Simultaneous MIDI notes controlling custom data values through Harmonix

[Szlimsedi (Szlimsédi)]

Hello, I am trying to recreate a real life light installation in Unreal Engine. There are around 1500 lights (which are just emissive meshes in the engine) which are controlled by a MIDI file. I have discovered the Harmonix plugin`s MIDI triggers and have set up these outputs in the MetaSoundSource for each channel of the MIDI file

I then get these in my blueprint actor of the instanced static mesh, and use this code to drive their animation.

Each MIDI note corresponds to one light which has the same #. When a new channel is added I just add 127 to the indexlight so the right notes are connecting to the right lights.

Problems are the following: this all messes up when multiple notes are hit at the same time. Also the MIDI note off event won1t hold the info for its midi note if another one is hit meanwhile and therefore it would call the event or the last active one. Which then makes all the lights go on but rarely go off. The MIDI file is the one that is animating the lights irl and therefore full of notes being hit at the same time and overlapping. I can tell that the midi note # I can get output from the MetasoundSource is a single value integer, so it doesn`t account for multiple ones. Is there no other way to do this than to filter each note one by one and output them individually?

I understand this is a new plugin and its already wonderful, and Im asking a lot, so I might have just run into limitations. However I am also not too versed in programming nor metasounds so maybe someone could offer a solution which would avoid making 1500 graph outputs and custom events.

[Albertros423]

So, long story short ‘the midi note trigger’ is not polyphonic and will only pick out the lowest note if you have several playing at the same time, this is a limitation of the node, fortunately though, you don’t need to use it at all in this scenario, just promote the Midi Stream to an output and then use the Metasound Output Watch subsystem to get this output from the metasound, when receiving the midistream in BP using the output watch subsystem (and the ‘get midi note info’ method) you’ll get all the notes in the stream and you can use them for polyphonic triggers.

[Szlimsedi (Szlimsédi)]

Promoted the midi stream to an output but all I can access from it in the blueprint is the index of tracks and the tempo via the timestamp thing, don`t see a way to get the information about notes being played let alone which one.

[Albertros423]