print-dot and print-leger attribute questions

[lemzwerg]

The specification provides the following documentation for these two <note> attributes.

• print-leger: Indicates whether leger lines are printed. Notes without leger lines are used to indicate indeterminate high and low notes. It is 'yes' if not present unless print-object is set to 'no'. This attribute is ignored for rests.
• print-dot: Controls the printing of an augmentation dot separately from the rest of the note or rest. This is especially useful for notes that overlap in different voices, or for chord sheets that contain lyrics and chords but no melody. If print-object is set to 'no', this attribute is also interpreted as being set to 'no' if not present.

My questions are as follows.

1. This is especially useful [...] for chord sheets that contain lyrics and chords but no melody. I have no idea what this means, and it would be great if someone could provide an example – or a better description.
2. It's clear to me what happens if print-object is set to 'yes'. However, what happens if I set print-object to 'no' and print-dot to 'yes'? Does this hide the note (together with its stem, flag, and ledger lines) except the dot(s)?
3. Similarly, what happens if print-object is set to 'no' and print-leger is set to 'yes'? Is it expected that I see the ledger lines, while the note, the stem, the flag, and the dot(s) are hidden?

[lemzwerg]

BTW, the description of print-lyric is as follows.

• Controls the printing of a lyric separately from the rest of the note or rest. This is especially useful for notes that overlap in different voices, or for chord sheets that contain lyrics and chords but no melody. If print-object is set to 'no', this attribute is also interpreted as being set to 'no' if not present.

This is almost the same text as for print-dot, but here the comment regarding chords make sense. So maybe this is a copy-and-paste error? Looking into file schema/common.mod, I find the following comment, which makes much more sense to me, and which strengthens my suspicion.

• The printout entity allows a way to specify not to print an object (e.g. note or rest), its augmentation dots, or its lyrics. This is especially useful for notes that overlap in different voices, or for chord sheets that contain lyrics and chords but no melody. For wholly invisible notes, such as those providing sound-only data, the attribute for print-spacing may be set to 'no' so that no space is left for this note. The print-spacing value is only used if no note, dot, or lyric is being printed.

  By default, all these attributes are set to 'yes'. If print-object is set to 'no', print-dot and print-lyric are interpreted to also be set to 'no' if they are not present.

This seems to answer question 1. However, it is still unclear what to do for questions 2 and 3...

[infojunkie]

My interpretation and recommendation would be to ignore any @print-XXX attribute if the same element's @print-object = 'no'. Maybe also the same for @print-object = 'no' in parent elements? I need to dig up past issues where such hierarchical issues are raised.

Given the recurrence of such visibility-related questions, I've created a visibility tag and I reiterate that if you are interested, @lemzwerg , I would sollicit your help to help tag the issues.

I would also be enclined to adjust the documentation of print-XXX to make it explicit that print-object = 'no' overrides other print-XXX = 'yes'. I'd appreciate confirmation or counter-examples here.

[lemzwerg]

Thanks for the reply; I agree with your interpretation, and hopefully we see a clarification in the specs soon 🙂

The hierarchy problem of print-object is tracked as issue #592, which in turn links to other related issues.

Right now, I don't have sufficient time to assist with tagging, unfortunately, but this will change in April or so (i.e., after the next major LilyPond release)!

[mdgood]

No, all the printout entity attributes work the same way - they override the top-level object value if different. This was probably clearer when the schema was the spec, since we didn’t include entities in the documentation.

[infojunkie]

This is especially useful [...] for chord sheets that contain lyrics and chords but no melody. I have no idea what this means, and it would be great if someone could provide an example – or a better description.

A suggestion to have better chance to get answers for such repertoire questions: I've seen plenty of such topics discussed on Stack Exchange's Music: Practice & Theory forum. The community there seems to be more active than on this repo.

[lemzwerg]

I'm closing this as answered – issue #592 provides all the necessary details.