break up into crates again

engine/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name    = "tek_engine"
+edition = { workspace = true }
+version = { workspace = true }
+
+[lib]
+path = "engine.rs"
+
+[target.'cfg(target_os = "linux")']
+rustflags = ["-C", "link-arg=-fuse-ld=mold"]
+
+[dependencies]
+atomic_float = { workspace = true }
+jack         = { workspace = true }
+midly        = { workspace = true }
+tengri       = { workspace = true }
+
+[dev-dependencies]
+proptest        = { workspace = true }
+proptest-derive = { workspace = true }
+
+[features]

engine/engine.rs

@@ -0,0 +1,155 @@
+mod engine_deps; pub use self::engine_deps::*;
+mod time; pub use self::time::*;
+mod note; pub use self::note::*;
+mod jack; pub use self::jack::*;
+mod midi; pub use self::midi::*;
+
+//pub trait MaybeHas<T>: Send + Sync {
+    //fn get (&self) -> Option<&T>;
+//}
+
+//impl<T, U: Has<Option<T>>> MaybeHas<T> for U {
+    //fn get (&self) -> Option<&T> {
+        //Has::<Option<T>>::get(self).as_ref()
+    //}
+//}
+
+pub trait HasN<T>: Send + Sync {
+    fn get_nth     (&self,     key: usize) -> &T;
+    fn get_nth_mut (&mut self, key: usize) -> &mut T;
+}
+
+pub trait Gettable<T> {
+    /// Returns current value
+    fn get (&self) -> T;
+}
+
+pub trait Mutable<T>: Gettable<T> {
+    /// Sets new value, returns old
+    fn set (&mut self, value: T) -> T;
+}
+
+pub trait InteriorMutable<T>: Gettable<T> {
+    /// Sets new value, returns old
+    fn set (&self, value: T) -> T;
+}
+
+impl Gettable<bool> for AtomicBool {
+    fn get (&self) -> bool { self.load(Relaxed) }
+}
+
+impl InteriorMutable<bool> for AtomicBool {
+    fn set (&self, value: bool) -> bool { self.swap(value, Relaxed) }
+}
+
+impl Gettable<usize> for AtomicUsize {
+    fn get (&self) -> usize { self.load(Relaxed) }
+}
+
+impl InteriorMutable<usize> for AtomicUsize {
+    fn set (&self, value: usize) -> usize { self.swap(value, Relaxed) }
+}
+
+#[cfg(test)] #[test] fn test_time () -> Usually<()> {
+    // TODO!
+    Ok(())
+}
+
+#[cfg(test)] #[test] fn test_midi_range () {
+    let model = MidiRangeModel::from((1, false));
+
+    let _ = model.get_time_len();
+    let _ = model.get_time_zoom();
+    let _ = model.get_time_lock();
+    let _ = model.get_time_start();
+    let _ = model.get_time_axis();
+    let _ = model.get_time_end();
+
+    let _ = model.get_note_lo();
+    let _ = model.get_note_axis();
+    let _ = model.get_note_hi();
+}
+
+//macro_rules! impl_port {
+    //($Name:ident : $Spec:ident -> $Pair:ident |$jack:ident, $name:ident|$port:expr) => {
+        //#[derive(Debug)] pub struct $Name {
+            ///// Handle to JACK client, for receiving reconnect events.
+            //jack: Jack<'static>,
+            ///// Port name
+            //name: Arc<str>,
+            ///// Port handle.
+            //port: Port<$Spec>,
+            ///// List of ports to connect to.
+            //conn: Vec<PortConnect>
+        //}
+        //impl AsRef<Port<$Spec>> for $Name {
+            //fn as_ref (&self) -> &Port<$Spec> { &self.port }
+        //}
+        //impl $Name {
+            //pub fn new ($jack: &Jack, name: impl AsRef<str>, connect: &[PortConnect])
+                //-> Usually<Self>
+            //{
+                //let $name = name.as_ref();
+                //let jack = $jack.clone();
+                //let port = $port?;
+                //let name = $name.into();
+                //let conn = connect.to_vec();
+                //let port = Self { jack, port, name, conn };
+                //port.connect_to_matching()?;
+                //Ok(port)
+            //}
+            //pub fn name (&self) -> &Arc<str> { &self.name }
+            //pub fn port (&self) -> &Port<$Spec> { &self.port }
+            //pub fn port_mut (&mut self) -> &mut Port<$Spec> { &mut self.port }
+            //pub fn into_port (self) -> Port<$Spec> { self.port }
+            //pub fn close (self) -> Usually<()> {
+                //let Self { jack, port, .. } = self;
+                //Ok(jack.with_client(|client|client.unregister_port(port))?)
+            //}
+        //}
+        //impl HasJack<'static> for $Name {
+            //fn jack (&self) -> &'static Jack<'static> { &self.jack } 
+        //}
+        //impl JackPort<'static> for $Name {
+            //type Port = $Spec;
+            //type Pair = $Pair;
+            //fn port (&self) -> &Port<$Spec> { &self.port }
+        //}
+        //impl ConnectTo<'static, &str> for $Name {
+            //fn connect_to (&self, to: &str) -> Usually<PortConnectStatus> {
+                //self.with_client(|c|if let Some(ref port) = c.port_by_name(to.as_ref()) {
+                    //self.connect_to(port)
+                //} else {
+                    //Ok(Missing)
+                //})
+            //}
+        //}
+        //impl ConnectTo<'static, &Port<Unowned>> for $Name {
+            //fn connect_to (&self, port: &Port<Unowned>) -> Usually<PortConnectStatus> {
+                //self.with_client(|c|Ok(if let Ok(_) = c.connect_ports(&self.port, port) {
+                    //Connected
+                //} else if let Ok(_) = c.connect_ports(port, &self.port) {
+                    //Connected
+                //} else {
+                    //Mismatch
+                //}))
+            //}
+        //}
+        //impl ConnectTo<'static, &Port<$Pair>> for $Name {
+            //fn connect_to (&self, port: &Port<$Pair>) -> Usually<PortConnectStatus> {
+                //self.with_client(|c|Ok(if let Ok(_) = c.connect_ports(&self.port, port) {
+                    //Connected
+                //} else if let Ok(_) = c.connect_ports(port, &self.port) {
+                    //Connected
+                //} else {
+                    //Mismatch
+                //}))
+            //}
+        //}
+        //impl ConnectAuto<'static> for $Name {
+            //fn connections (&self) -> &[PortConnect] {
+                //&self.conn
+            //}
+        //}
+    //};
+//}

