Fixes for global start beat handling

engine/note_container/src/exports.rs

@@ -132,12 +132,16 @@ pub fn iter_notes(
 /// 1. an `is_attack` flag which is true if the note is starting and false if the note is ending
 /// 2. line index
 /// 3. beat
+///
+/// If `include_partial_notes` is true, then notes that intersect the start or end of the selection
+/// will be included but truncated to the bounds of the selection.
 #[wasm_bindgen]
 pub fn iter_notes_with_cb(
   lines: *const NoteLines,
   start_beat_inclusive: f64,
   end_beat_exclusive: f64,
   cb: Function,
+  include_partial_notes: bool,
 ) {
   let notes = unsafe { &*lines };
 
@@ -147,8 +151,14 @@ pub fn iter_notes_with_cb(
     note: Note,
   }
 
+  struct NoteEvent {
+    is_attack: bool,
+    line_ix: usize,
+    beat: f64,
+  }
+
   let mut unreleased_notes: HashMap<u32, UnreleasedNote> = HashMap::default();
-  let mut events: Vec<(bool, usize, f64)> = Vec::default();
+  let mut events: Vec<NoteEvent> = Vec::default();
   let iter = notes.lines.iter().enumerate().flat_map(|(line_ix, line)| {
     line
       .inner
@@ -165,7 +175,11 @@ pub fn iter_notes_with_cb(
   for (line_ix, pos, entry) in iter {
     match entry {
       NoteEntry::NoteStart { note } => {
-        events.push((true, line_ix, pos));
+        events.push(NoteEvent {
+          is_attack: true,
+          line_ix,
+          beat: pos,
+        });
         let existing = unreleased_notes.insert(note.id, UnreleasedNote {
           line_ix,
           start_point: pos,
@@ -178,8 +192,21 @@ pub fn iter_notes_with_cb(
       },
       NoteEntry::NoteEnd { note_id } => {
         let existing = unreleased_notes.remove(&note_id);
-        if existing.is_some() {
-          events.push((false, line_ix, pos));
+
+        if existing.is_none() && include_partial_notes {
+          events.push(NoteEvent {
+            is_attack: true,
+            line_ix,
+            beat: start_beat_inclusive,
+          });
+        }
+
+        if existing.is_some() || include_partial_notes {
+          events.push(NoteEvent {
+            is_attack: false,
+            line_ix,
+            beat: pos,
+          });
         }
       },
       NoteEntry::StartAndEnd {
@@ -189,10 +216,18 @@ pub fn iter_notes_with_cb(
         // release before attack
         let existing = unreleased_notes.remove(&end_note_id);
         if existing.is_some() {
-          events.push((false, line_ix, pos));
+          events.push(NoteEvent {
+            is_attack: false,
+            line_ix,
+            beat: pos,
+          });
         }
 
-        events.push((true, line_ix, pos));
+        events.push(NoteEvent {
+          is_attack: true,
+          line_ix,
+          beat: pos,
+        });
         let existing = unreleased_notes.insert(start_note.id, UnreleasedNote {
           line_ix,
           start_point: pos,
@@ -212,10 +247,27 @@ pub fn iter_notes_with_cb(
   }
   for note in unreleased_notes.values() {
     let release_time = note.start_point + note.note.length;
-    events.push((false, note.line_ix, release_time));
+    events.push(NoteEvent {
+      is_attack: false,
+      line_ix: note.line_ix,
+      beat: release_time,
+    });
   }
 
-  for (is_attack, line_ix, beat) in events {
+  events.sort_unstable_by(|a, b| {
+    FloatOrd(a.beat)
+      .cmp(&FloatOrd(b.beat))
+      .then_with(|| a.line_ix.cmp(&b.line_ix))
+      // attacks before releases
+      .then_with(|| a.is_attack.cmp(&b.is_attack).reverse())
+  });
+
+  for NoteEvent {
+    is_attack,
+    line_ix,
+    beat,
+  } in events
+  {
     let _ = cb.call3(
       &JsValue::NULL,
       &JsValue::from(is_attack),

public/SequencerWorkletProcessor.js

@@ -16,8 +16,8 @@ class SequencerWorkletProcessor extends AudioWorkletProcessor {
           break;
         }
         case 'start': {
-          this.startBeat = globalThis.curBeat;
-          this.lastBeat = -1;
+          this.startBeat = evt.data.startBeat ?? globalThis.curBeat;
+          this.lastBeat = Math.trunc(evt.data.startBeat / this.config.beatRatio);
           break;
         }
         case 'stop': {
@@ -44,7 +44,7 @@ class SequencerWorkletProcessor extends AudioWorkletProcessor {
       return true;
     }
 
