Re: Rotating/grouping grobs for microtonal accidentals

[Torsten Anders]

Dear Mats

thank you for your kind reply and sorry for my late response. The  
example you provided does indeed work nicely for monotonic voices.  
However, it appears it does not work for chords

%% !! causes lilypond parsing error!
\version "2.10.0"
\relative c'{
  c d e
  < \once \override Accidental #'stencil = #ly:text-interface::print
    \once \override Accidental #'text = \markup{\rotate #180  
\musicglyph #"scripts.lvarcomma"}
    dis
    \once \override Accidental #'stencil = #ly:text-interface::print
    \once \override Accidental #'text = \markup{\rotate #180  
\musicglyph #"scripts.rvarcomma"}
    fis
    \once \override Accidental #'stencil = #ly:text-interface::print
    \once \override Accidental #'text = \markup{\rotate #90  
\musicglyph #"scripts.lvarcomma"}
    ais >
  e d c1 }

> This solution will not automatically recognize what glyph to use  
> depending on
> the pitch of the note. Rather you will have to manually specify  
> what markup to
> use for each accidental.

Such a restriction would be totally fine for me -- in the end I am  
generating the *.ly file automatically by a program.

> A more advanced solution would be to write a few lines of Scheme  
> code that
> automatically gives you the proper accidental based on the note pitch.

This is what I tried in the first place by starting with the maqam  
example shown in the list of new features at

  http://lilypond.org/doc/v2.11/Documentation/topdocs/NEWS.html.

I do know Scheme, but I don't know the internals of Lilypond which I  
would like to change :) Attached is a *.ly file which shows a working  
example I did for a microtonal notation in 22-tone equal temperament  
(using common Feta-font accidentals, just to have a working example).

Now, all I want to do is replace the accidental signs either by signs  
from another font or by transformations of Feta-font characters  
(e.g., using text markup, as you suggested). More specifically, I  
want to change the following section of the attached example which  
changes the glyph-name-alist of the Accidental context (please see  
example excerpt below). Unfortunately, I don't know whether/how I can  
use some text markup in the etTwentytwoGlyphs specification.


% ---------- example start

% cut out declarations, see attached files
% [...]

%% set pitch names.
pitchnames = \etTwentytwoPitchNames
#(ly:parser-set-note-names parser etTwentytwoPitchNames)

etTwentytwoGlyphs = #'((1 . "accidentals.doublesharp")
       (1/2 . "accidentals.sharp")
       (1/3 . "accidentals.sharp.slashslashslash.stem")
       (1/6 . "accidentals.sharp.slashslash.stem")
       (0 . "accidentals.natural")
       (-1/3 . "accidentals.flat.slash")
       (-1/6 . "accidentals.flat.slashslash")
       (-1/2 . "accidentals.flat")
       (-1 . "accidentals.flatflat")
       )

{

\override Accidental #'glyph-name-alist =  \etTwentytwoGlyphs

\override Staff.KeySignature #'glyph-name-alist = \etTwentytwoGlyphs

% actual score follows here

}

% ------------ example end



Any help is much appreciated!

Best
Torsten


PS: Please note also that such an approach (which allows for  
arbitrary text markup as accidentals) could likely provide Lilypond  
support for arbitrary microtonal notations. As demonstrated by the  
maqam example, Lilypond users can define arbitrary fractions of a  
whole tone step and associate them with custom Lilypond note names  
and custom accidental symbols. Of course, not all microtonal music  
can be expressed by fractions of a whole tone step, but in the end  
these fractions can be irrelevant for the notation. We simply have a  
mapping of user-defined note names to pitches with user-defined  
accidentals.  For example, the huge set of accidentals in Sagittal  
notation could be supported this way, if we can use their true type  
font or postscript font via pango. I am mentioning this to show the  
potential I see in this approach :)

  http://users.bigpond.net.au/d.keenan/sagittal/

ET22-Lilytest.ly
Description: Binary data

On Mar 31, 2008, at 10:45 AM, Mats Bengtsson wrote:

> As far as I understand, the answer to both of your questions is  
> that you
> have to replace the function that normally is done to typeset the  
> accidentals
> with your own function. This is not necessarily so difficult as it  
> first may seem.
> The simplest solution is to use the standard function used to  
> typeset any "text"
> and specify the glyph to be printed as a markup, for example:
>
> \version "2.10.0"
> \relative c'{
> \once \override Accidental #'stencil = #ly:text-interface::print
> \once \override Accidental #'text = \markup{\rotate #180  
> \musicglyph #"scripts.lvarcomma"}
> cis d e f g f e d c1 }
>
> This solution will not automatically recognize what glyph to use  
> depending on
> the pitch of the note. Rather you will have to manually specify  
> what markup to
> use for each accidental. Of course, you can still use the standard  
> mechanism
> for the accidentals where the Feta font has a suitable glyph and  
> only use the
> workaround for the rest. Don't forget to define macros for the  
> different settings
> to save some typing.
> A more advanced solution would be to write a few lines of Scheme  
> code that
> automatically gives you the proper accidental based on the note pitch.
>
>    /Mats
>
> Torsten Anders wrote:
> > On Mar 28, 2008, at 8:58 PM, Torsten Anders wrote:
> > > I would like to define a microtonal notation with alteration  
> > > fractions (cf. http://lilypond.org/doc/v2.11/Documentation/ 
> > > topdocs/NEWS.html) -- thanks for providing this feature!  
> > > Everything works great.
> > >
> > > My only problem is the creation of suitable accidentals. I need  
> > > four additional signs: a comma up (/), a comma down (\), and a  
> > > combination of these signs with the standard accidentals (#\ and  
> > > b/). I figure I could use something like "scripts.lvarcomma" for  
> > > a comma up. For a comma down, however, I need to rotate this sign  
> > > or "scripts.rvarcomma". Moreover, I would like to group my commas  
> > > with the common accidentals. How can I rotate and group feta font  
> > > symbols which I want to add to the list of accidentals.
> > >
> > > % code does not work, should only clarify problem
> > > myGlyphs = #'((1 . "accidentals.doublesharp")
> > >     [...]
> > >        (1/6 . "scripts.rvarcomma")
> > >        (0 . "accidentals.natural")
> > >     ;; how can I rotate a symbol?
> > >        (1/6 . (rotate "scripts.lvarcomma"))
> > >     [...]
> > >        )
> >
> > Alternatively, is it perhaps possible to use another font (e.g.,  
> > TrueType, or some PostScript font) for the accidentals?
> >
> > Thank you!
> >
> > Best
> > Torsten

--
Torsten Anders
Interdisciplinary Centre for Computer Music Research
University of Plymouth
Office: +44-1752-233667
Private: +44-1752-558917
http://strasheela.sourceforge.net
http://www.torsten-anders.de