engine/engine_deps.rs

@@ -0,0 +1,11 @@
+pub use ::tengri;
+pub(crate) use ::{
+    tengri::{Usually, from},
+    atomic_float::AtomicF64,
+    std::{
+        cmp::Ord,
+        fmt::Debug,
+        ops::{Add, Sub, Mul, Div, Rem},
+        sync::{Arc, RwLock, atomic::{AtomicBool, AtomicUsize, Ordering::Relaxed}},
+    },
+};

engine/jack.rs

@@ -0,0 +1,222 @@
+use crate::*;
+pub use ::jack::{*, contrib::{*, ClosureProcessHandler}};
+/// Wraps [JackState] and through it [jack::Client] when connected.
+#[derive(Clone, Debug, Default)]
+pub struct Jack<'j>(Arc<RwLock<JackState<'j>>>);
+/// Implement [Jack] constructor and methods
+impl<'j> Jack<'j> {
+    /// Register new [Client] and wrap it for shared use.
+    pub fn new_run <T: HasJack<'j> + Audio + Send + Sync + 'static> (
+        name: &impl AsRef<str>,
+        init: impl FnOnce(Jack<'j>)->Usually<T>
+    ) -> Usually<Arc<RwLock<T>>> {
+        Jack::new(name)?.run(init)
+    }
+    pub fn new (name: &impl AsRef<str>) -> Usually<Self> {
+        let client = Client::new(name.as_ref(), ClientOptions::NO_START_SERVER)?.0;
+        Ok(Jack(Arc::new(RwLock::new(JackState::Inactive(client)))))
+    }
+    pub fn run <T: HasJack<'j> + Audio + Send + Sync + 'static>
+        (self, init: impl FnOnce(Self)->Usually<T>) -> Usually<Arc<RwLock<T>>>
+    {
+        let client_state = self.0.clone();
+        let app: Arc<RwLock<T>> = Arc::new(RwLock::new(init(self)?));
+        let mut state = Activating;
+        std::mem::swap(&mut*client_state.write().unwrap(), &mut state);
+        if let Inactive(client) = state {
+            let client = client.activate_async(
+                // This is the misc notifications handler. It's a struct that wraps a [Box]
+                // which performs type erasure on a callback that takes [JackEvent], which is
+                // one of the available misc notifications.
+                Notifications(Box::new({
+                    let app = app.clone();
+                    move|event|(&mut*app.write().unwrap()).handle(event)
+                }) as BoxedJackEventHandler),
+                // This is the main processing handler. It's a struct that wraps a [Box]
+                // which performs type erasure on a callback that takes [Client] and [ProcessScope]
+                // and passes them down to the `app`'s `process` callback, which in turn
+                // implements audio and MIDI input and output on a realtime basis.
+                ClosureProcessHandler::new(Box::new({
+                    let app = app.clone();
+                    move|c: &_, s: &_|if let Ok(mut app) = app.write() {
+                        app.process(c, s)
+                    } else {
+                        Control::Quit
+                    }
+                }) as BoxedAudioHandler),
+            )?;
+            *client_state.write().unwrap() = Active(client);
+        } else {
+            unreachable!();
+        }
+        Ok(app)
+    }
+    /// Run something with the client.
+    pub fn with_client <T> (&self, op: impl FnOnce(&Client)->T) -> T {
+        match &*self.0.read().unwrap() {
+            Inert            => panic!("jack client not activated"),
+            Inactive(client) => op(client),
+            Activating       => panic!("jack client has not finished activation"),
+            Active(client)   => op(client.as_client()),
+        }
+    }
+}
+impl<'j> HasJack<'j> for Jack<'j> {
+    fn jack (&self) -> &Jack<'j> {
+        self
+    }
+}
+impl<'j> HasJack<'j> for &Jack<'j> {
+    fn jack (&self) -> &Jack<'j> {
+        self
+    }
+}
+/// This is a connection which may be [Inactive], [Activating], or [Active].
+/// In the [Active] and [Inactive] states, [JackState::client] returns a
+/// [jack::Client], which you can use to talk to the JACK API.
+#[derive(Debug, Default)]
+pub enum JackState<'j> {
+    /// Unused
+    #[default] Inert,
+    /// Before activation.
+    Inactive(Client),
+    /// During activation.
+    Activating,
+    /// After activation. Must not be dropped for JACK thread to persist.
+    Active(DynamicAsyncClient<'j>),
+}
+/// Things that can provide a [jack::Client] reference.
+pub trait HasJack<'j>: Send + Sync {
+    /// Return the internal [jack::Client] handle
+    /// that lets you call the JACK API.
+    fn jack (&self) -> &Jack<'j>;
+    fn with_client <T> (&self, op: impl FnOnce(&Client)->T) -> T {
+        self.jack().with_client(op)
+    }
+    fn port_by_name (&self, name: &str) -> Option<Port<Unowned>> {
+        self.with_client(|client|client.port_by_name(name))
+    }
+    fn port_by_id (&self, id: u32) -> Option<Port<Unowned>> {
+        self.with_client(|c|c.port_by_id(id))
+    }
+    fn register_port <PS: PortSpec + Default> (&self, name: impl AsRef<str>) -> Usually<Port<PS>> {
+        self.with_client(|client|Ok(client.register_port(name.as_ref(), PS::default())?))
+    }
+    fn sync_lead (&self, enable: bool, callback: impl Fn(TimebaseInfo)->Position) -> Usually<()> {
+        if enable {
+            self.with_client(|client|match client.register_timebase_callback(false, callback) {
+               Ok(_) => Ok(()),
+                Err(e) => Err(e)
+            })?
+        }
+        Ok(())
+    }
+    fn sync_follow (&self, _enable: bool) -> Usually<()> {
+        // TODO: sync follow
