wip: correct cycle timings (jitter eats notes)

src/main.rs

@@ -237,17 +237,23 @@ process!(App |self, _client, scope| {
     }
     self.playing  = Some(transport.state);
     self.playhead = transport.pos.frame() as usize;
-    let frame  = scope.last_frame_time() as usize;
     let frames = scope.n_frames() as usize;
+    let CycleTimes {
+        current_frames,
+        current_usecs,
+        next_usecs,
+        period_usecs
+    } = scope.cycle_times().unwrap();
     for track in self.tracks.iter_mut() {
         track.process(
             self.midi_in.as_ref().unwrap().iter(scope),
             &self.timebase,
             self.playing,
-            &scope,
-            self.playhead,
-            frames,
             panic,
+            &scope,
+            (current_frames as usize, frames),
+            (current_usecs as usize, next_usecs.saturating_sub(current_usecs) as usize),
+            period_usecs as f64
         );
     }
     Control::Continue