Page layout different after reopening file with custom scaling

[dbenzhuser]

Issue type

Opening/saving issue

Description with steps to reproduce

I use Spatium / staff space in the page settings dialog to make part scores better fit on a single page. After saving and reopening a file, the layout is not the same any more: often times there is either an additional page with a few measures, or empty space in the last line on the page.

Just manipulating the staff space setting (change the value, immediately change it back) resolves the issue temporarily. I have to do this everytime I want to print a part score or recreate PDFs.

See attached file (Spatium Bug.mscz):

• Open the file
• Open Trombone part score
• Part score is displayed on 2 pages (2 measures on second page)
• Open page settings
• Modify staff space value, then reset it (ex: focus in text field, mouse wheel up, mouse wheel down)
• The score now fits one page perfectly
• Save the file, then reopen it
• Part score is again displayed on 2 pages 😞

Expectation:

• Part scores should look the same after saving and reloading
• The same value for staff space should not result in a different page layout

Supporting files, videos and screenshots

Layout fits on one page:

Reopened the file, now it no longer does, settings are unchanged:

Spatium Bug.zip

What is the latest version of MuseScore Studio where this issue is present?

OS: Windows 11 Version 2009 or later, Arch.: x86_64, MuseScore Studio version (64-bit): 4.4.4-243461245, revision: github-musescore-musescore-2232670

Regression

I was unable to check

Operating system

Windows 11

Additional context

No response

Checklist

• This report follows the guidelines for reporting bugs and issues
• I have verified that this issue has not been logged before, by searching the issue tracker for similar issues
• I have attached all requested files and information to this report
• I have attempted to identify the root problem as concisely as possible, and have used minimal reproducible examples where possible

[dbenzhuser]

With the nightly (MuseScore-Studio-Nightly-latest-master-x86_64.7z, 2025-01-25 03:24) the same issue is still present, but different values are needed for some reason.

Changing the staff space to 1.700mm (from 1.550mm in my example file) leads to the same behavior: The trombone part fits on one page, but after reopening the file it no longer does. Temporarily changing the value "fixes" it for the curren session.

[MarcSabatella]

FWIW, it doesn't seem to be a case of things being off on the first edit and then fixing themselves - no simple edits will cause the layout to fix itself. You can see the issue on the very first system when comparing the score to the part, which have identical (as far as I can tell) formatting but the score fits one more measure. Doing an edit that forces a complete relayout (e.g., Ctrl+A, Ctrl+Up, Ctrl+Down) does not change this. It also does not appear to be a roundoff error - I can increase stretch for a measure in the score without pushing a measure to the next system, and decrease stretch in the part without allowing a measure to be added to the first.

However, I'm not sure the issue is actually about spatium specifically. Visually, the score and part already do appear to be the same size. And I can force the extra measure to fit by changing the minimum note distance in Format / Style / Measure to something else and then back. In fact, even increasing it one notch of the spin box (from 0.25 to 0.35) suddenly allows everything to fit. Similar for the minimum measure width and other settings in that dialog. So I suspect it might actually be those settings that are somehow not being honored correctly on load.