Re: Microtonal accidentals

[Hans Aberg]

On 3 Nov 2013, at 11:49, Joseph Rushton Wakeling <address@hidden> wrote:

> On 03/11/13 11:42, Joseph Rushton Wakeling wrote:
>> For Lilypond in particular, the problem of supporting microtonal notation is
>> less about symbols per se and more about the underlying representation of 
>> pitch,
>> and how that relates both to accidentals and transposition.
> 
> Specifically in relation to the Helmholtz-Ellis notation -- some of those 
> accidentals would play very badly with existing Lilypond transposition rules.
> 
> The double-sharp-up-arrow (i.e. approx +5/4 tone) and double-flat-down-arrow 
> (approx. -5/4 tone) would clash with the hardcoded transposition rule that 
> sees any accidental pitch alteration greater than 1 tone rewritten to a new 
> staff pitch with smaller alteration.

I think that LilyPond does what is correct, namely does not apply any E12 
enharmonic equivalences unless called for by some special functions. The 
problem is that the computations are tied to some explicit rational intervals. 
It seems that the stuff that Graham Breed wrote might work. I am looking at 
E53, which is how I came across the links, trying to decide which accidentals 
to use.