+        Ok(())
+    }
+}
+/// Trait for thing that has a JACK process callback.
+pub trait Audio {
+    /// Handle a JACK event.
+    fn handle (&mut self, _event: JackEvent) {}
+    /// Projecss a JACK chunk.
+    fn process (&mut self, _: &Client, _: &ProcessScope) -> Control {
+        Control::Continue
+    }
+    /// The JACK process callback function passed to the server.
+    fn callback (
+        state: &Arc<RwLock<Self>>, client: &Client, scope: &ProcessScope
+    ) -> Control where Self: Sized {
+        if let Ok(mut state) = state.write() {
+            state.process(client, scope)
+        } else {
+            Control::Quit
+        }
+    }
+}
+/// Implement [Audio]: provide JACK callbacks.
+#[macro_export] macro_rules! audio {
+    (|
+        $self1:ident:
+        $Struct:ident$(<$($L:lifetime),*$($T:ident$(:$U:path)?),*>)?,$c:ident,$s:ident
+    |$cb:expr$(;|$self2:ident,$e:ident|$cb2:expr)?) => {
+        impl $(<$($L),*$($T $(: $U)?),*>)? Audio for $Struct $(<$($L),*$($T),*>)? {
+            #[inline] fn process (&mut $self1, $c: &Client, $s: &ProcessScope) -> Control { $cb }
+            $(#[inline] fn handle (&mut $self2, $e: JackEvent) { $cb2 })?
+        }
+    }
+}
+/// Event enum for JACK events.
+#[derive(Debug, Clone, PartialEq)] pub enum JackEvent {
+    ThreadInit,
+    Shutdown(ClientStatus, Arc<str>),
+    Freewheel(bool),
+    SampleRate(Frames),
+    ClientRegistration(Arc<str>, bool),
+    PortRegistration(PortId, bool),
+    PortRename(PortId, Arc<str>, Arc<str>),
+    PortsConnected(PortId, PortId, bool),
+    GraphReorder,
+    XRun,
+}
+/// Generic notification handler that emits [JackEvent]
+pub struct Notifications<T: Fn(JackEvent) + Send>(pub T);
+
+impl<T: Fn(JackEvent) + Send> NotificationHandler for Notifications<T> {
+    fn thread_init(&self, _: &Client) {
+        self.0(JackEvent::ThreadInit);
+    }
+    unsafe fn shutdown(&mut self, status: ClientStatus, reason: &str) {
+        self.0(JackEvent::Shutdown(status, reason.into()));
+    }
+    fn freewheel(&mut self, _: &Client, enabled: bool) {
+        self.0(JackEvent::Freewheel(enabled));
+    }
+    fn sample_rate(&mut self, _: &Client, frames: Frames) -> Control {
+        self.0(JackEvent::SampleRate(frames));
+        Control::Quit
+    }
+    fn client_registration(&mut self, _: &Client, name: &str, reg: bool) {
+        self.0(JackEvent::ClientRegistration(name.into(), reg));
+    }
+    fn port_registration(&mut self, _: &Client, id: PortId, reg: bool) {
+        self.0(JackEvent::PortRegistration(id, reg));
+    }
+    fn port_rename(&mut self, _: &Client, id: PortId, old: &str, new: &str) -> Control {
+        self.0(JackEvent::PortRename(id, old.into(), new.into()));
+        Control::Continue
+    }
+    fn ports_connected(&mut self, _: &Client, a: PortId, b: PortId, are: bool) {
+        self.0(JackEvent::PortsConnected(a, b, are));
+    }
+    fn graph_reorder(&mut self, _: &Client) -> Control {
+        self.0(JackEvent::GraphReorder);
+        Control::Continue
+    }
+    fn xrun(&mut self, _: &Client) -> Control {
+        self.0(JackEvent::XRun);
+        Control::Continue
+    }
+}
+
+/// This is a running JACK [AsyncClient] with maximum type erasure.
+/// It has one [Box] containing a function that handles [JackEvent]s,
+/// and another [Box] containing a function that handles realtime IO,
+/// and that's all it knows about them.
+pub type DynamicAsyncClient<'j>
+    = AsyncClient<DynamicNotifications<'j>, DynamicAudioHandler<'j>>;
+/// This is the notification handler wrapper for a boxed realtime callback.
+pub type DynamicAudioHandler<'j> =
+    ClosureProcessHandler<(), BoxedAudioHandler<'j>>;
+/// This is a boxed realtime callback.
+pub type BoxedAudioHandler<'j> =
+    Box<dyn FnMut(&Client, &ProcessScope) -> Control + Send + Sync + 'j>;
+/// This is the notification handler wrapper for a boxed [JackEvent] callback.
+pub type DynamicNotifications<'j> =
+    Notifications<BoxedJackEventHandler<'j>>;
+/// This is a boxed [JackEvent] callback.
+pub type BoxedJackEventHandler<'j> =
+    Box<dyn Fn(JackEvent) + Send + Sync + 'j>;
+use self::JackState::*;
+

engine/midi.rs

@@ -0,0 +1,35 @@
+pub use ::midly::{
+    Smf,
+    TrackEventKind,
+    MidiMessage,
+    Error as MidiError,
+    num::*,
+    live::*,
+};
+
+/// Return boxed iterator of MIDI events
+pub fn parse_midi_input <'a> (input: ::jack::MidiIter<'a>) -> Box<dyn Iterator<Item=(usize, LiveEvent<'a>, &'a [u8])> + 'a> {
+    Box::new(input.map(|::jack::RawMidi { time, bytes }|(
+        time as usize,
+        LiveEvent::parse(bytes).unwrap(),
+        bytes
+    )))
+}
+
+/// Add "all notes off" to the start of a buffer.
+pub fn all_notes_off (output: &mut [Vec<Vec<u8>>]) {
+    let mut buf = vec![];
+    let msg = MidiMessage::Controller { controller: 123.into(), value: 0.into() };
+    let evt = LiveEvent::Midi { channel: 0.into(), message: msg };
+    evt.write(&mut buf).unwrap();
+    output[0].push(buf);
+}
+
+/// Update notes_in array
+pub fn update_keys (keys: &mut[bool;128], message: &MidiMessage) {
+    match message {
+        MidiMessage::NoteOn  { key, .. } => { keys[key.as_int() as usize] = true; }
+        MidiMessage::NoteOff { key, .. } => { keys[key.as_int() as usize] = false; },
+        _ => {}
+    }
+}

