Midi CC latching

[jpg.wav]

Hello all,

I was curious if anyone has an approach they use for midi cc latching, i.e. preventing a midi cc value from changing until the incoming CC value matches where it was previously left off. Picture a midi controller where the same 8 knobs control different parameters in different isadora scenes. If I leave scene A, use the midi controller in scene B, and then come back, the values of the knobs could be much different than when I left scene A. Using any of these controls then will create a large jump in value that is often undesirable for me. I would like to be able to implement a behavior such that moving those controls when returning to scene A would have no effect until it reaches the value previously set upon leaving that scene, then pick right up from there and function normally. I imagine this would be some combination of gate and comparator actors, but I'm stuck at how I can store and poll the data about the last held CC value when entering a scene. Has anyone else implemented a similar function in one of their patches? Any help or guidance would be much appreciated, as this is something that would make operating my patches live much smoother.

Best,

JP

[Woland]

@jpg-wav

I think what I posted in this thread might be useful: https://community.troikatronix.com/topic/1588/relative-midi-encoders/9?_=1710439233279

[jtsteph]

@jpg-wav

If you are looking to store and poll previous states of your midi controller, you might find @Dusx's and @woland's JSON method useful. It's a very powerful and flexible way of storing midi data for saving, snapshots, comparison etc. The short story of the method is that you create a JSON that stores all the controller states of your midi controller. You can then access or store and recall these states by accessing the JSON. It's very light on system resources and gives you a lot of flexibilty.

[jpg.wav]

@Woland I appreciate your reply but I'm not quite sure it works for my purposes, it seems to still jump around when I try and replace the simulated value change with a control watcher. Perhaps I'm missing something. That thread was an interesting read though, and I learned that 'soft takeover' is the term I was looking for instead of CC latching.

@jtsteph That's a good shout, I've been meaning to dig into those anyway as a means to more easily switch groups of midi controls to different functions within a patch, so this is just another push to take a closer look.

Either way, making this post gave me the extra thinking juice I needed to kludge together a patch of my own that seems to work as I need it to. I've attached a screenshot & user actor below in case anyone else wants to take a look at my solution. v2 would ideally remove the dependence on the enter scene value so that I can use it to stop jumping when reassigning controls within the scene, but I have a good idea on how to do that already.

midi-cc-latch.iua3

[Armando]

I know this is the expensive approach, but this topic is so important that I decided to invest. in a motorized fader machine So I don't have to deal with that.  My 2go machines are Behringer xtouch and it's grandad BCF2000. It might sound stupid but being able to have the faders buttons and encoders all in the right -l;ace at the beginning of every scene is priceless.

[Fred]

@armando this!! But also most controllers that have continuous encoders (not faders as this is not possible, but rotary encoding that has knobs you can just keep turning and show you the level with lights) also have a midi in. This means that you can send the value that you left the scene on back to the unit and go from where you left off. 

[dbini]

@fred

this is why a BCR2000 sometimes works better than a Korg Nano, despite being 20 times the size and weight. 

[Armando]

@fred Sure, for the encoders, but not for the faders. Motors compensate what you describe for infinite rotary faders I love that. The only problem with the Xtouch is that you have to reconfigure it completely before using it with Isadora. Faders spit out data on 2 different controller numbers as they are both on/off buttons on one channel and sliders on another channel. And this confuses the control watcher and even the different MIDI LEARN that exist out there as Isadora user actors. And there is more : the software that Behringer created to reconfigure all the controllers buttons faders and encoders on the Xtouch is pc only. I had to buy Parallel desktop too. The good news is that the Berringer software works well even if you don't buy windows inside Parallel Desktop. Anyone can use it with the non-customizable windows version that comes with Parallel.