Re: Setting up classical guitar fingerings

[Luca Fascione]

Thanks Valentin, this is useful.

Sounds like I'll be back with questions :-)

L

On Sat, Mar 5, 2022 at 5:46 PM Valentin Petzel <valentin@petzel.at> wrote:

> Hello Luca,
>
> the design of Lilypond inherently implies that there is no clear border
> between users and developers. Lilypond has an user interface, which is
> covered
> more or less in the docs, an extended interface in scheme, which is not
> documented that extensively, and the C++ code that works behind this,
> which
> barely documented. This means that in the Lilypond-verse it is useful to
> speak
> Lilypond, Scheme, C++ (and maybe Python), with basic users sitting at the
> Lilypond end and developers sitting at the C++ side, with the scheme stuff
> hanging in between.
>
> This means that you as a user can turn into a developer of some sort and
> write
> code into you Lilypond score that drastically changes how Lilypond does
> things
> (which is kind of cool). But if you are trying to do this you will often
> find
> yourself in the situation that you do not know how certain things are
> handled
> and the docs offer very little support.
>
> Thus I find it easier to look directly into the code. Lilypond has three
> directories of relevant code in it’s source directory:
>
> → Ly: Which contains code in Lilypond-Language, mostly setting up the
> defaults
> and music functions and such
> → scm: Which contains code in Scheme and contains a decent bit of
> Lilypond’s
> functionality, at least that part which does not matter that much
> performance-
> wise
> → lily: Which contains the c++-Code, which is the major part of the core
> functionality.
>
> If I’m looking for things I usually grep for these things in these
> directories. Eventually you’ll have a good idea where what is sitting. For
> example a scheme function like  ly:somethingA::somethingB is usually a
> callback to the c++ class somethingA, method somethingB.
>
> In scm you also have the definitions of the default grobs, so if you want
> to
> know what exact properties a grob has, you can look in define-grobs.scm.
> And
> similar stuff.
>
> And if you encounter something you really do not understand, ask the list.
> We’ve got some really marvellous people here who appear to know about
> everything you might want to know about Lilypond.
>
> Cheers,
> Valentin
>
> Am Samstag, 5. März 2022, 17:05:22 CET schrieb Luca Fascione:
> > I took a "brief" detour where I went and learned a bit about scheme
> > ==== Interlude
> > FWIW, I don't recall seeing this reference in your resources about
> learning
> > Scheme, so I'll leave a comment here:
> >
> > Paul Wilson (professor at UTexas, Austin) wrote some notes on Scheme
> approx
> > in 1996,
> > which I thought were extremely well conceived and clear. Certainly more
> to
> > the point that sicp
> > (which is a very interesting approach if you're learning Lisp and sw
> > engineering at the same time,
> > but I found did not make good use of my pre-acquired understanding of the
> > field, and just slowed me down).
> > I found the book very easy to follow and I loved that he teaches Scheme
> by
> > showing a series of gradually
> > more accurate implementations of scheme, partially in scheme. Also it
> > teaches Scheme in a way that is
> > very compatible with other programming languages, that makes it really
> easy
> > to keep it straight in one's head
> > what is new information or different vs what is just the same.
> > Unfortunately the several available copies online were never completed,
> so
> > there are several little bugs,
> > missing cross-references and other polish-grade features missing. But I
> > thought the juice of the book is certainly excellent.
> >
> > It seems Prof Wilson has since retired, and various threads on the
> internet
> > indicate folks are unable to reach him.
> > He seems to have done work in the 90's about garbage collection in
> > languages.
> > ====
> >
> > Now that I can follow Scheme source with a certain level of confidence, I
> > went back to work on the fingering task,
> > and re-read Valentin's code. And thanks again kind sir.
> >
> > I was thinking again about the idea of instead of pushing the fingering
> > "down" (say we're doing \stemsUp) because the beams are too low,
> > to push the beams "up" to leave space for the fingering. And I played
> for a
> > second with Stem.details.beamed-lengths
> > (using an override in the .ly file, inbetween the notes) which seems to
