Re: MIDI remapping

[Carl Sorensen]

On 1/22/11 5:09 AM, "Bernard Hurley" <address@hidden> wrote:

> On Sat, Jan 22, 2011 at 10:34:29AM +0000, c.m.bryan wrote:
>> Hi, I have an interesting question.  I know lilypond is not really
>> meant for playback.  HOWEVER :)
>> 
>> I am wondering if there is a way to hack the source to change the midi
>> pitch values which are output when it renders.  I want to do this so
>> that I can remap those values to arbitrary frequencies for microtonal
>> playback in a retunable software synth like puredata.
>> 
>> For example, say I wanted to remap the following note names:
>> c cis des d
>> so that when it is compiled, the following midi pitch values will be written:
>> 60 61 62 63
>> or perhaps:
>> 60 60.67 61.33 62
>> 

It seems like this should be possible, but I haven't worked with the code at
all.

> 
> Personally I would like lily to have much more sophisicated midi capabilities.
> 
> For instance It would be nice if markup could be tied to program change events
> so, for instance, markup like "pizz" could not only be printed in the score
> but also change the midi instrument.
> It would also be nice if things like staccatto were renereabl in midi, and,
> perhaps "tunable".
> 

Yes, that would be wonderful.

>> or whatever.  It really doesn't matter, since pd can map
> those to any
>> frequency I like!  All I really need is to set discrete values for
>> *each* accidental (no enharmonic equivalents) and 'white notes'.
>> Octave doubling is fine.

If all you need to do is is set cis to be a different pitch from des, that's
quite easy.  I think that all you need to do is set different alterations in
the file lily/pitch.cc.  Of course, you will need to be able to compile
lilypond to do this.



>> 
>> I don't know anything about pd's internals, but I have some rusty
>> programming knowledge.  I would just like to know if such a thing
>> would be possible, and if so, where I should start looking.  Thanks so
>> much!
> 
> I don't think this can be done from lily at the moment. I too have some rusty
> programming knowledge.
> 
> In the mid 80's I wrote some Z80 assembler code to control a midi interface.
> So I would be quite interested in a re-write of the lily midi code. But I am
> not sure how many people would be interested.

I think that improved MIDI output is one of the most-requested enhancements
for LilyPond.  There would be *lots* of people interested in better MIDI.
If you were interested and willing to take it over, that would be great.

The problem is that right now, nobody is a champion for MIDI output.

Thanks,

Carl