Regression in v1.8.4: Certain tracks fail to render Numbered Notation (Jianpu) compared to v1.6.0

[yezhenbiao]

Describe the bug
I am experiencing a rendering issue where certain tracks in some Guitar Pro files cannot be displayed in Numbered Notation (Jianpu). When I trigger the switch to Numbered Notation via the API, the specific track fails to render completely (the staff area becomes blank).

I have tested this on multiple random songs and the issue is consistent. However, with the exact same code logic on v1.6.0, it works perfectly. The issue only occurs on v1.8.4.

To Reproduce

1.Load a Guitar Pro file that contains tracks with this issue.

2.Use the following standard API logic to switch to Numbered Notation:

player.tracks.forEach((track) => {
track.staves.forEach((staff) => {
if (staff.isPercussion) return;

    staff.showTablature = false;
    staff.showStandardNotation = false;
    staff.showNumbered = true;
});

});
player.updateSettings();
player.render();

3.The track fails to render on v1.8.4, but renders correctly on v1.6.0.

Expected behavior
The track should successfully render in Numbered Notation.

Additional context

Note: I have already ruled out lyrics as the cause. Even tracks without lyrics fail to render in Numbered Notation on v1.8.4.

Possible cause: I noticed that v1.8 introduced a completely new handling of beams and stems, along with other layout changes. It seems these new rendering engine updates might have introduced a regression that breaks the layout logic for Numbered Notation in certain edge cases.

Version Information

OS: Windows (Chrome/Edge browser)

alphaTab version: v1.8.4 (Broken)

alphaTab version: v1.6.0 (Working perfectly)

[yezhenbiao]

test.zip
For example, in the attached score, the Solo track within the score cannot be switched to numbered musical notation.

[Danielku15]

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