> > achieve what we need.
> > So in order to automate that, I'd like to understand better the execution
> > of before-line-break and after-line-break callbacks.
> > I'm thinking that I could set up the fingering position in
> > Fingering.before-line-break and alter the stem length
> > (details.beamed-lengths, being my current thinking) in
> > Stem.before-line-break.
> >
> > Really the question is a meta-question: I can certainly hack at this and
> > see what happens, but also how I do help myself learn this better:
> > where is the code that handles this stuff and how do I trace the sequence
> > of events around this stuff?
> >
> > I'm looking for a couple one-liner breadcrumbs such as "this section of
> the
> > docs" (which I tried to read without much success),
> > "grep <this> and <that> in the source", it's all in "scm/<couple
> > filenames>". Vague pointers like that are hopefully all I'll need.
> >
> > Many thanks,
> > Luca
> >
> > On Mon, Feb 21, 2022 at 6:49 PM Luca Fascione <l.fascione@gmail.com>
> wrote:
> > > Yes exactly, because of how our finger to note relation works, the
> > > enhancement in readability with the indication right at the head is
> > > enormous.
> > >
> > > L
> > >
> > > On Mon, 21 Feb 2022, 18:16 Valentin Petzel, <valentin@petzel.at>
> wrote:
> > >> Sure. I suppose for a guitar person having stacked fingerings on top
> > >> would be
> > >> rather confusing, as there is no monotonic relating between finger and
> > >> pitch.
> > >> As such I suppose guitar people would want to use fingerings with
> left or
> > >> right
> > >> orientations in chords anyway.
> > >>
> > >> Cheers,
> > >> Valentin
> > >>
> > >> Am Montag, 21. Februar 2022, 17:47:58 CET schrieb Luca Fascione:
> > >> > I suspect we might be saying the same thing, Valentin?
> > >> >
> > >> > I was saying infix can be a bit awkward if you want 'pianist' chord
> > >> > fingering (just a stack of numbers above or below), and that your
> > >>
> > >> original
> > >>
> > >> > <c d g>-1-2-3 reads quite nicely (as in: it's easy to see in your
> head
> > >>
> > >> what
> > >>
> > >> > you will get in the engraving just by looking at the source). So a
> > >>
> > >> keyboard
> > >>
> > >> > person wouldn't want to use infix, I don't think
> > >> >
> > >> > Whereas a guitar person might find it more attractive to use <c-1
> d-2
> > >>
> > >> g-3>
> > >>
> > >> > because it's easier to keep it straight in your head what fingers
> you
> > >>
> > >> use
> > >>
> > >> > on what note that way
> > >> >
> > >> > L
> > >> >
> > >> > On Mon, Feb 21, 2022 at 5:42 PM Valentin Petzel <valentin@petzel.at
> >
> > >>
> > >> wrote:
> > >> > > No, not nescessarily. If we want all Fingerings on top or below
> there
> > >>
> > >> is
> > >>
> > >> > > no real benefit of doing the chord thing. In fact doing that
> leads to
> > >>
> > >> the
> > >>
> > >> > > exact same issue of the fingering for d being next to the other
> ones.
> > >> > >
> > >> > > Cheers,
> > >> > > Valentin
> > >> > >
> > >> > > 21.02.2022 12:38:40 Luca Fascione <l.fascione@gmail.com>:
> > >> > >
> > >> > > But wouldn't you finger that as <c-1 d-2 g-3>? (Didn't check the
> > >>
> > >> number,
> > >>
> > >> > > I'm just meaning going infix vs postfix)
> > >> > >
> > >> > > I can see that this idea of mine does have issues for fingering
> your
> > >>
> > >> way
> > >>
> > >> > > around (which seems to me it's more of a fingering atop thing,
> like
> > >>
> > >> you
> > >>
> > >> > > would have in a keyboard score)
> > >> > >
> > >> > > L
> > >> > >
> > >> > > On Mon, 21 Feb 2022, 12:32 Valentin Petzel, <valentin@petzel.at>
> > >>
> > >> wrote:
> > >> > >> Hello Luca,
> > >> > >>
> > >> > >> changing the X-parent to the NoteHead would mean that we are
> > >>
> > >> aligning the
> > >>
> > >> > >> Fingering horizontally wrt. the NoteHead instead of the whole
> > >>
> > >> NoteColumn.
> > >>
> > >> > >> This
> > >> > >> would then mean that if for example due to some chord some note
> > >>
> > >> heads are
> > >>
> > >> > >> on
> > >> > >> the other side of the Stem the alignment of something like <c d
> > >>
> > >> g>-1-2-3
> > >>
> > >> > >> would
> > >> > >> change (disregarding that it wouldn’t even be clear what note
> head
> > >> > >> to
> > >> > >> use).
> > >> > >>
> > >> > >> Cheers,
> > >> > >> Valentin
> > >> > >>
> > >> > >> Am Montag, 21. Februar 2022, 09:19:30 CET schrieb Luca Fascione:
> > >> > >> > Hi Thomas,
> > >> > >> > thanks for your comment, this helps me refine my understanding
