Provide limiters / compressors with controller rack function
So I've had this idea for a while now, and I want it to be implemented into LMMS in some way, and i will explain what it could be used for later.
The feature that I am proposing will take any built-in limiter (eg. Calf Limiter LADSPA), and the limiter will output how much it is reducing the volume of a channel in dB, and put it in the controller rack. I want it to still output to the controller rack even when the limiter is disabled when "bypass" is toggled, so that the limiter isn't altering the volume of the channel it's on. This would decouple the limiter's effect, and the effect of the limiter could be applied to any channel. It would behave similarly to a peak controller, but instead of reducing its value whenever it detects any level of amplitude, it reduces it only when the audio it's tracking passes the point of peaking.
Why would this feature be useful?
Imagine that you applied a limiter to the master channel. This is where the limiter is helpful, because it forces the master channel to never cross the 0 dB threshold, and the audio never clips. The limiter works great for exporting the whole mix, but what if you wanted to export individual stems, while having all of the stems have their volumes reduced, so that when they're all combined, they don't clip? Typically, there are 4 stems (drums, instruments, melody, bass) and it's difficult to make sure that they're all at a volume where they don't clip when combined. But, if you had a limiter that was put on the master, which is the combination of all of the stems, the limiter could reduce the volumes in just the right way that none of them would cross the 0 dB threshold when they're all combined. The limiter could lower the volume of all of the stems by a certain number of decibels for every given moment of time. It's a very niche use case, but very powerful.
But, I'm not sure how it could be implemented without causing problems. If you had the limiter on the master, but it's also controlling the volume of the channels that are sent to the master, then it could cause a feedback loop. But I'd like to see what everyone else thinks about this concept, and how it might be done.