Re: note head direction not automatically rearranged for two adjacent pitches when two voices are used instead of a chord

[Soo Lee]

I did try \partCombine but it doesn't work for me. I need a more manual control because of subtle differences between the two voices (e.g. grace notes and voice-specific ties and slurs). For example, the notes in the example below are not auto-merged as chords because of these differences.

instrumentOne = {

\time 3/4

\relative c'' { \partial 4 gis4( e'2. dis) c8[ d e \acciaccatura g f g f] }

}

instrumentTwo = {

\time 3/4

\relative c'' { \partial 4 gis4~ gis2. fisis e8[ f g a b a] }

}

<<

\new Staff \partCombine \instrumentOne \instrumentTwo

>>

On Tue, May 24, 2022 at 9:46 PM Jean Abou Samra <jean@abou-samra.fr> wrote:

Le 24/05/2022 à 14:43, Jean Abou Samra a écrit :
> Le 24/05/2022 à 13:36, Soo Lee a écrit :
>> I isolated these notes to create a tiny example, but the context
>> suggests that it makes more sense to view them as two voices. This is
>> a Chopin piece and unlike e.g. Bach, two voices often are expressed
>> like a chord. I wanted to avoid going back and forth between one
>> voice and two voices too often.
>> I guess it is possible to just use a chord in this case. I'll try to
>> think about other work-arounds. However, I think an ideal behavior
>> would still be to automatically rearrange the note head direction in
>> a case like this.
>
>
>
> I don't think this syntax is the right tool for your
> purpose. With \new Voice, you're telling LilyPond that
> you want separate voices. With \voiceOne and \voiceTwo,
> you specify stem directions for both voices. Then, with
> \stemUp, you kind of contradict what you just said. It's
> tricky for LilyPond to interpret this input. Rather, I
> suspect you want to use the part combining feature in
> order to merge notes in one single stem when the rhythm
> is the same.
>
> https://lilypond.org/doc/v2.22/Documentation/notation/multiple-voices.html#automatic-part-combining
>
>
> Jean
>


To expand: consider

\version "2.22.2"

\new Staff <<
   \new Voice { \voiceOne g''8 8 8 8 }
   \new Voice { \voiceTwo \once \stemUp a,8 a'8 \once \stemUp a,8 a'8 }
 >>


If the \stemUp made the stems merge, this use case would no longer work.

Jean