> of
> > >> > >>
> > >> > >> what's
> > >> > >>
> > >> > >> > going on.
> > >> > >> >
> > >> > >> > At the same time, while I do see that for other articulations
> > >>
> > >> (fermata,
> > >>
> > >> > >> > appoggiato) this parenting scheme works very well,
> > >> > >> > I remain wondering whether for the style of layout of the
> > >> > >> > fingering
> > >> > >> > indications that I am after, the appropriate thing to do could
> be
> > >>
> > >> to
> > >>
> > >> > >> change
> > >> > >>
> > >> > >> > the parenting altogether.
> > >> > >> >
> > >> > >> > If we look at chord for a second, I see the <one-note-chord>
> thing
> > >>
> > >> as a
> > >>
> > >> > >> > trick because to me even for proper chords the whole
> > >>
> > >> FingeringColumn
> > >>
> > >> > >> idea
> > >> > >>
> > >> > >> > is also a weird concept: imagine you're in say C major, and
> you're
> > >> > >>
> > >> > >> laying
> > >> > >>
> > >> > >> > out fingering on the left of a chord like Fm <f aes c'>: I'm
> very
> > >> > >>
> > >> > >> unclear
> > >> > >>
> > >> > >> > whether the most readable solution is to have the fingerings
> > >>
> > >> stacked
> > >>
> > >> > >> one
> > >> > >>
> > >> > >> > atop each other in a column (thereby more distant from f and c
> > >>
> > >> because
> > >>
> > >> > >> of
> > >> > >>
> > >> > >> > the intervening flat on the aes) or if instead the fingerings
> on f
> > >>
> > >> and
> > >>
> > >> > >> c
> > >> > >>
> > >> > >> > should be set tighter to their corresponding note heads and
> just
> > >>
> > >> the
> > >>
> > >> > >> aes
> > >> > >>
> > >> > >> > fingering be displaced left horizontally, to allow for the
> flat. I
> > >> > >>
> > >> > >> would
> > >> > >>
> > >> > >> > like to experiment with various possibilities there, visually.
> I
> > >> > >>
> > >> > >> suppose
> > >> > >>
> > >> > >> > you could still displace horizontally inside the column, and
> then
> > >>
> > >> push
> > >>
> > >> > >> it
> > >> > >>
> > >> > >> > all inwards closer to the chord even if the bboxes will
> overlap a
> > >> > >>
> > >> > >> bit... I
> > >> > >>
> > >> > >> > anticipate issues such as making sure the fingering for c'
> doesn't
> > >> > >> > interfer with the ascender on the flat glyph, also.
> > >> > >> >
> > >> > >> > Which brings me to a question: what consequence would it have
> to
> > >> > >>
> > >> > >> replace
> > >> > >>
> > >> > >> > the X-parent and Y-parent of the fingering to be the NoteHead
> > >>
> > >> instead?
> > >>
> > >> > >> > (I guess there will be a need to deal with the accidentals at a
> > >> > >>
> > >> > >> minimum)
> > >> > >>
> > >> > >> > And also: how would I go at discovering these consequences
> without
> > >> > >>
> > >> > >> using
> > >> > >>
> > >> > >> > too much of you guys' time?
> > >> > >> >
> > >> > >> > Thanks again,
> > >> > >> > Luca
> > >> > >> >
> > >> > >> > On Mon, Feb 21, 2022 at 1:22 AM Thomas Morley
> > >> > >> > <thomasmorley65@gmail.com>
> > >> > >> >
> > >> > >> > wrote:
> > >> > >> > > Am So., 20. Feb. 2022 um 22:41 Uhr schrieb Luca Fascione <
> > >> > >> > >
> > >> > >> > > l.fascione@gmail.com>:
> > >> > >> > > >  a) I'm looking for a way to get the fingerings where I
> want
> > >>
> > >> them
> > >>
> > >> > >> > > >  without
> > >> > >> > > >
> > >> > >> > > > using one-note-chord tricks
> > >> > >> > >
> > >> > >> > > Well, for Fingerings not in chord, like b-1 or <b dis'>-2-1
> > >>
> > >> X-parent
> > >>
> > >> > >> > > is NoteColumn _not_ NoteHead, Y-parent  is VerticalAxisGroup.
> > >> > >> > > There is no direct way from NoteHead to Fingering and vice
> > >> > >> > > versa.
> > >> > >> > >
> > >> > >> > > Thus putting Fingering in-chord is unavoidable, imho, even
> for
> > >>
> > >> single
> > >>
> > >> > >> > > notes.
> > >> > >> > > It is _not_ a trick, but a requirement.
> > >> > >> > >
> > >> > >> > > Furthermore, you say you set music for classical guitar, then
> > >>
> > >> chords
> > >>
> > >> > >> > > will happen anyway, although not in your example.
> > >> > >> > > Please note, as soon as more than one in-chord Fingering is
> > >>
> > >> present a
> > >>
> > >> > >> > > FingeringColumn is created. Which will make things even more
> > >> > >> > > complicated.
> > >> > >> > > See
> > >> > >> > > https://gitlab.com/lilypond/lilypond/-/issues/6125
> > >> > >> > > https://gitlab.com/lilypond/lilypond/-/merge_requests/732
> > >> > >> > >
> > >> > >> > > Sorry to be of not more help,
> > >> > >> > >
> > >> > >> > >   Harm
>
>