libfaust (LLVM) support?

[YPares]

Hi! I'm working on a plugin that loads DSPs using the llvm backend ( https://github.com/YPares/nih-faust-jit ). I knew about rust-faust from the start, but given my specific needs (and also as a learning process) I ended up rewriting an ad-hoc wrapper for libfaust myself (based on bindgen), both for loading DSPs and creating their GUIs.
Now that I have a better idea of how to use libfaust as part of a Rust project, would you be interested in a PR to rust-faust to add support for the llvm backend?

[obsoleszenz]

I think it would be nice! Also for hot reloading this could be quite cool. I myself stopped using faust-state but having faust-llvm parallel to faust-build and a maybe a layer on top if needed could be nice.

Do you have an idea how this could be integrated or how this could look like?

[YPares]

@obsoleszenz faust-states is for representing in Rust datastructures the internal state of a DSP, right?

I think implementing faust-types with llvm-based DSPs should be the way to go, and it shouldn't be too hard to it for any dsp (the abstract faust class). The wrappers in my project are a bit higher-level for now (because the fewer functions to bind, the easier). The major question is the build. I link with a system-installed libfaust, maybe building it as part of a new faust-llvm crate might be simpler and more OS-agnostic.

[obsoleszenz]

Hmmm i think for building it would be nice to statically link against faust + llvm. But not exactly sure how to do it.

[sletz]

faust-llvm @YPares do you mean this system level crate that would embed the libfaust binaries themselves ?

[YPares]

@sletz That's what I meant, yes. libfaust is not super heavy, so it may be worth it, in order to make the build process simpler (at least on some OSs with no decent package managers...).

[YPares]

I've split the faust llvm logic on https://github.com/YPares/nih-faust-jit in a separate faust_jit crate (which would be roughly equivalent to that sys crate we were talking about, though the API isn't changed yet to be more aligned with what rust-faust expects). But that makes it reusable already.
Drawing the DSP widgets with egui is also done by a separate faust_jit_egui crate.