Oh, and all the VST binaries don't seem to build, that would have to be sorted out also.

So, I got to experiment with this properly. I have a question: normally, when recording and jamming, we interpret the midi channel to correspond to the instrument that is being played. But now you input whatever MIDI notes have arrived at the current cursor position. Little bit confusingly, the player still respects the channel instrument as the instrument being played, so even if you input a note on track corresponding to instrument Foo, but the channel of the MIDI message corresponds to instrument Bar, the player will play instrument Bar. I guess at least we should at least somehow trigger the right instrument to not confuse the user?

In your use case, I think you intentionally do not want to respect the channel information of the MIDI message, right? So you want to have a MIDI keyboard near by, and place the cursor where-ever, and input a note at that position, so it's almost similar as pressing a note on keyboard?

Merged, thank you for your contribution!

Just a little heads up that I completely reworked the MIDI input logic so that the MIDI events work just as an alternative to keyboard. Namely, if the MIDI input mode is turned on, all MIDI events are sent to GUI and the GUI is free to deal with them as it pleases. If not, they are sent directly to the player.

The GUI ignores the channel of the MIDI note on event, and now it works like the keyboard: if a track is selected, then it inputs a note to the track. Otherwise, it triggers the currently selected instrument.

Now, this did remove the "chord" input support i.e. inputting nodes on multiple tracks. But I remember you indicated that it would need anyway rethinking a bit, especially for the velocity. I am also still thinking of the note velocity: if it should be a deeper rethinking of the entire sointu internals (poking things even on the synth side), and not just a fancy way to input notes on the GUI side.