Feature request: MPE support #1313
Description
(Or is this better as a discussion?)
I'd like to ask if there are any plans to implement Multichannel Polyphonic Expression in sfizz.
Currently, AFAICS, sfizz responds to all MIDI channels, but the CC and pitch bend states are shared globally -- effectively, there is one channel of response, which happens to accept messages from all channels. I verified this by using SuperCollider with IEM's great VSTPlugin add-on, to round-robin the notes across channels and send a randomized pitch bend with each note, to the same channel. Each PB message affects not only its own, but also any previous ones that hadn't released.
MPE would have independent PB, CC and aftertouch (including poly aftertouch, I think) per channel.
My specific interest is I'm looking for an alternative to Plogue's ancient VST2 sforzando plugin, which is unique in its support for the VST third data byte for detuning. I love generating detuned notes in my software (e.g. here, the comment about just intonation), but wine + yabridge + an old, unsupported plug-in using a deprecated API is... fragile. Sfizz is just about in the pocket, but it doesn't support that third byte, nor does it support MTS, nor MPE. I'd be willing to work with any of those. (Scala files don't meet my needs.)
MPE is growing in popularity, might be good to consider it.