Re: custom metronome-markup procedure causes weird goops-error

[Neil Puttock]

On 25/04/2008, Valentin Villenave <address@hidden> wrote:
> 2008/4/25 Valentin Villenave <address@hidden>:
>
>
>  >  Here's my code; it works quite well on simple examples, but on complex
>  >  scores it triggers an error I've never seen:
>
>
> OK, I've fixed it; it actually involved using a different name for the
>  metronomeMarkFormatter procedure:
>
>  mov =
>  #(define-music-function (parser location texte duration count music)
>  (string? string? integer? ly:music?)
>  (define (format-movement-markup dur count context)
>     (make-line-markup
>      (list
>       (markup #:mvt texte #:hspace 1)
>
>       (make-simple-markup  "(")
>       (make-general-align-markup Y DOWN (make-smaller-markup
>                      (make-note-by-number-markup (ly:duration-log dur)
>                                                  (ly:duration-dot-count dur) 
> 1)))
>       (make-simple-markup  "=")
>       (make-simple-markup (number->string count))
>       (make-simple-markup  ")"))))
>
> (make-music 'SequentialMusic 'elements
>       (list (make-music 'ContextSpeccedMusic
>               'context-type 'Score 'element
>               (make-music 'PropertySet
>                 'value format-movement-markup
>                 'symbol 'metronomeMarkFormatter))
>
>             (make-music 'ContextSpeccedMusic
>               'context-type 'Score 'element
>               (make-music 'SequentialMusic 'elements
>               (list (make-music 'PropertySet
>                      'value (ly:duration-length (string->duration duration))
>                      'symbol 'tempoWholesPerMinute)
>                     (make-music 'PropertySet
>                      'value (string->duration duration)
>                      'symbol 'tempoUnitDuration)
>                     (make-music 'PropertySet
>                      'value count
>                      'symbol 'tempoUnitCount))))
>
>                      music
>
>                      (make-music 'ContextSpeccedMusic
>               'context-type 'Score 'element
>
>               (make-music 'PropertySet
>                 'value format-metronome-markup
>                 'symbol 'metronomeMarkFormatter)))))
>
>
>  Now it works perfectly -- sorry for the noise!

That's good, but there are two problems with it; one quite serious if
you value having MIDI output.

First, you haven't set tempoWholesPerMinute properly, unfortunately
(it's the same problem I was scratching my head about in the original
thread):  the combination of the note value and beats per minute needs
to be converted to a moment. In the example

\mov #"Largo" #"2." #140

your code sets tempoWholesPerMinute to (ly:make-moment 3 4 1 1),
ignoring the beats-per-minute value, whereas it should be converted to
an integral value, i.e. (ly:make-moment 105 1 0 1) or (ly:make-moment
210 2 0 1).

Second, unlike the helper function parse-simple-duration,
string->duration doesn't account for durations longer than a semibreve
since they can't be directly converted to a number.

So, in conclusion, close but no cigar. ;)

Regards,
Neil