Started working on MIDI processing

src/nodes/note_buffer.rs

@@ -0,0 +1,40 @@
+// Copyright (c) 2022 Weird Constructor <weirdconstructor@gmail.com>
+// This file is a part of HexoDSP. Released under GPL-3.0-or-later.
+// See README.md and COPYING for details.
+
+use crate::dsp::MAX_BLOCK_SIZE;
+use crate::util::Smoother;
+
+#[derive(Debug, Clone, Copy)]
+pub struct ChannelState {
+    vel: f32,
+    pitch: u8,
+    gate: u8,
+}
+
+pub struct NoteBuffer {
+    interleaved_chans: Vec<ChannelState>,
+    buf_idx: usize,
+}
+
+impl NoteBuffer {
+    pub fn new() -> Self {
+        Self {
+            interleaved_chans: vec![ChannelState::new(); 16 * MAX_BLOCK_SIZE],
+            buf_idx: 15,
+        }
+    }
+
+    #[inline]
+    pub fn step(&mut self) {
+        let cur = self.buf_idx;
+        let next = (self.buf_idx + 1) % 16;
+        self.interleaved_chans.copy_within((cur * 16)..((cur + 1) * 16), next * 16);
+    }
+
+//    pub fn play_velocity(&mut self, channel: u8, vel: f32) {
+//        let mut vel = &mut self.velocity[channel % 16];
+//        vel.set(vel.current(), vel);
+//    }
+}
+