WIP: Convert CV2 <-> CV1

midi2/src/channel_voice2/note_on.rs

@@ -30,6 +30,59 @@ struct NoteOn {
     attribute: Option<Attribute>,
 }
 
+/// Converts a CV2 Note On message to CV1 Note On message,
+/// storing the result in a pre-instantiated CV1 Note On.
+///
+/// Note: Due to 0 velocity Note On messages being considered
+/// a Note Off in CV1 but not in CV2, a 0 velocity CV2 message
+/// will be converted to a 1 velocity CV1 message.
+#[cfg(feature = "channel-voice1")]
+impl<
+        A: crate::buffer::Buffer<Unit = u32>,
+        B: crate::buffer::Buffer<Unit = u32> + crate::buffer::BufferMut,
+    > Into<crate::channel_voice1::NoteOn<B>> for (NoteOn<A>, crate::channel_voice1::NoteOn<B>)
+{
+    fn into(self) -> crate::channel_voice1::NoteOn<B> {
+        use crate::traits::{Channeled, Grouped};
+
+        let (src, mut dest) = self;
+        dest.set_group(src.group());
+        dest.set_channel(src.channel());
+        dest.set_note_number(src.note_number());
+        match src.velocity() {
+            // Since 0 velocity doesn't trigger a note off in CV2 like in CV1,
+            // we need to convert 0 velocity in CV2 to 1 velocity in CV1.
+            // See MIDI 2.0 spec 7.4.2: MIDI 2.0 Note On Message -> Velocity
+            // for details.
+            0 => dest.set_velocity(u7::new(0x01)),
+            _ => dest.set_velocity(u7::new((src.velocity() >> 9) as u8)),
+        }
+        dest
+    }
+}
+
+/// Converts a CV2 Note On message to a CV1 Note On message.
+/// This is only infallible for resizable buffers.
+/// For fixed size buffers, see the Into impl for (CV2, CV1).
+///
+/// Note: Due to 0 velocity Note On messages being considered
+/// a Note Off in CV1 but not in CV2, a 0 velocity CV2 message
+/// will be converted to a 1 velocity CV1 message.
+#[cfg(feature = "channel-voice1")]
+impl<
+        A: crate::buffer::Buffer<Unit = u32>,
+        B: crate::buffer::Buffer<Unit = u32>
+            + crate::buffer::BufferMut
+            + crate::buffer::BufferDefault
+            + crate::buffer::BufferResize,
+    > Into<crate::channel_voice1::NoteOn<B>> for NoteOn<A>
+{
+    fn into(self) -> crate::channel_voice1::NoteOn<B> {
+        let dest = crate::channel_voice1::NoteOn::<B>::new();
+        (self, dest).into()
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -96,4 +149,104 @@ mod tests {
             Some(Attribute::Pitch7_9(Fixed7_9::from_bits(0b1110100110001010))),
         );
     }
+
+    #[test]
+    fn into_midi_1() {
+        use crate::channel_voice1;
+        use crate::traits::{Channeled, Grouped};
+        use std::vec::Vec;
+
+        let mut message2 = NoteOn::<[u32; 4]>::new();
+        message2.set_group(u4::new(0x8));
+        message2.set_channel(u4::new(0x8));
+        message2.set_note_number(u7::new(0x5E));
+        message2.set_velocity(0x8000);
+
+        assert_eq!(message2, NoteOn([0x4898_5E00, 0x8000_0000, 0x0, 0x0]),);
+
+        let mut message1 = channel_voice1::NoteOn::<Vec<u32>>::new();
+        message1.set_group(u4::new(0x8));
+        message1.set_channel(u4::new(0x8));
+        message1.set_note_number(u7::new(0x5E));
+        message1.set_velocity(u7::new(0x40));
+
+        let message21: channel_voice1::NoteOn<Vec<u32>> = message2.into();
+
+        assert_eq!(message21, message1);
+    }
+
+    #[test]
+    fn into_midi_1_zero_velocity() {
+        use crate::channel_voice1;
+        use crate::traits::{Channeled, Grouped};
+        use std::vec::Vec;
+
+        let mut message2 = NoteOn::<[u32; 4]>::new();
+        message2.set_group(u4::new(0x8));
+        message2.set_channel(u4::new(0x8));
+        message2.set_note_number(u7::new(0x5E));
+        message2.set_velocity(0x0000);
+
+        assert_eq!(message2, NoteOn([0x4898_5E00, 0x0000_0000, 0x0, 0x0]),);
+
+        let mut message1 = channel_voice1::NoteOn::<Vec<u32>>::new();
+        message1.set_group(u4::new(0x8));
+        message1.set_channel(u4::new(0x8));
+        message1.set_note_number(u7::new(0x5E));
+        message1.set_velocity(u7::new(0x01));
+
+        let message21: channel_voice1::NoteOn<Vec<u32>> = message2.into();
+
+        assert_eq!(message21, message1);
+    }
+
+    #[test]
+    fn into_midi_1_with_dest() {
+        use crate::channel_voice1;
+        use crate::traits::{Channeled, Grouped};
+
+        let mut message2 = NoteOn::<[u32; 4]>::new();
+        message2.set_group(u4::new(0x8));
+        message2.set_channel(u4::new(0x8));
+        message2.set_note_number(u7::new(0x5E));
+        message2.set_velocity(0x8000);
+
+        assert_eq!(message2, NoteOn([0x4898_5E00, 0x8000_0000, 0x0, 0x0]),);
+
+        let mut message1 = channel_voice1::NoteOn::<[u32; 4]>::new();
+        message1.set_group(u4::new(0x8));
+        message1.set_channel(u4::new(0x8));
+        message1.set_note_number(u7::new(0x5E));
+        message1.set_velocity(u7::new(0x40));
+
+        let message21 = channel_voice1::NoteOn::<[u32; 4]>::new();
+        let message21: channel_voice1::NoteOn<[u32; 4]> = (message2, message21).into();
+
+        assert_eq!(message21, message1);
+    }
+
+    #[test]
+    fn into_midi_1_zero_velocity_with_dest() {
+        use crate::channel_voice1;
+        use crate::traits::{Channeled, Grouped};
+
+        let mut message2 = NoteOn::<[u32; 4]>::new();
+        message2.set_group(u4::new(0x8));
+        message2.set_channel(u4::new(0x8));
+        message2.set_note_number(u7::new(0x5E));
+        message2.set_velocity(0x0000);
+
+        assert_eq!(message2, NoteOn([0x4898_5E00, 0x0000_0000, 0x0, 0x0]),);
+
+        let mut message1 = channel_voice1::NoteOn::<[u32; 4]>::new();
+        message1.set_group(u4::new(0x8));
+        message1.set_channel(u4::new(0x8));
+        message1.set_note_number(u7::new(0x5E));
+        message1.set_velocity(u7::new(0x01));
+
+        let message21 = channel_voice1::NoteOn::<[u32; 4]>::new();
+        let message21: channel_voice1::NoteOn<[u32; 4]> = (message2, message21).into();
+
+        assert_eq!(message21, message1);
+    }
 }