Re: Doc: Some miscellaneous suggestions from Peter Toye (issue 579280043 by address@hidden)

[michael . kaeppler]

On 2020/02/09 16:15:53, thomasmorley651 wrote:
> On 2020/02/09 15:32:14, http://lilypond_ptoye.com wrote:
> 
> > Surely "standard scale pitch or previously altered pitch". In D
major: "cis c
> > cis" the first note is an alteration but not an accidental, the
second is an
> > accidental but not an alteration, the third is both. Now I'm really
splitting
> > hairs.
> 
> I read this as "In D major the note c _is_ an accidental". 
> Or did you mean _has_ an accidental?
> 
> > I'm beginning to think that this is all getting too theologial. I'm
a
> practising
> > musician, not a theorist, and I raised the point as I'd never heard
of
> > 'alteration' used in this rather technical sense. If people are
happy with the
> > distinction let's just keep it and I withdraw my suggestion.
> 
> Wait. If we try to improve the docs we need to care about best
wordings, so that
> people speaking different language and with different musical
education
> understand what we want to express.

+1

> 
> Furthermore we need to explain how we do things in LilyPond.
> Look at:
> mus = { \key d \major cis'4 }
> #(display-scheme-music (car (music-pitches mus)))
> #(display-scheme-music (ly:pitch-alteration (car (music-pitches
mus))))
> =>
> (ly:make-pitch 0 0 1/2)
> 1/2
> 
> First how the cis is seen in LilyPond, second the alteration.
(ofcourse no
> Accidental is printed in pdf)
> Do the same with note c and you see no alteration, i.e. 0 (ofcourse an
> Accidental is printed)
> Do similar with c and cis (and you see the alteration for cis again
and an
> accidental for cis is printed)

However, I think that the description of LilyPond's internal pitch data
structure
is not helpful for this (pretty introductory) part of the docs.
The longer I think about it, the more I'm unsure if the term
"alteration" makes
sense for a basic understanding how pitches are entered in LilyPond.
If I think about a, lets say D major scale, I would not say that the
pitch 'fis' is an 'altered' note, though it is stored that way in the
data structure. 'Alteration' for me always refers to some 'unaltered'
form. 
Our pitch naming system with a 'nucleus' (e.g. 'f') and some suffices
(e.g. '-is') OTOH supports the conclusion, that a pitch consists of 
some base, diatonic pitch and possibles alterations.
It is also conclusive, though, that LilyPond 
uses the C major scale as the base for its pitch structure.


> 
> This is absolutely inline with my thinking.
> Though, c itself in D major can't be called an accidental.
> In my book an Accidental is always the printed ♯-sign or ♭-sign or
natural or
> double-sharp/flat, nothing else, never the note itself.

+1

> 
> Furthermore in german we have the distinction between "Vorzeichen" and
> "Versetzungszeichen", in lilypond that would be the accidental-grobs
from
> KeySignature and the additional "on the fly"  Accidentals in music.

Can you cite sources for this? Being also a practising german musician
I've never used the term "Versetzungszeichen" and I thought it to
be synonymous with "Vorzeichen". What I know and (rarely) use is
the term "Generalvorzeichen". These would be the KeySignature
accidentals. 


https://codereview.appspot.com/579280043/