t-lilypond.mkiv

%D \module
%D   [     file=t-lilypond,
%D      version=2011.08.22,
%D        title=\CONTEXT\ User Module,
%D     subtitle=Lilypond,
%D       author=Aditya Mahajan and Henning Hraban Ramm,
%D         date=\currentdate,
%D    copyright=Aditya Mahajan and Henning Hraban Ramm,
%D        email=adityam <at> umich <dot> edu and hraban@fiee.net,
%D      license=Simplified BSD License]
\writestatus{loading}{Lilypond (ver:2011.08.22)}

\startmodule    [lilypond]
\usemodule      [filter]

\unprotectmodulecatcodes

\def\lilypond::preamble{lilypond::preamble}

\defineexternalfilter
    [lilypond]
    [\c!continue=\v!yes,
     \c!setups=lilypond::setups,
     \c!output=\externalfilterbasefile-systems.tex, 
     \c!buffer\c!before=\lilypond::preamble,
     \c!filter=\lilypond::filter,
     \c!alternative=\v!float]

\def\setuplilypond
    {\setupexternalfilter[lilypond]}

% Based on an idea of David Wooten
\definefloat
  [lilypondfloat]
  [lilypondfloats]
  [figure]

\setupfloat
  [lilypondfloat]
  [\c!frame=\v!off,
   \c!location=\v!right,
   \c!default={\v!nonumber,\v!here,\v!always}]

\def\lilypond::readPDFfile::float#1%
    {\placelilypondfloat{}{\externalfigure[#1]}}

\def\lilypond::readPDFfile::display#1%
    {\rightaligned{\externalfigure[#1]}}

\def\lilypond::readPDFfile::inline#1%
    {\externalfigure[#1][\c!location=\v!lohi]}

\def\lilypond::filter
    {lilypond 
      -dbackend=eps 
      -dinclude-eps-fonts 
      -dno-gs-load-fonts 
      -dno-strip-output-dir
      \iftraceexternalfilters \else
        -ddelete-intermediate-files
      \fi
      % DO NOT add -o option!
      % Otherwise the name of graphic in \includegraphics
      % is relative to the output directory.
    }


% When lilypond processes a file, it saves the typeset music scores in a 
% pdf file and generates a latex file to include these pdf images. Rather 
% than trying to reproduce the logic used in lilypond, I simply include the 
% resulting latex file. In order to do so, we need to tell define \includegraphics
% at the ConTeXt end.

\startsetups lilypond::setups
  \def\includegraphics{\getvalue{lilypond::readPDFfile::\externalfilterparameter\c!alternative}}
  \writestatus{lilypond}{alternative: \externalfilterparameter\c!alternative}
  \let\linebreak       \donothing
\stopsetups

\startluacode
local template = [[
%% \string\include "lilypond-book-preamble.ly"

\string\version "2.14.0"
#(define version-seen #t)

\string\layout {
  \string\context { \string\RemoveEmptyStaffContext } 
  \string\context { \string\Score \string\override VerticalAxisGroup #'remove-first = ##t }

  \string\context { \string\Score timing = ##f }
  \string\context { \string\Score \string\remove "Time_signature_engraver" }

  \string\context { \string\Score \string\remove "Bar_number_engraver" }
}

\string\paper {
  #(define dump-extents #t)
  line-width    = %s
  vsize         = %s 
  indent        = 0.0

  printpagenumber  = ##f
  oddFooterMarkup  = ##f
  oddHeaderMarkup  = ##f
  bookTitleMarkup  = ##f
  scoreTitleMarkup = ##f

  ragged-right     = %s

  ragged-last-bottom = ##t
  ragged-bottom      = ##t

  between-system-padding = #0
  between-system-space   = 54\string\pt
}

]]

local raggedright = {
  ["float"]   = "##f",
  ["display"] = "##f",
  ["inline"]  = "##t",
}

local function initialize(name, properties)
  properties.raggedright = raggedright[properties.alternative]
  properties.hsize = number.topoints(string.todimen(properties.hsize), "%0.3f\\pt") or "6\\in"
  properties.vsize = number.topoints(string.todimen(properties.vsize), "%0.3f\\pt") or "6\\in"
  buffers.assign(name, string.format(template, properties.hsize, properties.vsize, 
                 properties.raggedright))
end

commands.lilypondinitialize = initialize
\stopluacode

% Ugly hack

\def\stoplilypond
    {\setlocalhsize
     \ctxcommand{lilypondinitialize("\lilypond::preamble", 
                 { hsize = "\the\localhsize", 
                   vsize = "\the\vsize",
                   alternative = "\externalfilterparameter\c!alternative",
                 })}
     \externalfilter::process_filter}

\protectmodulecatcodes

\stopmodule