Re: Acciaccaturas and slashed stems

[Thomas Morley]

2013/9/20 David Kastrup <address@hidden>:
>
> Gilberto Agostinho <address@hidden> writes:
>
>> Well David, thanks for your answers and opinions. Even though I really
>> respect your views (and you certainly know infinitely more about
>> LilyPond and programming than I do), I still think I am right on this
>> one. I personally see the lack of slashes on beamed grace notes + the
>> lack of automatic beaming for grouped grace notes as major drawbacks
>> with LilyPond.
>
> I've entered an issue in the tracker
> <URL:http://code.google.com/p/lilypond/issues/detail?id=3566> and it's
> probably mostly grind work to implement it in a way that can easily be
> switched off when required.
>
> That does not mean that anybody will get excited enough about it to
> actually implement it: merely that the discussion and a sketch at a
> solution have been registered in a way making it easier to find at a
> later point of time.
>
> --
> David Kastrup

Hi Gilberto,

I coded some thoughts about automatically beaming grace notes. Comments in code.
It's not an engraver, as supposed by David, (this should be done in
C++ like the others), though, I hope it's of some use for you.


\version "2.17.26"
%% Works with "2.16.2", too.
%% Though, there are some issues of vertical spacing with fingerings, etc
%% in 'GraceMusic.
%% 'add-stem-support might help, not tested, though.

beamMe =
#(define-music-function (parser location music)(ly:music?)
;; TODO: test it with real life examples.
 "A quite simple defined function to beam @var{music} by adding @code{[} and
  @code{]} to @code{articulations} of the first and last element of its
  code{elements}-list.
 "
 (let* ((elts (ly:music-property music 'elements))
        (first (first elts))
        (last (last elts)))

   (for-each
     (lambda (m)
       (let ((art (ly:music-property m 'articulations)))
       (cond ((eq? first m)
              (ly:music-set-property! m 'articulations
                (append art (list #{ [ #}))))
             ((eq? last m)
              (ly:music-set-property! m 'articulations
                (append art (list #{ ] #}))))
             (else #f))))
     elts)
   music))


%% Modified c/p from music-functions.scm
#(defmacro-public def-grace-function (start stop . docstring)
  "Helper macro for defining grace music.
   Containing an optional @var{beamed?}, which determines whether the
   @var{music} should be beamed or not, using the (very simple defined)
   music-function @code{beamMe}.
   The default for @var{beamed?} is set @code{#f}. Change it to @code{#t}?
  "
  `(define-music-function (parser location beamed? music)
           ((boolean? #f) ly:music?)
     ,@docstring
     (make-music 'GraceMusic
                 'origin location
                 'element (make-music
                            'SequentialMusic
                            'elements (list (ly:music-deep-copy ,start)
                                            (if beamed?
                                                #{ \beamMe $music #}
                                                music)
                                            (ly:music-deep-copy ,stop))))))

%% Unmodified c/p from music-functions-init.ly
%% Needs to be here, otherwise the modified def-grace-function wouldn't apply
acciaccatura =
#(def-grace-function startAcciaccaturaMusic stopAcciaccaturaMusic
   (_i "Create an acciaccatura from the following music expression"))

appoggiatura =
#(def-grace-function startAppoggiaturaMusic stopAppoggiaturaMusic
   (_i "Create an appoggiatura from @var{music}"))

grace =
#(def-grace-function startGraceMusic stopGraceMusic
   (_i "Insert @var{music} as grace notes."))

%%%%%%%%%%%%%%%%%%%%%%%%%%%
% EXAMPLE
%%%%%%%%%%%%%%%%%%%%%%%%%%%

testGraces = { c16 d e f e32 <d-1\3 f-2\4>--^"foo" }
mainMusic = { c8 c }

\relative c'' {
  \time 2/8

  \mark "default acciaccatura"
  \acciaccatura \testGraces \mainMusic
  \break

  \mark "beamed acciaccatura, no slash, though"
  \acciaccatura ##t \testGraces \mainMusic
  \break

  \mark "default appoggiatura"
  \appoggiatura \testGraces \mainMusic
  \break

  \mark "beamed appoggiatura"
  \appoggiatura ##t \testGraces \mainMusic
  \break

  \mark "default grace"
  \grace \testGraces \mainMusic
  \break

  \mark "beamed grace"
  \grace ##t \testGraces \mainMusic
}

%% Some settings for \layout, \paper, \header

\layout {
  \context {
    \Score
    \override RehearsalMark #'self-alignment-X = #LEFT
    \override RehearsalMark #'padding = #4
    \override RehearsalMark #'break-align-symbols = #'(left-edge)
    \override BarNumber #'transparent = ##t
    \override TimeSignature #'stencil = ##f
  }
}

\paper {
  indent = 0
  line-width = 100
  markup-system-spacing #'padding = #8
}

\header {
  title = "Grace with and without Beam"
  subtitle =
  \markup \normal-text {
        #(format "Used LilyPond-version: ~a" (lilypond-version))
  }
  subsubtitle =
  \markup \medium \override #'(line-width . 60) \justify {
    The commands \typewriter "\\acciaccatura", \typewriter "\\appoggiatura" and
    \typewriter "\\grace" are working as before.
    If you want a beam from the first to the last note add \typewriter  "##t"
    after them. \hspace #30
    Example: \typewriter "\\acciaccatura ##t { ... }"
  }
}


My tries to add slashes are not convincing so far, I'll keep thinking
about them. ;)

HTH,
  Harm