The closest thing I’ve seen before this thread is a QT/C++ app that did piano roll over OSC by a user named Re.Dread (?) I spent the last 30 minutes looking for the topic where his tool was discussed, with screenshots, and failed. Deleted? I did find the GitHub repo: [https://github.com/dmin7/Qtroll ] The protoype was named re.dread.Qtroll.xrnx
Oh yeah, and Mini Roll: