Re: Lilypond's internal pitch representation and microtonal notation

[Joseph Wakeling]

On 09/20/2010 12:23 PM, Hans Aberg wrote:
>> I saw the post but was not sure quite how to interpret it.
> 
> I expected someone to ask for details. In the past, I discussed part of
> it with Graham Breed, who did some LilyPond microtonal implementation,
> but perhaps he is not working on it anymore.

I get the feeling activity is rather focused right now on getting 2.14
released ... :-)

I also discussed microtonal stuff with Graham Breed a while back, but we
weren't really able to bring anything to a satisfactory conclusion.

> If you want, I can explain it - the algorithm itself is very simple.
> Writing up it in math style will probably not make it more accessible.

It would make it clearer to me, surely.  What I'd like to see is for it
to be written up in a structured way along the lines of (i) this is the
problem that needs solving, (ii) this is the approach the algorithm
takes to solve the problem, (iii) this is the algorithm.

>> I did wonder if the fact it was Haskell code was part of the reason for
>> the lack of response.  I have a lot of admiration for Haskell but I can
>> see there being problems extending Lilypond with yet another language.
> 
> It should not be difficult to translate into Scheme - no specific
> Haskell features are used, only better syntax and type system to help
> structuring the code. It is just a page.
> 
> The difficulty is to figure out to put it into LilyPond.

Indeed, it sounds like a pretty fundamental
major-version-number-changing kind of modification.

As a related issue, have you considered how (different kinds of)
transposition would be handled in your pitch scheme?

Best wishes,

    -- Joe