Add shortcut for Chord Inversions

[regulus79]

This PR adds the ability to invert a selection of notes in the PianoRoll, where the top note moves down n octaves/bottom note moves up n octaves. This feature works on selections of notes too, moving all notes on the min/max key up/down. It also works on microtonal scales which may have different octave sizes.

Edit: The keyboard shortcuts have been reversed. Now Shift+U is for Upward inversion.

The icons probably need to be changed. Also I think the two options might take up too much space in the menu. I was thinking of adding a sub menu, but I'm not sure Qt allows that.

2025-02-16.19-43-23.mp4

[zonkmachine]

Code looks fine and the functions works as intended. I've thrown complex note patterns at it and you can invert the patterns up/down and it seem to end up where you started. I don't think you can expect it to work that well for all combinations but it may well be the case. I don't think it has to though as there is always Ctrrl+Z. Job well done.
Please note that if you push the notes up/down far enough they will 'clip' at the top/bottom note and will no longer be a chord but a single note in the end (invert it up 10 octaves and down again...). This may or may not be desired but is not a part of this PR.

[szeli1]

I'm not sure Qt allows that.

If it is a context menu, then qt will allow it.

[szeli1]

I reviewed and tested this and it works as intended. I'm not sure where this would be useful, but if there is a use for this, then this can be merged.

[regulus79]

If it is a context menu, then qt will allow it.

It seems that it's not exactly a context menu(?) The actions are added directly to the tool button with noteToolsButton->addAction(), instead of adding them to a menu and adding the menu to the button. I tried making a sub menu and adding it to the button, but that didn't work. I think there is a function to add a whole menu object instead of adding action by action, which might work. I haven't tried that yet, but in any case that would probably be for a separate PR.

[bratpeki]

I don't know how I feel about this feature, mainly since Ctrl+UpArrow/Ctrl+DownArrow exist. I feel like it's bloating our context menu but not giving a lot in return.

I dunno, if users are pushing for it to be in LMMS, I'll gladly test it, but I personally am not a big fan.

[zonkmachine]

I don't know how I feel about this feature, mainly since Ctrl+UpArrow/Ctrl+DownArrow exist

This again. How does these features compare?

I'll gladly test it, but I personally am not a big fan.

You haven't tested it?

I haven't tried that yet, but in any case that would probably be for a separate PR.

Separate PR is fine with me. Merge is fine by me.

[bratpeki]

This again. How do these features compare?

One is a subset of the other, which is why I feel like we're adding in a feature that already "exists".

You haven't tested it?

No, not yet. I would like to give my opinion and talk about the feature before testing.

[regulus79]

I don't know how I feel about this feature, mainly since Ctrl+UpArrow/Ctrl+DownArrow exist. I feel like it's bloating our context menu but not giving a lot in return. ... One is a subset of the other, which is why I feel like we're adding in a feature that already "exists".

Ctrl+UpArrow/Ctrl+DownArrow shifts the whole selection up/down an octave, while this feature shifts the chord up one note at a time. But I get what you mean, that you can get this same effect by selecting each note you want to move, and then using Ctrl+Up/Down. However, I found that to be quite time consuming when building chord progressions. Also, I personally think it's useful to be able to quickly invert chords to get a "new sound" out of them, which can be fun for getting new ideas for a chord progression.

But I do agree it's kinda bloating the context menu lol. I can do something about that in a separate PR if it becomes a large enough issue.