#1636 Three half-notes in 4/4 measure

[Mark R. Rubin]

Attempting to create dyads (two-note "chords") with a stem up on the upper voice and stem down on the lower results in three consective half-notes in a 4/4 measure in the Notation Editor.

Steps to recreate:

• New composition, add a two measure segment, open in Notation Editor.
• All defaults: Treble clef, 4/4 time signature, C major key signature.
• Draw tool, half-notes.
• Add G above middle C on first beat of measure one. Whole note rest disappears, replaced by half note followed by half note rest.
• Add C above the G, still on beat 1, i.e. a G-C dyad. Both stems upward, overlaid.
• Move to beat 3, add E above middle C (removes half note rest).
• Add A above the E, still on beat 3. (E-A dyad.) Again both stems are up.
• Attempt to make E stem down and A stem up. Change to select tool, select the E.
• Note -> Stem Down. Both stems are now down (wrong, stem on A should still be up).
• Select the A.
• Note -> Stem Up. Stem is up but A has moved from beat 3 directly over the E to fictitious beat 5.
• Select the C on beat 1. Edit -> Delete. Still three half-notes in 4/4 measure, G, E, A.
• Same result if only one measure in segment -- use of two measures shows that A is not being pushed to second measure leaving correct two half-notes in measure one.

Despite the impossible measure in the Notation Editor, the underlying document seems to be OK as per the Matrix Editor and export via Lilypond.

Tested with [6a0662] and 21.12

See attached three_half_notes.rg file and notation_editor.png screengrab. Also matrix_editor.png screengrab and lilypond_export.pdf. FWIW, I was trying to do something like four_part_harmony_stems.png from the lesson at https://www.schoolofcomposition.com/beginners-guide-to-4-part-harmony/.

[Yves Guillemot]

What you observed is the notation editor inability to display polyphony in only one segment.
A workaround exists: use one segment for each voice and place these segments on the same track (see attachment A.png).

The rest can be set invisible and, depending of the RG notation configuration, be displayed in gray which works (see B.png), or not be displayed at all which doesn't work very well (see C.png).

In the three cases, export to LilyPond works fine (see LA.png and LBC.png).

Although moving a rest vertically in the notation editor is possible with:
"Adjust ->Fine positioning -> Push Up/Down",
this is really tedious.

Now thinking to it, moving a note horizontally in your example is also possible with:
"Adjust ->Fine positioning -> PushLeft/Right".
I can't see this as a good solution.

I personally don't use the notation editor as a WYSIWYG tool.
Correctly printing out is what really matters and LilyPond does it fine.
(This is not to say that everything if perfect: there is of course a lot of room for enhancements).

[Mark R. Rubin]

Thanks, Yves. Those are interesting workarounds which I wouldn't have thought of. And in the example I was using (four_part_harmony_stems.png) there aren't any rests so the worst of the problems go away.

Editing two coincident segments on the same track and staff works but is a little clumsy. One of the nicest things about working with multiple segments/tracks in Notation is that moving the mouse from one staff to another automatically changes the active segment without having to use the scrollwheel, and you lose that with two segments on the same track. (BTW, I'm working in FR #504 on improving the Matrix Editor's requirement to use the scrollwheel.)

I think the basic problem I'm reporting here isn't the impossible three half-notes in one measure but that doing "Note -> Stem Up" or "Stem Down" affects all stems on the same beat instead just the one on the selected note. My knowledge of music theory is pretty limited but I thought polyphony was just multiple notes sounding at the same time (like chords, which the Notation Editor does fine) as opposed to counterpoint which means simultaneous notes in different voices/instruments. And that the one stem up, one stem down thing was specifically to show counterpoint on a single staff. (Maybe also for when the left hand in a piano piece temporarily moves up from the bass clef staff on the combined "grand staff" and plays notes up in the treble cleff staff.)

Things like this are why I don't use Notation much. The Matrix Editor never lies. ;) I do find Notation useful when hand-copying from sheet music which is how I came across this bug. I understand what you're saying about the Notation Editor just being a rough preview for Lillypond but I think being able to create the three half-notes in RG, regardless of how and why it's done, is a pretty glaring bug.

Like I said, my heart's in the Matrix Editor so I'm unlikely to work on this, or better yet donate money for someone else to do it. Basic free open-source software policy. I understand that implementing stem up / stem down could possibly be a difficult fix to make (I've come across plenty of conceptually simple changes in the RG codebase that turn out to be very complicated), but I thought it was worthwhile filing this for future reference.

Thanks again for taking the time to look into it and provide the insights and workarounds.