skeleton & stubs

crates/engine/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "engine"
+version.workspace = true
+edition.workspace = true
+
+[dependencies]
+params = { workspace = true }

crates/engine/src/lib.rs

@@ -0,0 +1,29 @@
+use params::{ParamId, ParamStore};
+
+pub struct Engine {
+    params: ParamStore,
+    sample_rate: f32,
+}
+
+impl Engine {
+    pub fn new(params: ParamStore, sample_rate: f32) -> Self {
+        Self {
+            params,
+            sample_rate,
+        }
+    }
+
+    pub fn set_sample_rate(&mut self, rate: f32) {
+        self.sample_rate = rate;
+    }
+
+    pub fn process(&mut self, out_l: &mut [f32], out_r: &mut [f32]) {
+        debug_assert_eq!(out_l.len(), out_r.len());
+        out_l.fill(0.0);
+        out_r.fill(0.0);
+
+        let _vol = self.params.get(ParamId::MasterVolume);
+    }
+
+    pub fn midi_event(&mut self, _data: [u8; 3]) {}
+}