Macro synfx_dsp_jit::stateful_dsp_node_type

macro_rules! stateful_dsp_node_type {
    ($node_type: ident, $struct_type: ident =>
     $func_name: ident $jit_name: literal $signature: literal
     doc $doc: literal
     inputs $($idx: literal $inp: literal)*
     outputs $($idxo: literal $out: literal)*) => { ... };
}

This macro can help you defining new stateful DSP nodes.

 use synfx_dsp_jit::*;

 struct MyDSPNode {
     value: f64,
 }

 impl MyDSPNode {
     fn reset(&mut self, _state: &mut DSPState) {
         *self = Self::default();
     }
 }

 impl Default for MyDSPNode {
     fn default() -> Self {
         Self { value: 0.0 }
     }
 }

 extern "C" fn process_my_dsp_node(my_state: *mut MyDSPNode) -> f64 {
     let mut my_state = unsafe { &mut *my_state };
     my_state.value += 1.0;
     my_state.value
 }

 // DIYNodeType is the type that is newly defined here, that one you
 // pass to DSPNodeTypeLibrary::add
 synfx_dsp_jit::stateful_dsp_node_type! {
     DIYNodeType, MyDSPNode => process_my_dsp_node "my_dsp" "Sr"
     doc
     "This is a simple counter. It counts by increments of 1.0 everytime it's called."
     inputs
     outputs
     0 "sum"
 }

 // Then use the type by adding it:
 fn make_library() -> DSPNodeTypeLibrary {
     let mut lib = DSPNodeTypeLibrary::new();
     lib.add(DIYNodeType::new_ref());
     lib
 }

You might’ve guessed, process_my_dsp_node is the function identifier in the Rust code. The "my_dsp" is the name you can use to refer to this in crate::ASTNode::Call: ASTNode::Call("my_dsp".to_string(), 1, ...). Attention: Make sure to provide unique state IDs here!

The "Sr" is a string that specifies the signature of the function. Following characters are available:

• “v” - A floating point value
• “D” - The global crate::DSPState pointer
• “S” - The node specific state pointer (MyDSPNode)
• “M” - A pointer to the multi return value array, of type *mut [f64; 5]. These can be accessed by the variables “%1” to “%5” after the call.
• “r” - Must be specified as last one, defines that this function returns something.