Deere: add per-channel mute buttons next to gain knobs

[mxmilkiib]

adds mute button next to gain knob in all mixer layouts (2-deck and 4-deck). button uses existing EQKillButton styling and is controlled by show_eq_kill_buttons setting. uses [Channel],mute control for channel muting.

closes #15623

[mxmilkiib]

the positioning for 2 decks might need a change
given the alternate channel strip layouts because of the different height available in either count of decks
with the gain above in 4 deck form, and to the side in 2 deck form

edit: is this the kind of thing that should be rebased to 2.5, or is that just for bugfixes?

edit: the pfl could go to the side of the fx menu, the deck vus go a bit nearer the rest, then the main vu can go all the way to the bottom(?)

[ronso0]

Why is this needed for mixing? Why is the Vol fader not sufficient?
Btw I'm not aware of a (mainstream) mixer or controller with a channel mute button.

[mxmilkiib]

it makes the process of performing the action easy;

there's less to go wrong / it's quicker,
performing a full track mute for however many fractions of a beat

(hmm, right-click can be momentary)

and, most likely, depending on the DJ, it sounds different

just had nasal surgery, shall see how my spoons go

[daschuer]

For me the gain button is actually only decoration. Replay-Gain works nice and the EQ is sufficient. I have no need for more deco.

I can imagine rare use case where one is using Gain along with EQs and also want a kill-all button, but this is likely a cumbersome workaround for a certain effect they want to achieve see: #6918.
Maybe a knob widget with an integrated kill feature can be used for this to save GUI space and all other knobs in the mixer region.

But maybe we should redirect our energy. We may revive the alternative EQ model discussion and Stem controls discussion. There might be a new easy accessible way using a 4 knob set up, that covers the 80 % of common isolator stem use cases. This would be a mayor benefit on my old controller.

We have also recently added the "Tremolo" effect which can also do the described "Transformer" effect. Maybe we can think about a manual mode for it. Does it work with effect mappings?

[ronso0]

For me the gain button is actually only decoration.

Well, you need to adjust the gain, then Update ReplayGain from deck gain.
And it's helpful for checking if GUI and controller knobs are in sync.

[ronso0]

Maybe a knob widget with an integrated kill feature can be used for this to save GUI space and all other knobs in the mixer region.

Jup, like to have that as well. If we want to save GUI space with this we'd need a kill/mute indicator as well. Would be cool to have this integrated in the knob widget.
Right-click would be handy as it is instant (compared to double-click where the widget waits for [double-click period] which can be as long as 500 ms.
But we decided to 'reset' on double-click.
There could be an option in Preferences -> Interface to select the the right-/double-click behavior.

[ronso0]

Returning to this, I think we should not merge it. Mainly because there's a close to zero demand (this never came up before this PR) and there is no hardware DJ mixer I know of that has this control.
Also, if we still aim to keep all official skins somewhat equal in terms of available features, it's cumbersome to integrate in the settled, compact layouts of LateNight and Tango.
I suggest to keep merge it to your fork instead.

@daschuer any objections?

[mxmilkiib]

i would say that channel mute buttons are not uncommon in audio spheres

[mxmilkiib]

I didn't know, but there's now the silent cue feature about https://youtu.be/wIwBw_xmi3M?t=193 which is a channel mute plus ability to unmute on the next hotcue press

[ronso0]

Sure that's interesting! we can add a Silent Cue button when Mixxx has the feature itself. It's a feature made for turntableists and atm you can already code it rather easily in a mapping, ie. have a spare button/LED.
Same for fader start btw.

Still objecting to merge this for reasons stated above.

[mxmilkiib]

it's an action popular enough to already have an existing control in Mixxx

I would hazard a guess that you have seen DJs slamming faders down and up to make all sorts of new sounds; is the result of that behavior not popular enough?

[ronso0]

Of course I saw and see this, especially by former vinyl DJs, and I do it myself. And long ago I also suggested they use the crossfader to do these cuts as it would be sharper.
But hard cuts is not what it's about (for them, and me), it's about that subtle Vol fade that you get no matter how fast you pull the fader up or down.

[daschuer]

Had a brief look to the video. The term "silent cue" is a bit misleading. I would call it "unmute by cue". I is an interesting feature.
Let's consider it is implemented with a mapping, I think Mixxx leaks a visual feedback for such mute state.
The controller has also no dedicated button for it.

So I suggest to "mute" this PR here until we have a demand and a good plan for this turntableist feature.

[ronso0]

I'll mark it draft so it can b found with the "Open" filter

[mxmilkiib]

without pixel peeped spacing finishes

[mxmilkiib]

I guess preferences for the attack/release speed of channel/EQ mutes is a serious consideration

but I don't get what the blocker actually is here

because you don't like the "sound" of a digital channel mute? obviously a subjective take, and a thing that can be programmed for (and already is, to avoid pops)

the proliferation of digital mixers used by performers the world over with some portion who must use channel mute buttons as part of live creation means it's an acceptable aesthetic, no?

plus there's hundreds of things that have been added to Mixxx where it would be arguable as to levels of public desire

does channel mutes on an audio mixer have such questionable worth?

but instead, the bar is the addition of a feature that is not a widely known thing, a new idea here, not programmed and in builds for years, n not an immediate solution for a needed visual indicator, does?

if channel mutes haven't been in skins thus far;

have PRs without full skin support never been accepted? will the habitual users of other skins get too upset?

is it the belief that no-one can add it to all themes? are they so apparently painted into such a corner?

[ronso0]

This is not about what sounds I like or not. I tried to explain my reason to reject this (the current state of this PR) in my comment above.
Mainly: if we add a new GUI control, especially mixer control (which is considered helpful as it allows more mixing techniques) -- all skins should get it.
I'm not aware of a mixing helper to is exclusive to one particular skin.
LateNight: default skin, deserves more care than let's say Tango, layout is accessible and settled, I see no space for an extra Mute button (with reasonable size, in a reasonable place), ie. showing the Gain toggle together with the EQ kill toggles requires either to shift the Vol colum (-> empty space that expands the mixer) or squeezing the Vol fader (-> usability regression)
-- tradeoff: I could live with an indicator (a bit like but slightly larger than the Kill indicators when Kill buttons are hidden) so we have at least proper feedback when mute is toggled with the keyboard.
Tango: not sure where it would fit, we could put it next to or below the Gain knob (the former means knob and fader are not in line anymore, the latter means we'd need to squeeze the Vol fader -> don't like)
Shade: no prob, just mimic the Kill button pos

---

Question remains: if we figure proper skin implementations -- how's gonna do it? ie. add the feature to LateNight, Tango & Shade?
It won't be me, I have spent hundreds if not thousands of hours on Tango & LateNight already, am not motivated to push my other work for a feature I'm personally not convinced there's a demand for.
You? I have serious doubts tbh, looking back at how long various PRs of yours sat & waited until reviewers got a response.

Conclusion (just me, and I'm okay with being overruled), for the sake of skins' feature equality and less workload for developers, and given that main will soon be 2.7-beta: either do it for all skins, or drop it.

@daschuer What's your opinion on this?

FWIW this is an entirely different story if we add a radio skin, or one that has a more studio-like mixer layout.