fix #279471 Set note cutoff length

[blackears]

Adding dialog to allow user to specify a fraction of a beat that notes should be cutoff at. Right click in the paino note area and select 'Note Tweaker' to activate dialog.

[shoogle]

A whole new dialog just for one setting? Surely there is a better way to do this.

BTW, does this change the offtime of individual notes or the gatetime of all notes?

[dhfx]

Will this advance the off-time equally for all notes in a select range, regardless of the notational duration of the notes?

[shoogle]

Ok I found the issue and original discussion and now I have a better idea of what this is trying to do. The best explaination is given by @dhfx. You said:

There are actually 2 parts to this:

1. to shorten the note by a fixed time amount [..] e.g. a certain fraction of a beat, or even as an absolute time interval (say 0.1 sec), INSTEAD OF as a fraction of the notation length as at present;
2. to be able to apply this to all notes selected as a group.

Currently the user can only adjust the length of the the note as a fraction of its duration (out of 1000), and they can only do it for one note at a time.

I think the best way to solve this would actually be to start with (2) and enable the user to adjust the properties of multiple notes at once. This doesn't require changing the internal representation and it doesn't require changing the UI. It also would make the most difference to the end user in terms of time saved.

(1) is best solved by a plugin, or by adding a checkbox to the pianoroll editor to allow the user to choose between relative and absolute units.

[blackears]

This adjusts the offtime. Gatetime is Musescore's default way of tracking this, and this figures out how to set the gatetime to get the desired offtime.

The window seemed a simple way to pull everything together and would be a good location to add more note fiddling tools to in the future. It would be hard to cram too many more UI controls into the existing piano roll interface.

[dhfx]

Why exactly is there "no easy way to wedge this into the existing piano roll editor" - is it a question of space on the UI, or of needing additional hooks in the code? If it's space, why not modify the Len: control together with something to change the way it is used, either (1) as presently, (2) to advance the cutoff as a fraction of a beat, or (3) to advance the cutoff by an absolute time interval. That "something" could be a dialog box - or simply replace the "Len:" text by a button that toggles through the choices and retains the last setting, with the (abbreviated) name of the choice as varying text on the button, e.g., "Length", "Off adv rel", "Off adv abs" (or some such).

[shoogle]

The inability to edit multiple notes at once in the pianoroll editor is a serious limitation that needs to be addressed (but it's not urgent).

However, when it comes to shortening lots of notes by a fixed interval I can't help but feel that this is the wrong way to go about it. I've given my reasoning in the original forum discussion. See https://musescore.org/en/node/278509#comment-875761

[dmitrio95]

Needs actualization for current master

[blackears]

Started a new PR:
#5813