Re: Part combiner warning about simultaneous breathing

[David Kastrup]

Devon Schudy <address@hidden> writes:

> David Kastrup wrote:
>> My guess would be that the whole articulation mechanism might be
>> changed in a manner that partcombine no longer is able to consider two
>> articulations as mergeable.  In that case, it would likely be more than
>> just breathings which are affected.
>
> Yes: it's because that commit added the midi-length property to breath
> marks (and some articulations), whose value is a function, so
> partcombine can't tell they're identical.
>
> The old definition of \breathe (without the offending property) gives
> no warning:
>
> breathe =
>  #(define-music-function (parser location) ()
>     (_i "Insert a breath mark.")
>    (make-music 'BreathingEvent))
>
> The simplest fix is to make \breathe use the same (eq?) closure
> instead of a new one each time, so partcombine can merge the breaths:
>
> #(define (breath-midi-length len context)
>   ;;Shorten by half, or by up to a second, but always by a power of 2
>   (let* ((desired (min (ly:moment-main (seconds->moment 1 context))
>                        (* (ly:moment-main len) 1/2)))
>          (scale (inexact->exact (ceiling (/ (log desired) (log 1/2)))))
>          (breath (ly:make-moment (expt 1/2 scale))))
>     (ly:moment-sub (ly:make-moment (ly:moment-main len)) breath)))
>
> breathe =
> #(define-music-function (parser location) ()
>    (_i "Insert a breath mark.")
>    (make-music 'BreathingEvent
>      'midi-length breath-midi-length))

Wouldn't it be the proper cure to just revert to the old definition of
breathe and move the definition of midi-length into
scm/define-music-types.scm?

It does not appear like putting such a default value in the mutable
properties makes sense in the first place.

-- 
David Kastrup