Bad (negative) default height for fixed spacer if added to last staff of score

• Feb 15, 2021 - 17:32
Reported version
3.0
Type
Functional
Frequency
Once
Severity
S4 - Minor
Reproducibility
Always
Status
PR created
Regression
No
Workaround
Yes
Project

I am new to muscore and very please with this tool. Thank you so much for creating this.

I am working on what I hope will be an exercise book for cello intonation.
After using the "Section Break" I could not add measures via "Append" or "insert" more that 2 and only (one at a time). Also when I tried to copy and paste bars from the previous line above the section break , instead of the bars being added to the end of what I had it just merged the notes from all the bars together making a mess.

Thanks for listening

Attachment Size
The Ringer.mscz 10.74 KB

Comments

Regression No Yes
Severity S1 - Blocker S2 - Critical
Priority P1 - High

Deleting the sction break also results in pretty much a catastrophy

Title copy and paste or adding measures after a section Break does not function as expected. copy and paste or adding measures after negative size fixed spacer does not function as expected.
Title copy and paste or adding measures after negative size fixed spacer does not function as expected. copy and paste or adding measures after a section Break does not function as expected.
Status active needs info
Workaround Yes No

Seems the score is in a bad state somehow; the question is, how did this happen? I can't recreate a case like this from scratch. Something seems already wrong with the score; something weird with a hidden duplicate clef and also a spacer in the first bar after the break. If I delete those things are better.

Title copy and paste or adding measures after a section Break does not function as expected. copy and paste or adding measures after negative size fixed spacer does not function as expected.
Status needs info active
Workaround No Yes
Title copy and paste or adding measures after negative size fixed spacer does not function as expected. Issues with negative height fixed spacer.
Regression Yes No
Severity S2 - Critical S3 - Major
Status active needs info

Assuming the fixed spacer was placed there on purpose, I guess we don't need more info. But, this would not have produced good results in any other version either. Basically, the new measures are being laid directly on top of the old. That's not even a bug, it's just doing what is being asked for - placing the next system directly on top of the previous.

So as far as I can tell, it's only a bug if something caused that negative spacer to appear uncalled for. And in that case, we'd need steps to reproduce that issue.

Title Issues with negative height fixed spacer. Bad (negative) default height for fixed spacer if added to last staff of score
Severity S3 - Major S4 - Minor

Now I see how this probably happened. When you add a fixed spacer to a score, it's supposed to calculate the current distance to the next staff and size itself appropriately so it has no effect immediately but is then ready for adjustment in either direction. This works fine most of the time (even with vertical justification on) but seems to fail if you add one to the last staff of the last system of the score - it sizes itself to reach the top of that same system.

Not a new behavior - it's been the same since fixed spacers were introduced at 3.0

When looking (again) into this issue a question arises: What is the intended behavior for a fixed negative spacer on the last staff? Should it push the staff below the page bottom/margin? Or should the page margin always be honored?
The PR I'm working on now will at least create a correct fixed spacer when placed on the last staff of a page but I think is better if also the behavior for negative values is correct.

With PR #7756 (or PR #7757 for master) a negative spacer never pushes a staff below the Music Bottom Margin. Is this the behavior between vertical adjustment of staves and the pre-3.6 spreading is identical.