Keijiro Takahashi is an amazing developer who works for unity and has been releasing a lot of stuff on github for controlling MIDI input and output with unity
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Basically what this means is that you can create a 'game' or something that has your MIDI input dictating some control within the 'game' and you could have a unique and complex MIDI output based on something happening within the 'game'
You could make sequencers that use game physics to influence the output for example, or very complex automation that uses game physics as well
I'm going to try to make a few apps for this including a sequencer, a semi-automated filter control for knob controllers, and a semi-automated x-y filter for a mouse
If anything comes to fruition I'll post it on here, but I also thought it'd be good to share this with you guys in case anyone is interested in making their own apps with this. It seems like hardly anyone knows that you can do this with Unity, I haven't seen anyone else put anything out for using Unity with MIDI, aside from stuff on Keijiro's github.