engine/note.rs

@@ -0,0 +1,3 @@
+mod note_pitch; pub use self::note_pitch::*;
+mod note_point; pub use self::note_point::*;
+mod note_range; pub use self::note_range::*;

engine/note/note_pitch.rs

@@ -0,0 +1,23 @@
+pub struct Note;
+
+impl Note {
+    pub const NAMES: [&str; 128] = [
+        "C0",  "C#0",  "D0",  "D#0",  "E0",  "F0",  "F#0",  "G0", "G#0", "A0", "A#0", "B0",
+        "C1",  "C#1",  "D1",  "D#1",  "E1",  "F1",  "F#1",  "G1", "G#1", "A1", "A#1", "B1",
+        "C2",  "C#2",  "D2",  "D#2",  "E2",  "F2",  "F#2",  "G2", "G#2", "A2", "A#2", "B2",
+        "C3",  "C#3",  "D3",  "D#3",  "E3",  "F3",  "F#3",  "G3", "G#3", "A3", "A#3", "B3",
+        "C4",  "C#4",  "D4",  "D#4",  "E4",  "F4",  "F#4",  "G4", "G#4", "A4", "A#4", "B4",
+        "C5",  "C#5",  "D5",  "D#5",  "E5",  "F5",  "F#5",  "G5", "G#5", "A5", "A#5", "B5",
+        "C6",  "C#6",  "D6",  "D#6",  "E6",  "F6",  "F#6",  "G6", "G#6", "A6", "A#6", "B6",
+        "C7",  "C#7",  "D7",  "D#7",  "E7",  "F7",  "F#7",  "G7", "G#7", "A7", "A#7", "B7",
+        "C8",  "C#8",  "D8",  "D#8",  "E8",  "F8",  "F#8",  "G8", "G#8", "A8", "A#8", "B8",
+        "C9",  "C#9",  "D9",  "D#9",  "E9",  "F9",  "F#9",  "G9", "G#9", "A9", "A#9", "B9",
+        "C10", "C#10", "D10", "D#10", "E10", "F10", "F#10", "G10",
+    ];
+    pub fn pitch_to_name (n: usize) -> &'static str {
+        if n > 127 {
+            panic!("to_note_name({n}): must be 0-127");
+        }
+        Self::NAMES[n]
+    }
+}

engine/note/note_point.rs

@@ -0,0 +1,79 @@
+use crate::*;
+
+#[derive(Debug, Clone)]
+pub struct MidiPointModel {
+    /// Time coordinate of cursor
+    pub time_pos: Arc<AtomicUsize>,
+    /// Note coordinate of cursor
+    pub note_pos: Arc<AtomicUsize>,
+    /// Length of note that will be inserted, in pulses
+    pub note_len: Arc<AtomicUsize>,
+}
+
+impl Default for MidiPointModel {
+    fn default () -> Self {
+        Self {
+            time_pos: Arc::new(0.into()),
+            note_pos: Arc::new(36.into()),
+            note_len: Arc::new(24.into()),
+        }
+    }
+}
+
+impl NotePoint for MidiPointModel {
+    fn note_len (&self) -> &AtomicUsize {
+        &self.note_len
+    }
+    fn note_pos (&self) -> &AtomicUsize {
+        &self.note_pos
+    }
+}
+
+impl TimePoint for MidiPointModel {
+    fn time_pos (&self) -> &AtomicUsize {
+        self.time_pos.as_ref()
+    }
+}
+
+pub trait NotePoint {
+    fn note_len (&self) -> &AtomicUsize;
+    /// Get the current length of the note cursor.
+    fn get_note_len (&self) -> usize {
+        self.note_len().load(Relaxed)
+    }
+    /// Set the length of the note cursor, returning the previous value.
+    fn set_note_len (&self, x: usize) -> usize {
+        self.note_len().swap(x, Relaxed)
+    }
+
+    fn note_pos (&self) -> &AtomicUsize;
+    /// Get the current pitch of the note cursor.
+    fn get_note_pos (&self) -> usize {
+        self.note_pos().load(Relaxed).min(127)
+    }
+    /// Set the current pitch fo the note cursor, returning the previous value.
+    fn set_note_pos (&self, x: usize) -> usize {
+        self.note_pos().swap(x.min(127), Relaxed)
+    }
+}
+
+pub trait TimePoint {
+    fn time_pos (&self) -> &AtomicUsize;
+    /// Get the current time position of the note cursor.
+    fn get_time_pos (&self) -> usize {
+        self.time_pos().load(Relaxed)
+    }
+    /// Set the current time position of the note cursor, returning the previous value.
+    fn set_time_pos (&self, x: usize) -> usize {
+        self.time_pos().swap(x, Relaxed)
+    }
+}
+
+pub trait MidiPoint: NotePoint + TimePoint {
+    /// Get the current end of the note cursor.
+    fn get_note_end (&self) -> usize {
+        self.get_time_pos() + self.get_note_len()
+    }
+}
+
+impl<T: NotePoint + TimePoint> MidiPoint for T {}

