Mixer Mute and Solo Selection Behavior Improvements

[Arnesfield]

Your idea

The mixer mute and solo selections currently change behavior whenever a measure is selected. Update the existing behavior with the following:

1. The user should ALWAYS be able to toggle on and off both the mixer mute and solo buttons regardless of current or future measure selections.
2. Never disable the mixer mute and solo buttons if one or the other is toggled on/off. Both buttons should be enabled/clickable at all times.
3. Measure selections should NEVER toggle the any mixer solo selections. Instead, perform a temporary playback override using the user's mixer settings as a base ONLY WHEN a measure is selected, and only those selected parts will have playback.

To get the list of parts that have playback:

1. Let A be the list of all parts.
2. Let B be the list of only solo parts from A. If there are none, let B be the same as A.
3. Let C be the list of only unmuted parts from B.
4. For the list of parts that will have playback: a. If there are no selected measures, let C be the list of parts that will have playback. b. If there are selected measures, the list of parts from selected measures will have playback regardless of C.
5. Exported audio should follow the user mixer settings (list of parts from C) regardless of other filters (e.g. measure selections).

Problem to be solved

1. Currently, the mixer mute button is disabled whenever a measure of a part other than itself is selected.

https://github.com/user-attachments/assets/24d1362c-050f-46b2-9868-df2e151043ab

2. The mixer solo button is disabled when mute is active. It is also toggling the solo button off.

https://github.com/user-attachments/assets/7ee05890-1bdf-4abf-850c-90911a01a12b

3. The mixer solo selection is removed whenever a measure of a part other than itself is selected.

https://github.com/user-attachments/assets/9e7a4d27-bffb-4b77-bfda-7effa6c7e2e1

Some thoughts:

• The measure is the arguably easiest element to select on the score as it occupies a lot of space compared to notes and lines.
• Having toggled the mixer solo selections for a couple of instruments only for them to be deselected from a misclick is just not good behavior.
• Allow the user to always be able to toggle mixer mute and solo selections and the application should only use them as a base for what parts will actually have playback rather than be directly linked to the playback itself.
• Think of the user mixer settings as the default values, but of course it goes through some checks and filters (e.g. measure selection) and only then you get the list of parts that will have playback.
• Exporting audio shouldn't be affected by this temporary playback override and should always follow user mixer settings.

Prior art

LMMS allows selecting both mute and solo for parts, but MuseScore 4 has more nuance with this functionality like allowing multiple solo selections and measure selections.

Additional context

No response

Checklist

• [X] This request follows the guidelines for reporting issues
• [X] I have verified that this feature request has not been logged before, by searching the issue tracker for similar requests