Piano: Use a real transport in the TrackManager

This is technically only a stepping stone but needed to happen at some
point anyways. Now, there's no more integer time stored in Piano's
legacy datastructures directly.

Userland/Applications/Piano/AudioPlayerLoop.cpp

@@ -64,7 +64,7 @@ void AudioPlayerLoop::enqueue_audio()
         do {
             m_track_manager.fill_buffer(m_buffer);
             m_wav_writer.write_samples(reinterpret_cast<u8*>(m_buffer.data()), buffer_size);
-        } while (m_track_manager.time());
+        } while (m_track_manager.transport()->time());
         m_track_manager.reset();
         m_track_manager.set_should_loop(true);
         m_wav_writer.finalize();

Userland/Applications/Piano/RollWidget.cpp

@@ -160,7 +160,7 @@ void RollWidget::paint_event(GUI::PaintEvent& event)
             painter.draw_text(note_name_rect, String::formatted("{}", note / notes_per_octave + 1), Gfx::TextAlignment::CenterLeft);
     }
 
-    int x = m_roll_width * (static_cast<double>(m_track_manager.time()) / roll_length);
+    int x = m_roll_width * (static_cast<double>(m_track_manager.transport()->time()) / roll_length);
     if (x > x_offset && x <= x_offset + widget_inner_rect().width())
         painter.draw_line({ x, 0 }, { x, roll_height }, Gfx::Color::Black);
 

Userland/Applications/Piano/Track.cpp

@@ -16,29 +16,26 @@
 #include <LibDSP/Music.h>
 #include <math.h>
 
-Track::Track(u32 const& time)
-    : m_time(time)
-    , m_temporary_transport(make_ref_counted<LibDSP::Transport>(120, 4))
-    , m_delay(make_ref_counted<LibDSP::Effects::Delay>(m_temporary_transport))
-    , m_synth(make_ref_counted<LibDSP::Synthesizers::Classic>(m_temporary_transport))
+Track::Track(NonnullRefPtr<LibDSP::Transport> transport)
+    : m_transport(move(transport))
+    , m_delay(make_ref_counted<LibDSP::Effects::Delay>(m_transport))
+    , m_synth(make_ref_counted<LibDSP::Synthesizers::Classic>(m_transport))
 {
     set_volume(volume_max);
 }
 
 void Track::fill_sample(Sample& sample)
 {
-    m_temporary_transport->set_time(m_time);
-
     auto playing_notes = LibDSP::RollNotes {};
 
     for (size_t i = 0; i < note_count; ++i) {
         auto& notes_at_pitch = m_roll_notes[i];
         for (auto& note : notes_at_pitch) {
-            if (note.is_playing(m_time))
+            if (note.is_playing(m_transport->time()))
                 playing_notes.set(i, note);
         }
         auto& key_at_pitch = m_keyboard_notes[i];
-        if (key_at_pitch.has_value() && key_at_pitch.value().is_playing(m_time))
+        if (key_at_pitch.has_value() && key_at_pitch.value().is_playing(m_transport->time()))
             playing_notes.set(i, key_at_pitch.value());
         // No need to keep non-playing keyboard notes around.
         else
@@ -70,7 +67,7 @@ void Track::reset()
 
 void Track::sync_roll(int note)
 {
-    auto it = m_roll_notes[note].find_if([&](auto& roll_note) { return roll_note.off_sample > m_time; });
+    auto it = m_roll_notes[note].find_if([&](auto& roll_note) { return roll_note.off_sample > m_transport->time(); });
     if (it.is_end())
         m_roll_iterators[note] = m_roll_notes[note].begin();
     else
@@ -115,15 +112,15 @@ void Track::set_keyboard_note(int note, Switch state)
         // If the note is playing, we need to start releasing it, otherwise just delete
         if (auto& maybe_roll_note = m_keyboard_notes[note]; maybe_roll_note.has_value()) {
             auto& roll_note = maybe_roll_note.value();
-            if (roll_note.is_playing(m_time))
-                roll_note.off_sample = m_time;
+            if (roll_note.is_playing(m_transport->time()))
+                roll_note.off_sample = m_transport->time();
             else
                 m_keyboard_notes[note] = {};
         }
     } else
         // FIXME: The end time needs to be far in the future.
         m_keyboard_notes[note]
-            = RollNote { m_time, m_time + static_cast<u32>(sample_rate) * 10'000, static_cast<u8>(note), 0 };
+            = RollNote { m_transport->time(), m_transport->time() + static_cast<u32>(sample_rate) * 10'000, static_cast<u8>(note), 0 };
 }
 