engine/note/note_range.rs

@@ -0,0 +1,98 @@
+use crate::*;
+use std::sync::atomic::Ordering;
+
+#[derive(Debug, Clone)]
+pub struct MidiRangeModel {
+    pub time_len:   Arc<AtomicUsize>,
+    /// Length of visible time axis
+    pub time_axis:  Arc<AtomicUsize>,
+    /// Earliest time displayed
+    pub time_start: Arc<AtomicUsize>,
+    /// Time step
+    pub time_zoom:  Arc<AtomicUsize>,
+    /// Auto rezoom to fit in time axis
+    pub time_lock:  Arc<AtomicBool>,
+    /// Length of visible note axis
+    pub note_axis:  Arc<AtomicUsize>,
+    // Lowest note displayed
+    pub note_lo:    Arc<AtomicUsize>,
+}
+
+from!(|data:(usize, bool)|MidiRangeModel = Self {
+    time_len:   Arc::new(0.into()),
+    note_axis:  Arc::new(0.into()),
+    note_lo:    Arc::new(0.into()),
+    time_axis:  Arc::new(0.into()),
+    time_start: Arc::new(0.into()),
+    time_zoom:  Arc::new(data.0.into()),
+    time_lock:  Arc::new(data.1.into()),
+});
+
+pub trait TimeRange {
+    fn time_len (&self) -> &AtomicUsize;
+    fn get_time_len (&self) -> usize {
+        self.time_len().load(Ordering::Relaxed)
+    }
+    fn time_zoom (&self) -> &AtomicUsize;
+    fn get_time_zoom (&self) -> usize {
+        self.time_zoom().load(Ordering::Relaxed)
+    }
+    fn set_time_zoom (&self, value: usize) -> usize {
+        self.time_zoom().swap(value, Ordering::Relaxed)
+    }
+    fn time_lock (&self) -> &AtomicBool;
+    fn get_time_lock (&self) -> bool {
+        self.time_lock().load(Ordering::Relaxed)
+    }
+    fn set_time_lock (&self, value: bool) -> bool {
+        self.time_lock().swap(value, Ordering::Relaxed)
+    }
+    fn time_start (&self) -> &AtomicUsize;
+    fn get_time_start (&self) -> usize {
+        self.time_start().load(Ordering::Relaxed)
+    }
+    fn set_time_start (&self, value: usize) -> usize {
+        self.time_start().swap(value, Ordering::Relaxed)
+    }
+    fn time_axis (&self) -> &AtomicUsize;
+    fn get_time_axis (&self) -> usize {
+        self.time_axis().load(Ordering::Relaxed)
+    }
+    fn get_time_end (&self) -> usize {
+        self.time_start().get() + self.time_axis().get() * self.time_zoom().get()
+    }
+}
+
+pub trait NoteRange {
+    fn note_lo (&self) -> &AtomicUsize;
+    fn get_note_lo (&self) -> usize {
+        self.note_lo().load(Ordering::Relaxed)
+    }
+    fn set_note_lo (&self, x: usize) -> usize {
+        self.note_lo().swap(x, Ordering::Relaxed)
+    }
+    fn note_axis (&self) -> &AtomicUsize;
+    fn get_note_axis (&self) -> usize {
+        self.note_axis().load(Ordering::Relaxed)
+    }
+    fn get_note_hi (&self) -> usize {
+        (self.note_lo().get() + self.note_axis().get().saturating_sub(1)).min(127)
+    }
+}
+
+pub trait MidiRange: TimeRange + NoteRange {}
+
+impl<T: TimeRange + NoteRange> MidiRange for T {}
+
+impl TimeRange for MidiRangeModel {
+    fn time_len   (&self) -> &AtomicUsize { &self.time_len   }
+    fn time_zoom  (&self) -> &AtomicUsize { &self.time_zoom  }
+    fn time_lock  (&self) -> &AtomicBool  { &self.time_lock  }
+    fn time_start (&self) -> &AtomicUsize { &self.time_start }
+    fn time_axis  (&self) -> &AtomicUsize { &self.time_axis  }
+}
+
+impl NoteRange for MidiRangeModel {
+    fn note_lo    (&self) -> &AtomicUsize { &self.note_lo    }
+    fn note_axis  (&self) -> &AtomicUsize { &self.note_axis  }
+}

engine/time.rs

@@ -0,0 +1,9 @@
+mod time_moment;       pub use self::time_moment::*;
+mod time_note;         pub use self::time_note::*;
+mod time_perf;         pub use self::time_perf::*;
+mod time_pulse;        pub use self::time_pulse::*;
+mod time_sample_count; pub use self::time_sample_count::*;
+mod time_sample_rate;  pub use self::time_sample_rate::*;
+mod time_timebase;     pub use self::time_timebase::*;
+mod time_unit;         pub use self::time_unit::*;
+mod time_usec;         pub use self::time_usec::*;

engine/time/time_moment.rs

@@ -0,0 +1,70 @@
+use crate::*;
+
+#[derive(Debug, Clone)]
+pub enum Moment2 {
+    None,
+    Zero,
+    Usec(Microsecond),
+    Sample(SampleCount),
+    Pulse(Pulse),
+}
+
+/// A point in time in all time scales (microsecond, sample, MIDI pulse)
+#[derive(Debug, Default, Clone)]
+pub struct Moment {
+    pub timebase: Arc<Timebase>,
+    /// Current time in microseconds
+    pub usec:   Microsecond,
+    /// Current time in audio samples
+    pub sample: SampleCount,
+    /// Current time in MIDI pulses
+    pub pulse:  Pulse,
+}
+
+impl Moment {
+    pub fn zero (timebase: &Arc<Timebase>) -> Self {
+        Self { usec: 0.into(), sample: 0.into(), pulse: 0.into(), timebase: timebase.clone() }
+    }
+    pub fn from_usec (timebase: &Arc<Timebase>, usec: f64) -> Self {
+        Self {
+            usec:     usec.into(),
+            sample:   timebase.sr.usecs_to_sample(usec).into(),
+            pulse:    timebase.usecs_to_pulse(usec).into(),
+            timebase: timebase.clone(),
+        }
+    }
+    pub fn from_sample (timebase: &Arc<Timebase>, sample: f64) -> Self {
+        Self {
+            sample:   sample.into(),
+            usec:     timebase.sr.samples_to_usec(sample).into(),
+            pulse:    timebase.samples_to_pulse(sample).into(),
+            timebase: timebase.clone(),
+        }
+    }
+    pub fn from_pulse (timebase: &Arc<Timebase>, pulse: f64) -> Self {
+        Self {
+            pulse:    pulse.into(),
+            sample:   timebase.pulses_to_sample(pulse).into(),
+            usec:     timebase.pulses_to_usec(pulse).into(),
+            timebase: timebase.clone(),
+        }
+    }
+    #[inline] pub fn update_from_usec (&self, usec: f64) {
+        self.usec.set(usec);
+        self.pulse.set(self.timebase.usecs_to_pulse(usec));
+        self.sample.set(self.timebase.sr.usecs_to_sample(usec));
+    }
+    #[inline] pub fn update_from_sample (&self, sample: f64) {
+        self.usec.set(self.timebase.sr.samples_to_usec(sample));
+        self.pulse.set(self.timebase.samples_to_pulse(sample));
+        self.sample.set(sample);
+    }
+    #[inline] pub fn update_from_pulse (&self, pulse: f64) {
+        self.usec.set(self.timebase.pulses_to_usec(pulse));
+        self.pulse.set(pulse);
+        self.sample.set(self.timebase.pulses_to_sample(pulse));
+    }
+    #[inline] pub fn format_beat (&self) -> Arc<str> {
+        self.timebase.format_beats_1(self.pulse.get()).into()
+    }
+}

