adding controls for BPM operations (so we can create shortcuts)

[FrankwaP]

Hi!

My objective is to accelerate the track preparations by using keyboard shortcuts.

The basics are:

• adjusting the BPM (x1/2, …, x2)
• translating the beatgrid
• locking/unlocking the BPM

So far it's only possible to create shortcuts for "translating the beatgrid", using beats_translate_earlier, beats_translate_later, and beats_translate_curpos controls.

This PR is about creating controls for "adjusting the BPM (x1/2, …, x2)", so it's possible to create shortcuts.
BTW I've found this old post asking for such feature: https://mixxx.discourse.group/t/double-halve-bpm-with-keyboard/13333

Side note:
I play music with breakbeats like dnb, jungle, breakcore… and I think these are among the trickiest BPM to guess.
Yet, I only use x3/2 and x2 BPM adjustment and I'm wondering if the other adjustments are actually useful at all. Were there requests for these or is it a YAGNI case?

[JoergAtGithub]

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[mxmilkiib]

Hi! Keyboard shortcuts for this would be handy. I made a PR recently for doing it by MIDI #12934. I guess they shouldn't conflict, though possibly there might be ways to make them align, in text used maybe or such. Or maybe at a deeper level. (I haven't checked your code yet, just browsing the latest activity of the project).

Big up bass n breaks n fast paces!

Edit: yeah, looks like they're is a bit of a clash, but it can be made to work. I'll leave saying what to someone who knows the project better, I'm at the newb end of things here.

[FrankwaP]

@mxmilkiib Well it's definitely a clash if not a complete duplicate :-p

My bad as yours is 4 days earlier and I actually saw it… but since I hadn't put my nose into the code at that time, that did not make much sense to me.

I definitely looks like the best choice is to cancel my PR.

[FrankwaP]

Keyboard shortcuts for this would be handy.

In your case (using the semantic of your PR), you can add such lines into a custom keyboard mapping:

[Channel1]
beats_set_halve Shift+Ctrl+F1
...
beats_set_double Shift+Ctrl+F6

[Channel2]
beats_set_halve Shift+Ctrl+F7
...
beats_set_double Shift+Ctrl+F12

Big up bass n breaks n fast paces!

Big up the drums packed 174 BPM tracks that are detected as 116 BPM :-D

[mxmilkiib]

Stars yeah! I sat down to DJ at 160 after finishing a previous PR, and every second track was like 96, 106, or 120, n sod reaching for the mouse every time.

Just need to map it all to my Launchpad now.. (keep distracting my AuDHD self though from my evening flow, like, got a new qmk keyboard start of the week, saw DJ Shadow weds, Randall last night (support was better though). Anyhow! 🤜🤘)

Maybe a sensible ordered set of double/triple modifier hotkeys could cover all fractions for all decks for a potential addition to the defaults?