-    const beatsSinceStart = globalThis.curBeat - this.startBeat;
+    const beatsSinceStart = globalThis.curBeat;
     const curQuantizedBeat = Math.trunc(beatsSinceStart / this.config.beatRatio);
 
     if (curQuantizedBeat !== this.lastBeat) {

src/eventScheduler/eventScheduler.ts

@@ -107,7 +107,7 @@ export const useIsGlobalBeatCounterStarted = () => {
  *
  * Triggers all callbacks registered with `addStartCB` to be called.
  */
-export const startAll = (startBeat = 0) => {
+export const startAll = (startBeat = getCurBeat()) => {
   if (isStarted) {
     console.warn("Tried to start global beat counter, but it's already started");
     return;

src/midiEditor/MIDIEditorUIManager.tsx

@@ -157,7 +157,8 @@ export class ManagedMIDIEditorUIInstance {
       noteLinesCtxPtr,
       startBeatInclusive ?? 0,
       endBeatExclusive ?? -1,
-      cb
+      cb,
+      true
     );
   };
 

src/midiEditor/PlaybackHandler.ts

@@ -135,7 +135,6 @@ export default class MIDIEditorPlaybackHandler {
    * to determine if a given playback session has ended or not.
    */
   private playbackGeneration: number | null = null;
-  private lastPlaybackStartBeat = 0;
   private cbs: {
     start: (startBeat: number) => void;
     stop: () => void;
@@ -343,28 +342,32 @@ export default class MIDIEditorPlaybackHandler {
         return;
       }
 
+      const firstLoopRemainder = loopLengthBeats - (startBeat % loopLengthBeats);
+      const curSegmentAbsoluteStartBeat =
+        startBeat - (loopLengthBeats - firstLoopRemainder) + loopIx * loopLengthBeats;
+      const curSegmentAbsoluteEndBeat = curSegmentAbsoluteStartBeat + loopLengthBeats;
+
       const insts = get(this.inst.uiManager.instances);
       for (const inst of insts) {
         if (inst.type !== 'midiEditor') {
           continue;
         }
         const instance = inst.instance;
 
-        const offset = loopLengthBeats * loopIx;
         // If we're starting in the middle of a loop on the first loop iteration, filter out notes that
         // start before the starting cursor position
         const notesInRange = this.getNotesInRange(
           instance,
-          loopIx === 0 ? startBeat : 0,
+          loopIx === 0 ? startBeat % loopLengthBeats : 0,
           loopPoint,
-          offset
+          curSegmentAbsoluteStartBeat
         );
 
         this.scheduleNotes(instance, notesInRange);
       }
 
       // Schedule an event before the loop ends to recursively schedule another.
-      const curSegmentAbsoluteEndBeat = loopLengthBeats * (loopIx + 1);
+
       scheduleEventBeats(curSegmentAbsoluteEndBeat - Math.min(1, loopLengthBeats / 2), () =>
         scheduleAnother(loopIx + 1)
       );
@@ -408,7 +411,6 @@ export default class MIDIEditorPlaybackHandler {
       }
     }
 
-    this.lastPlaybackStartBeat = startBeat;
     this.playbackGeneration = Math.random();
     if (this.loopPoint === null) {
       this.scheduleOneshot(startBeat);

src/sequencer/redux.ts

@@ -104,7 +104,7 @@ const reschedule = (state: SequencerReduxState): SequencerReduxState => {
 };
 
 interface SequencerInst extends SequencerReduxInfra {
-  onGlobalStart: () => void;
+  onGlobalStart: (startBeat: number) => void;
   onGlobalStop: () => void;
 }
 
@@ -173,8 +173,12 @@ const actionGroups = {
       }),
   }),
   TOGGLE_IS_PLAYING: buildActionGroup({
-    actionCreator: (vcId: string) => ({ type: 'TOGGLE_IS_PLAYING', vcId }),
-    subReducer: (state: SequencerReduxState, { vcId }) => {
+    actionCreator: (vcId: string, startBeat?: number) => ({
+      type: 'TOGGLE_IS_PLAYING',
+      vcId,
+      startBeat,
+    }),
+    subReducer: (state: SequencerReduxState, { vcId, startBeat }) => {
       if (!state.awpHandle) {
         return state;
       }
@@ -185,7 +189,7 @@ const actionGroups = {
         state.awpHandle.port.postMessage({ type: 'stop' });
         return { ...state, isPlaying: false, curActiveMarkIx: null };
       } else {
-        state.awpHandle.port.postMessage({ type: 'start' });
+        state.awpHandle.port.postMessage({ type: 'start', startBeat: startBeat ?? 0 });
         return reschedule({
           ...state,
           isPlaying: true,

src/sequencer/sequencer.tsx

@@ -329,12 +329,12 @@ export const init_sequencer = (stateKey: string) => {
     console.error(`Existing entry in sequencer redux infra map for vcId ${vcId}; overwriting...`);
   }
 
-  const onGlobalStart = () => {
+  const onGlobalStart = (startBeat: number) => {
     const isPlaying = reduxInfra.getState().sequencer.isPlaying;
     if (isPlaying) {
       reduxInfra.dispatch(reduxInfra.actionCreators.sequencer.TOGGLE_IS_PLAYING(vcId));
     }
-    reduxInfra.dispatch(reduxInfra.actionCreators.sequencer.TOGGLE_IS_PLAYING(vcId));
+    reduxInfra.dispatch(reduxInfra.actionCreators.sequencer.TOGGLE_IS_PLAYING(vcId, startBeat));
   };
   registerGlobalStartCB(onGlobalStart);
   const onGlobalStop = () => {