engine/time/time_note.rs

@@ -0,0 +1,35 @@
+pub struct NoteDuration;
+
+/// (pulses, name), assuming 96 PPQ
+pub const NOTE_DURATIONS: [(usize, &str);26] = [
+    (1,    "1/384"), (2,    "1/192"),
+    (3,    "1/128"), (4,    "1/96"),
+    (6,    "1/64"),  (8,    "1/48"),
+    (12,   "1/32"),  (16,   "1/24"),
+    (24,   "1/16"),  (32,   "1/12"),
+    (48,   "1/8"),   (64,   "1/6"),
+    (96,   "1/4"),   (128,  "1/3"),
+    (192,  "1/2"),   (256,  "2/3"),
+    (384,  "1/1"),   (512,  "4/3"),
+    (576,  "3/2"),   (768,  "2/1"),
+    (1152, "3/1"),   (1536, "4/1"),
+    (2304, "6/1"),   (3072, "8/1"),
+    (3456, "9/1"),   (6144, "16/1"),
+];
+
+impl NoteDuration {
+    /// Returns the next shorter length
+    pub fn prev (pulses: usize) -> usize {
+        for (length, _) in NOTE_DURATIONS.iter().rev() { if *length < pulses { return *length } }
+        pulses
+    }
+    /// Returns the next longer length
+    pub fn next (pulses: usize) -> usize {
+        for (length, _) in NOTE_DURATIONS.iter() { if *length > pulses { return *length } }
+        pulses
+    }
+    pub fn pulses_to_name (pulses: usize) -> &'static str {
+        for (length, name) in NOTE_DURATIONS.iter() { if *length == pulses { return name } }
+        ""
+    }
+}

engine/time/time_perf.rs

@@ -0,0 +1,23 @@
+use crate::*;
+use tengri::tui::PerfModel;
+use ::jack::ProcessScope;
+
+pub trait JackPerfModel {
+    fn update_from_jack_scope (&self, t0: Option<u64>, scope: &ProcessScope);
+}
+
+impl JackPerfModel for PerfModel {
+    fn update_from_jack_scope (&self, t0: Option<u64>, scope: &ProcessScope) {
+        if let Some(t0) = t0 {
+            let t1 = self.clock.raw();
+            self.used.store(
+                self.clock.delta_as_nanos(t0, t1) as f64,
+                Relaxed,
+            );
+            self.window.store(
+                scope.cycle_times().unwrap().period_usecs as f64,
+                Relaxed,
+            );
+        }
+    }
+}

engine/time/time_pulse.rs

@@ -0,0 +1,71 @@
+use crate::*;
+
+pub const DEFAULT_PPQ: f64 = 96.0;
+
+/// FIXME: remove this and use PPQ from timebase everywhere:
+pub const PPQ: usize = 96;
+
+/// MIDI resolution in PPQ (pulses per quarter note)
+#[derive(Debug, Default)] pub struct PulsesPerQuaver(AtomicF64);
+impl_time_unit!(PulsesPerQuaver);
+
+/// Timestamp in MIDI pulses
+#[derive(Debug, Default)] pub struct Pulse(AtomicF64);
+impl_time_unit!(Pulse);
+
+/// Tempo in beats per minute
+#[derive(Debug, Default)] pub struct BeatsPerMinute(AtomicF64);
+impl_time_unit!(BeatsPerMinute);
+
+/// Quantization setting for launching clips
+#[derive(Debug, Default)] pub struct LaunchSync(AtomicF64);
+impl_time_unit!(LaunchSync);
+impl LaunchSync {
+    pub fn next (&self) -> f64 {
+        NoteDuration::next(self.get() as usize) as f64
+    }
+    pub fn prev (&self) -> f64 {
+        NoteDuration::prev(self.get() as usize) as f64
+    }
+}
+
+/// Quantization setting for notes
+#[derive(Debug, Default)] pub struct Quantize(AtomicF64);
+impl_time_unit!(Quantize);
+impl Quantize {
+    pub fn next (&self) -> f64 {
+        NoteDuration::next(self.get() as usize) as f64
+    }
+    pub fn prev (&self) -> f64 {
+        NoteDuration::prev(self.get() as usize) as f64
+    }
+}
+
+/// Iterator that emits subsequent ticks within a range.
+pub struct TicksIterator {
+    pub spp:    f64,
+    pub sample: usize,
+    pub start:  usize,
+    pub end:    usize,
+}
+impl Iterator for TicksIterator {
+    type Item = (usize, usize);
+    fn next (&mut self) -> Option<Self::Item> {
+        loop {
+            if self.sample > self.end { return None }
+            let spp    = self.spp;
+            let sample = self.sample as f64;
+            let start  = self.start;
+            let end    = self.end;
+            self.sample += 1;
+            //println!("{spp} {sample} {start} {end}");
+            let jitter = sample.rem_euclid(spp); // ramps
+            let next_jitter = (sample + 1.0).rem_euclid(spp);
+            if jitter > next_jitter { // at crossing:
+                let time = (sample as usize) % (end as usize-start as usize);
+                let tick = (sample / spp) as usize;
+                return Some((time, tick))
+            }
+        }
+    }
+}

