Comment by neobrain
That problem is solved by the subsecond crate (an offspring of the Dioxus UI framework), demo here: https://youtu.be/Kl90J5RmPxY?t=1288
It's not integrated in Nannou specifically, but they're showing off Bevy and ratatui in that demo, both very popular frameworks in the Rust world. (In fact, Nannou is in the process of being rebuilt on top of Bevy.)
I don’t know if something is wrong with my mental model, but it seems weird to me that it would take hundreds of milliseconds to patch a function pointer.