Lmms: Adding a new native (sidechain) compressor

[PhysSong]

LMMS currently have various native effects such as EQ, Reverb, Delay, and so on. However, There are no native compressors/limiters in LMMS.
And sidechaining is not easy, since it requires peak controllers(and external sidechain compressors for better quality of output), so it can't be done with just one effect in effect chain. If a native plugin supports it, it would be much easier than now.
Implementing a compressor isn't too hard, but sidechaining will require some major changes in our codebase. It requires audio signals from FX channels and/or individual tracks, which is a functionality not in LMMS yet.
So any ideas about this?

[Umcaruje]

we could implement an audio send plugin/controller that would handle sending the sidechain signal to the compressor.

I really agree with the idea of a native compressor, because it would allow for visual feedback when compressing, I find this very crucial when using other software

[tresf]

visual feedback [...] crucial

Agreed.

could implement an audio send plugin/controller that would handle sending the sidechain signal to the compressor.

It's going to get tricky to handle the various scenarios that the mixer can already do. Perhaps for starters we just make a wizard that assumes 1 channel compresses 1 other channels and links the peak controller to the effect wet/dry (cough #3262, cough). Side-chaining -- although common for mixing can really be exploited for so many other purposes, but reinventing what the mixer already does well should be carefully avoided.

[musikBear]

what are your opinion on the way FLs handles 'sidechaining' ?
They draw a graph for the volume-output in the whole bar
It opens for any creative form of output and are not at all related to what happens in other mixer-channels. -Or is that not proper sidechaining at all?
Beside that- 👍 for a native compressor

[tresf]

It opens for any creative form of output and are not at all related to what happens in other mixer-channels.

Right, this is less of a side-chaining display and more of an "effective effects filter" display. We really need a spectrum analyser for all effects. This is just a place where it becomes pressing because the real-time display is needed extremely helpful for adjusting levels.

I currently do this with an EQ now, but it only shows the after, not the before vs. the after, like most compressor UIs would.

[PhysSong]

2993 seems to be related, but a little bit different. Could we merge two issues into single issue?