwidth]{\documentvariable{subtitle}} \vfil
        \dontleavehmode\scale[width=0.45\textwidth]{\documentvariable{location}} \vfil

    \stopstandardmakeup

\stopsetups

\stopmodule

\continueifinputfile{s-present-banner.mkiv}

\usemodule[present-common]

\inputpresentationfile{bachotex/2016/bachotex-2016-opentype.tex}