engine/time/time_sample_count.rs

@@ -0,0 +1,5 @@
+use crate::*;
+
+/// Timestamp in audio samples
+#[derive(Debug, Default)] pub struct SampleCount(AtomicF64);
+impl_time_unit!(SampleCount);

engine/time/time_sample_rate.rs

@@ -0,0 +1,23 @@
+use crate::*;
+
+/// Audio sample rate in Hz (samples per second)
+#[derive(Debug, Default)] pub struct SampleRate(AtomicF64);
+impl_time_unit!(SampleRate);
+impl SampleRate {
+    /// Return the duration of a sample in microseconds (floating)
+    #[inline] pub fn usec_per_sample (&self) -> f64 {
+        1_000_000f64 / self.get()
+    }
+    /// Return the duration of a sample in microseconds (floating)
+    #[inline] pub fn sample_per_usec (&self) -> f64 {
+        self.get() / 1_000_000f64
+    }
+    /// Convert a number of samples to microseconds (floating)
+    #[inline] pub fn samples_to_usec (&self, samples: f64) -> f64 {
+        self.usec_per_sample() * samples
+    }
+    /// Convert a number of microseconds to samples (floating)
+    #[inline] pub fn usecs_to_sample (&self, usecs:   f64) -> f64 {
+        self.sample_per_usec() * usecs
+    }
+}

engine/time/time_timebase.rs

@@ -0,0 +1,118 @@
+use crate::*;
+
+/// Temporal resolutions: sample rate, tempo, MIDI pulses per quaver (beat)
+#[derive(Debug, Clone)]
+pub struct Timebase {
+    /// Audio samples per second
+    pub sr:  SampleRate,
+    /// MIDI beats per minute
+    pub bpm: BeatsPerMinute,
+    /// MIDI ticks per beat
+    pub ppq: PulsesPerQuaver,
+}
+
+impl Timebase {
+    /// Specify sample rate, BPM and PPQ
+    pub fn new (
+        s: impl Into<SampleRate>,
+        b: impl Into<BeatsPerMinute>,
+        p: impl Into<PulsesPerQuaver>
+    ) -> Self {
+        Self { sr: s.into(), bpm: b.into(), ppq: p.into() }
+    }
+    /// Iterate over ticks between start and end.
+    #[inline] pub fn pulses_between_samples (&self, start: usize, end: usize) -> TicksIterator {
+        TicksIterator { spp: self.samples_per_pulse(), sample: start, start, end }
+    }
+    /// Return the duration fo a beat in microseconds
+    #[inline] pub fn usec_per_beat (&self) -> f64 { 60_000_000f64 / self.bpm.get() }
+    /// Return the number of beats in a second
+    #[inline] pub fn beat_per_second (&self) -> f64 { self.bpm.get() / 60f64 }
+    /// Return the number of microseconds corresponding to a note of the given duration
+    #[inline] pub fn note_to_usec (&self, (num, den): (f64, f64)) -> f64 {
+        4.0 * self.usec_per_beat() * num / den
+    }
+    /// Return duration of a pulse in microseconds (BPM-dependent)
+    #[inline] pub fn pulse_per_usec (&self) -> f64 { self.ppq.get() / self.usec_per_beat() }
+    /// Return duration of a pulse in microseconds (BPM-dependent)
+    #[inline] pub fn usec_per_pulse (&self) -> f64 { self.usec_per_beat() / self.ppq.get() }
+    /// Return number of pulses to which a number of microseconds corresponds (BPM-dependent)
+    #[inline] pub fn usecs_to_pulse (&self, usec: f64) -> f64 { usec * self.pulse_per_usec() }
+    /// Convert a number of pulses to a sample number (SR- and BPM-dependent)
+    #[inline] pub fn pulses_to_usec (&self, pulse: f64) -> f64 { pulse / self.usec_per_pulse() }
+    /// Return number of pulses in a second (BPM-dependent)
+    #[inline] pub fn pulses_per_second (&self) -> f64 { self.beat_per_second() * self.ppq.get() }
+    /// Return fraction of a pulse to which a sample corresponds (SR- and BPM-dependent)
+    #[inline] pub fn pulses_per_sample (&self) -> f64 {
+        self.usec_per_pulse() / self.sr.usec_per_sample()
+    }
+    /// Return number of samples in a pulse (SR- and BPM-dependent)
+    #[inline] pub fn samples_per_pulse (&self) -> f64 {
+        self.sr.get() / self.pulses_per_second()
+    }
+    /// Convert a number of pulses to a sample number (SR- and BPM-dependent)
+    #[inline] pub fn pulses_to_sample (&self, p: f64) -> f64 {
+        self.pulses_per_sample() * p
+    }
+    /// Convert a number of samples to a pulse number (SR- and BPM-dependent)
+    #[inline] pub fn samples_to_pulse (&self, s: f64) -> f64 {
+        s / self.pulses_per_sample()
+    }
+    /// Return the number of samples corresponding to a note of the given duration
+    #[inline] pub fn note_to_samples (&self, note: (f64, f64)) -> f64 {
+        self.usec_to_sample(self.note_to_usec(note))
+    }
+    /// Return the number of samples corresponding to the given number of microseconds
+    #[inline] pub fn usec_to_sample (&self, usec: f64) -> f64 {
+        usec * self.sr.get() / 1000f64
+    }
+    /// Return the quantized position of a moment in time given a step
+    #[inline] pub fn quantize (&self, step: (f64, f64), time: f64) -> (f64, f64) {
+        let step = self.note_to_usec(step);
+        (time / step, time % step)
+    }
+    /// Quantize a collection of events
+    #[inline] pub fn quantize_into <E: Iterator<Item=(f64, f64)> + Sized, T> (
+        &self, step: (f64, f64), events: E
+    ) -> Vec<(f64, f64)> {
+        events.map(|(time, event)|(self.quantize(step, time).0, event)).collect()
+    }
+    /// Format a number of pulses into Beat.Bar.Pulse starting from 0
+    #[inline] pub fn format_beats_0 (&self, pulse: f64) -> Arc<str> {
+        let pulse = pulse as usize;
+        let ppq   = self.ppq.get() as usize;
+        let (beats, pulses) = if ppq > 0 { (pulse / ppq, pulse % ppq) } else { (0, 0) };
+        format!("{}.{}.{pulses:02}", beats / 4, beats % 4).into()
+    }
+    /// Format a number of pulses into Beat.Bar starting from 0
+    #[inline] pub fn format_beats_0_short (&self, pulse: f64) -> Arc<str> {
+        let pulse = pulse as usize;
+        let ppq   = self.ppq.get() as usize;
+        let beats = if ppq > 0 { pulse / ppq } else { 0 };
+        format!("{}.{}", beats / 4, beats % 4).into()
+    }
+    /// Format a number of pulses into Beat.Bar.Pulse starting from 1
+    #[inline] pub fn format_beats_1 (&self, pulse: f64) -> Arc<str> {
+        let mut string = String::with_capacity(16);
+        self.format_beats_1_to(&mut string, pulse).expect("failed to format {pulse} into beat");
+        string.into()
+    }
+    /// Format a number of pulses into Beat.Bar.Pulse starting from 1
+    #[inline] pub fn format_beats_1_to (&self, w: &mut impl std::fmt::Write, pulse: f64) -> Result<(), std::fmt::Error> {
+        let pulse = pulse as usize;
+        let ppq   = self.ppq.get() as usize;
+        let (beats, pulses) = if ppq > 0 { (pulse / ppq, pulse % ppq) } else { (0, 0) };
+        write!(w, "{}.{}.{pulses:02}", beats / 4 + 1, beats % 4 + 1)
+    }
+    /// Format a number of pulses into Beat.Bar.Pulse starting from 1
+    #[inline] pub fn format_beats_1_short (&self, pulse: f64) -> Arc<str> {
+        let pulse = pulse as usize;
+        let ppq   = self.ppq.get() as usize;
+        let beats = if ppq > 0 { pulse / ppq } else { 0 };
+        format!("{}.{}", beats / 4 + 1, beats % 4 + 1).into()
+    }
+}
+
+impl Default for Timebase {
+    fn default () -> Self { Self::new(48000f64, 150f64, DEFAULT_PPQ) }
+}

