Re: Rolls and ruffs

[Mats Bengtsson]

As you noticed, I know nothing about drum notation and I think this
goes also for the main hackers of LilyPond. So, any input you have
on suggestions are welcome, not the least if you can assist yourself
with the implementation.

Peter Mogensen wrote:
> Mats Bengtsson wrote:
>
> > Did you try the following?
> >
> >  \time 6/8
> >   c'8 r c8:32 ~ c8 c c |
> >   c4.:32 ~ c4.:32 ~ |
> >   c8 r c:32 ~ c c c |
> >   c4.:32 ~ c4 c8:32 ~ |
> >   c8 r c \acciaccatura d c r c
>
>
> Yes. But it doesn't give the result I'm looking for. It's _looks_ like 
> the wanted engraving, but it's not perfect. It's a slightly different 
> concept than tremolos.

Comparing your example to what I sent, I note that I forgot to add
some beams (these have to be done manually because of the repeats):
 \time 6/8
  c'8 [ r c8:32] ~ c8 c c |
  ...

> Rolls are denoted with 3 strokes.
> Ruffs are denoted with 2

Like c8:16 versus c8:32 ? Or did you mean the 2 strokes in addition to
the beam like in c'8 [ r c8:32] ?

> The strokes across the stem is usually more light than a tremolo.
> This gives a nicer looking roll:
>
>       \property Voice.StemTremolo \set #'beam-thickness = #0.1
>       \property Voice.StemTremolo \set #'beam-width = #1.5
>       \clef percussion
>       sn4:32( sn8) r8
>
> However... when I try that with ruffs, the strokes align to the beam and 
> becomes horizontal when the beam is. That's not the intention.
>
>    \property Voice.StemTremolo \set #'beam-thickness = #0.1
>    \property Voice.StemTremolo \set #'beam-width = #1.5
>    c8:32~c8

That's the normal notation for tremolos, which as you have pointed out
is not the same as rolls/ruffs. For the moment, this behaviour is
hard coded in the LilyPond implementation, but it looks as if it should
be trivial to add a property to let you keep the tilted strokes also
when you have a beam.

> Rolls generally a just drum rolls lasting as long as the note. No one is 
> counting how many times the stick hits the snare.
> Ruffs are (most often) 5 beats (the 5th being the tied note). In the 
> above code there will only be 3 beats.

In the MIDI output, you mean?

> > For the MIDI output, it's possible to unfold tremolo repeats
> > as shown in
> > http://lilypond.org/doc/v2.2/input/regression/out-www/collated-files.html#repeat-unfold-tremolo.ly 
> >
> > See also the mailing list archives, where a related question was
> > answered earlier today.
>
>
> I've read about unfolding tremolos and I've found mails on the list 
> about it. It's not what I want though.

In what sense? If you want something else than the exact 32:nd notes in
the MIDI output, I'm sure you could hack together a solution that uses
\repeat unfold 6 { c32*2/3 } or whatever in the MIDI output (if you are
good at Scheme programming, it shouldn't be hard to make a nice function
that makes this replacement in the MIDI version), but you should note
that the MIDI support in LilyPond has never been intended for
professional quality MIDI output. The level of ambition is to make it
useful for proof reading (proof "hearing"). For example, features such
as trills are not taken into account in the MIDI output.

  /Mats