Allow switching between ordinary and oversized notehead variants

[MichaelGerecke]

Issue type

Engraving bug (incorrect score rendering)

Description with steps to reproduce

MuseScore fails to honor the explicit stem attachment points defined in the glyphsWithAnchors section of SMuFL metadata JSON files for third-party fonts.
This causes ugly stem alignment issues with specific third-party fonts like MTF-Cadence (where upward stems render shifted towards the center of the notehead).

Steps to Reproduce

1. Install a third-party SMuFL font.
2. Open the font's metadata .json file and manually change the glyphsWithAnchors coordinates for noteheadHalf to absurdly extreme values.
3. Open MuseScore Studio and create a new score.
4. Go to Format → Style and load the modified SMuFL font.
5. Input a half note into the score.

Expected behaviour

The stem should be heavily offset and detached from the notehead, following the high coordinate values injected into the JSON.

Actual behaviour

The stem remains locked in its original position.

Supporting files, videos and screenshots

video.mp4

In the attached video, I tested two different fonts. Eugene can be downloaded for free at https://mikkopatama.com/eugenefont/, while MTF-Cadence is a commercial font. Please note that the beam thickness was altered solely to demonstrate that MuseScore is indeed interpreting the font's JSON metadata file but ignoring the stem anchor adjustments.

In which versions of MuseScore Studio is this issue present?

4.6.1 (4.6.0 was not tested) - 4.7.4 and 4.7-/master-nightlies

Regression

I was unable to check

Operating system

Windows 11

Additional context

A similar issue was previously reported in #29734 and closed as completed in #29838, but this bug still exists.

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

[MichaelGerecke]

'glyphBBoxes' values seem to be ignored as well, since changes for noteheadHalf have no effect.

[Jojo-Schmitz]

Might relate to #29879/#29882

[MichaelGerecke]

Update: Cause identified

Contrary to my initial assumption, the JSON values for the stem anchors are not being ignored — they are simply being overwritten by the values of the oversized variants.

This behavior stems from the GLYPHS_WITH_ALTERNATES array in engravingfont.cpp. Here, the oversized noteheads are explicitly mapped back to the standard notehead base IDs, which overwrites all previously correctly parsed standard SMuFL metrics.
I suspect this was an intentional design decision! While it works quite well for some fonts (like Bravura), it breaks completely for others (like MTF-Cadence).

I see the following ways to address this issue:

1. JSON-Tinkering (User): Manually modifying the font's JSON file to delete all oversized variants (fastest, but a bit hacky).
2. Local fork (User): Modifying the source code to globally remove these substitutions (not ideal, as it affects all scores and all fonts).
3. Whitelisting (Developer): Extending the source code to determine which fonts should leave standard noteheads untouched (hard to maintain).
4. Style Setting (Developer): Exposing a style setting (e.g., "Use oversized noteheads"). This option could also be imported via stylesheets: MTF-Cadence is shipped with a dedicated .mss file, allowing designers to package and enforce this preference cleanly (best option imho).

[MichaelGerecke]

I implemented a checkbox to opt in or out of oversized noteheads and submitted it as a suggestion via Pull Request #34895. Feedback and reviews are very welcome!

[Jojo-Schmitz]

Without (naming) a freely available font to reproduce this issue, a fix can't get verfied, MTF-Cadence is not free(ly available)

[MichaelGerecke]

Yes, that's true. Unfortunately, I'm not (yet) aware of any other font that has such broken rendering in oversized mode as MTF-Cadence.

My approach in this PR was to first allow choosing the notehead mode and disable oversized mode by default (assuming this provides a satisfactory rendering for the majority of fonts). You can test the checkbox functionality with Bravura and for example Eugene (OFL).