Unexpected Behaviour of vuo.list.process

Attached screenshot shows that “DMX output” stopped firing events to “Process Item”. This happens after unplugging, e.g. “Get Item From List” (left down corner) form “Blue”. Why is this happening? Am I not getting something about the event queue?

Restarting the composition “resolves” the issue.

Thanks in advance!

I see the point now: using a MIDI-controller (fader) as input produces up to 500 frames per sec. Piping it through vuo.list.process causes massive delay (up to 10 sec ifF the data is rendered to the screen) => so I was thinking its unexpected behaviour. Setting Event Throttling to “drop” in the process nodes output(s?) helps out.


Yes, events from MIDI devices (and other input sources) can come in much faster than the video framerate, and they can get queued up and take a long time for that queue to drain.

Rather than changing Process List’s output ports to Drop Events (which could break things, since Process List expects all the events it fires out its Process Item port to be returned through its Processed Item port), I’d recommend either changing Receive MIDI Events’s ports to Drop Events, or inserting a Hold Value between Receive MIDI Events and Process List, and attaching a slower event stream to push the data through the Hold Value node (such as a Render Scene/Layers to Window node’s Requested Frame output).

(Also, it looks like the attachment didn’t make it. If you still have questions, please attach the composition and we can provide some more specific feedback.)