From 3f3077c24740ea86b5cecefb6c6ef0d4a0fabe80 Mon Sep 17 00:00:00 2001
From: Russell McClellan <russell.mcclellan@gmail.com>
Date: Mon, 10 Feb 2025 23:54:56 -0500
Subject: [PATCH] make poly realtime-safe (#35)

---
 Cargo.lock             | 7 +++++++
 rust/poly/Cargo.toml   | 1 +
 rust/poly/src/state.rs | 8 +++++---
 3 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 1c32f86..3152412 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "arrayvec"
+version = "0.7.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7c02d123df017efcdfbd739ef81735b36c5ba83ec3c59c80a9d7ecc718f92e50"
+
 [[package]]
 name = "assert_approx_eq"
 version = "1.1.0"
@@ -232,6 +238,7 @@ dependencies = [
 name = "conformal_poly"
 version = "0.0.0"
 dependencies = [
+ "arrayvec",
  "conformal_component",
 ]
 
diff --git a/rust/poly/Cargo.toml b/rust/poly/Cargo.toml
index 68f38cd..b52e385 100644
--- a/rust/poly/Cargo.toml
+++ b/rust/poly/Cargo.toml
@@ -13,3 +13,4 @@ workspace = true
 
 [dependencies]
 conformal_component = { version = "0.0.0", path = "../component" }
+arrayvec = "0.7.6"
diff --git a/rust/poly/src/state.rs b/rust/poly/src/state.rs
index 85b285a..36e5e17 100644
--- a/rust/poly/src/state.rs
+++ b/rust/poly/src/state.rs
@@ -52,11 +52,13 @@ pub struct Voice {
     expression: NoteExpressionState,
 }
 
+const MAX_VOICES: usize = 32;
+
 #[derive(Clone, Debug, PartialEq)]
 pub struct State {
-    voices: Vec<Voice>,
+    voices: arrayvec::ArrayVec<Voice, MAX_VOICES>,
 
-    voices_compress_order_scratch: Vec<(usize, usize)>,
+    voices_compress_order_scratch: arrayvec::ArrayVec<(usize, usize), MAX_VOICES>,
 }
 
 struct EventStreamStep {
@@ -172,7 +174,7 @@ impl State {
                     expression: NoteExpressionState::default(),
                 })
                 .collect(),
-            voices_compress_order_scratch: Vec::with_capacity(max_voices),
+            voices_compress_order_scratch: Default::default(),
         }
     }