- Evoral::Sequence<Evoral::Beats>::const_iterator& i = _model_iter;
- const bool linear_read = _last_read_end != 0 && start == _last_read_end;
- if (!linear_read || !_model_iter_valid) {
-#if 0
- // Cached iterator is invalid, search for the first event past start
- i = _model->begin(converter.from(start), false, filtered,
- linear_read ? &_model->active_notes() : NULL);
- _model_iter_valid = true;
- if (!linear_read) {
- _model->active_notes().clear();
- }
-#else
- /* hot-fix http://tracker.ardour.org/view.php?id=6541
- * "parallel playback of linked midi regions -> no note-offs"
- *
- * A midi source can be used by multiple tracks simultaneously,
- * in which case midi_read() may be called from different tracks for
- * overlapping time-ranges.
- *
- * However there is only a single iterator for a given midi-source.
- * This results in every midi_read() performing a seek.
- *
- * If seeking is performed with
- * _model->begin(converter.from(start),...)
- * the model is used for seeking. That method seeks to the first
- * *note-on* event after 'start'.
- *
- * _model->begin(converter.from( ) ,..) eventually calls
- * Sequence<Time>::const_iterator() in libs/evoral/src/Sequence.cpp
- * which looks up the note-event via seq.note_lower_bound(t);
- * but the sequence 'seq' only contains note-on events(!).
- * note-off events are implicit in Sequence<Time>::operator++()
- * via _active_notes.pop(); and not part of seq.
- *
- * see also http://tracker.ardour.org/view.php?id=6287#c16671
- *
- * The linear search below assures that reading starts at the first
- * event for the given time, regardless of its event-type.
- *
- * The performance of this approach is O(N), while the previous
- * implementation is O(log(N)). This needs to be optimized:
- * The model-iterator or event-sequence needs to be re-designed in
- * some way (maybe keep an iterator per playlist).
- */
- for (i = _model->begin(); i != _model->end(); ++i) {
- if (i->time().to_double() >= start_beats) {
- break;
- }
- }
- _model_iter_valid = true;
- if (!linear_read) {
- _model->active_notes().clear();
- }
-#endif
+ Evoral::Sequence<Evoral::Beats>::const_iterator& i = cursor.iter;
+ const bool linear_read = cursor.last_read_end != 0 && start == cursor.last_read_end;
+ if (!linear_read || !i.valid()) {
+ /* Cached iterator is invalid, search for the first event past start.
+ Note that multiple tracks can use a MidiSource simultaneously, so
+ all playback state must be in parameters (the cursor) and must not
+ be cached in the source of model itself.
+ See http://tracker.ardour.org/view.php?id=6541
+ */
+ cursor.connect(Invalidated);
+ cursor.iter = _model->begin(converter.from(start), false, filtered, &cursor.active_notes);
+ cursor.active_notes.clear();