The "piano roll timeline triggering" was my first option but it looks way more difficult to do (for accelerations, speeds, direction, etc)
So if I add 8+ more MIDI tracks handling my Arduinos I think my 2008 macbook pro will explode.
And it also means that I would need to have my Arduinos constantly plugged in my computer.
Also, I don't understand what you mean by "drifting out of sync due to temperature variations". Arduinos have an internal clock right? So why would the timings in my code be messed up?
I begin to get lost with all the possibilities to achieve that, and I don't have so much time to complete this project and I really don't know how to separate the wheat from the chaff to be the most efficient possible
Keep it simple and don't add too many features at one go. Start simple and do as much as you can in the time you have.
At the moment I'm guessing that each of the Arduino machines will have it's own fixed sequence of actions which just needs to be started and perhaps stopped at specific points in the playback. If so then you can just use a different "note" for each machine and your trigger track will then contain long "notes" to cover the times when each machine is to be active. The code needed to receive MIDI commands is not trivial but there are many examples and decent libraries available
I'd probably start by making a single Arduino "machine" that just receives MIDI note on/note off commands (a specific note on a specific channel) and switches an LED on and off. Once you have that working you're almost there.
(and the project is interesting enough that you'll probably have plenty of help )
It shouldn't be nearly as complicated at the Reaper end as that video suggests. But since I've never actually done it I'd better test my theories myself before I tell you how easy it is;). Give me a few days, I don't have a lot of spare time just now.Steve
That's the only example I found of Reaper MIDI track sending informations to Arduino...