engine/time/time_unit.rs

@@ -0,0 +1,59 @@
+use crate::*;
+
+/// A unit of time, represented as an atomic 64-bit float.
+///
+/// According to https://stackoverflow.com/a/873367, as per IEEE754,
+/// every integer between 1 and 2^53 can be represented exactly.
+/// This should mean that, even at 192kHz sampling rate, over 1 year of audio
+/// can be clocked in microseconds with f64 without losing precision.
+pub trait TimeUnit: InteriorMutable<f64> {}
+
+/// Implement an arithmetic operation for a unit of time
+#[macro_export] macro_rules! impl_op {
+    ($T:ident, $Op:ident, $method:ident, |$a:ident,$b:ident|{$impl:expr}) => {
+        impl $Op<Self> for $T {
+            type Output = Self; #[inline] fn $method (self, other: Self) -> Self::Output {
+                let $a = self.get(); let $b = other.get(); Self($impl.into())
+            }
+        }
+        impl $Op<usize> for $T {
+            type Output = Self; #[inline] fn $method (self, other: usize) -> Self::Output {
+                let $a = self.get(); let $b = other as f64; Self($impl.into())
+            }
+        }
+        impl $Op<f64> for $T {
+            type Output = Self; #[inline] fn $method (self, other: f64) -> Self::Output {
+                let $a = self.get(); let $b = other; Self($impl.into())
+            }
+        }
+    }
+}
+
+/// Define and implement a unit of time
+#[macro_export] macro_rules! impl_time_unit {
+    ($T:ident) => {
+        impl Gettable<f64> for $T {
+            fn get (&self) -> f64 { self.0.load(Relaxed) }
+        }
+        impl InteriorMutable<f64> for $T {
+            fn set (&self, value: f64) -> f64 {
+                let old = self.get();
+                self.0.store(value, Relaxed);
+                old
+            }
+        }
+        impl TimeUnit for $T {}
+        impl_op!($T, Add, add, |a, b|{a + b});
+        impl_op!($T, Sub, sub, |a, b|{a - b});
+        impl_op!($T, Mul, mul, |a, b|{a * b});
+        impl_op!($T, Div, div, |a, b|{a / b});
+        impl_op!($T, Rem, rem, |a, b|{a % b});
+        impl From<f64>   for $T    { fn from (value: f64)   -> Self { Self(value.into()) } }
+        impl From<usize> for $T    { fn from (value: usize) -> Self { Self((value as f64).into()) } }
+        impl From<$T>    for f64   { fn from (value: $T)    -> Self { value.get() } }
+        impl From<$T>    for usize { fn from (value: $T)    -> Self { value.get() as usize } }
+        impl From<&$T>   for f64   { fn from (value: &$T)   -> Self { value.get() } }
+        impl From<&$T>   for usize { fn from (value: &$T)   -> Self { value.get() as usize } }
+        impl Clone for $T { fn clone (&self) -> Self { Self(self.get().into()) } }
+    }
+}

engine/time/time_usec.rs

@@ -0,0 +1,15 @@
+use crate::*;
+
+/// Timestamp in microseconds
+#[derive(Debug, Default)] pub struct Microsecond(AtomicF64);
+
+impl_time_unit!(Microsecond);
+
+impl Microsecond {
+    #[inline] pub fn format_msu (&self) -> Arc<str> {
+        let usecs              = self.get() as usize;
+        let (seconds, msecs)   = (usecs / 1000000, usecs / 1000 % 1000);
+        let (minutes, seconds) = (seconds / 60, seconds % 60);
+        format!("{minutes}:{seconds:02}:{msecs:03}").into()
+    }
+}