 void Track::set_volume(int volume)

Userland/Applications/Piano/Track.h

@@ -16,6 +16,7 @@
 #include <LibDSP/Effects.h>
 #include <LibDSP/Music.h>
 #include <LibDSP/Synthesizers.h>
+#include <LibDSP/Transport.h>
 
 using LibDSP::RollNote;
 using RollIter = AK::SinglyLinkedListIterator<SinglyLinkedList<RollNote>, RollNote>;
@@ -25,7 +26,7 @@ class Track {
     AK_MAKE_NONMOVABLE(Track);
 
 public:
-    explicit Track(u32 const& time);
+    Track(NonnullRefPtr<LibDSP::Transport>);
     ~Track() = default;
 
     Vector<Audio::Sample> const& recorded_sample() const { return m_recorded_sample; }
@@ -50,9 +51,7 @@ private:
 
     int m_volume;
 
-    u32 const& m_time;
-
-    NonnullRefPtr<LibDSP::Transport> m_temporary_transport;
+    NonnullRefPtr<LibDSP::Transport> m_transport;
     NonnullRefPtr<LibDSP::Effects::Delay> m_delay;
     NonnullRefPtr<LibDSP::Synthesizers::Classic> m_synth;
 

Userland/Applications/Piano/TrackManager.cpp

@@ -9,20 +9,22 @@
 
 #include "TrackManager.h"
 #include "Applications/Piano/Music.h"
+#include <AK/NonnullRefPtr.h>
 
 TrackManager::TrackManager()
+    : m_transport(make_ref_counted<LibDSP::Transport>(120, 4))
 {
     add_track();
 }
 
 void TrackManager::time_forward(int amount)
 {
-    int new_value = (static_cast<int>(m_time) + amount) % roll_length;
+    int new_value = (static_cast<int>(m_transport->time()) + amount) % roll_length;
 
     if (new_value < 0) { // If the new time value is negative add roll_length to wrap around
-        m_time = roll_length + new_value;
+        m_transport->set_time(roll_length + new_value);
     } else {
-        m_time = new_value;
+        m_transport->set_time(new_value);
     }
 }
 
@@ -34,8 +36,10 @@ void TrackManager::fill_buffer(Span<Sample> buffer)
         for (auto& track : m_tracks)
             track->fill_sample(buffer[i]);
 
-        if (++m_time >= roll_length) {
-            m_time = 0;
+        m_transport->set_time(m_transport->time() + 1);
+        // FIXME: This should be handled automatically by Transport.
+        if (m_transport->time() >= roll_length) {
+            m_transport->set_time(0);
             if (!m_should_loop)
                 break;
         }
@@ -53,7 +57,7 @@ void TrackManager::reset()
     m_current_front_buffer = m_front_buffer.span();
     m_current_back_buffer = m_back_buffer.span();
 
-    m_time = 0;
+    m_transport->set_time(0);
 
     for (auto& track : m_tracks)
         track->reset();
@@ -84,7 +88,7 @@ void TrackManager::set_octave(int octave)
 
 void TrackManager::add_track()
 {
-    m_tracks.append(make<Track>(m_time));
+    m_tracks.append(make<Track>(m_transport));
 }
 
 int TrackManager::next_track_index()

Userland/Applications/Piano/TrackManager.h

@@ -35,7 +35,8 @@ public:
         m_current_track = track_index;
     }
 
-    int time() const { return m_time; }
+    NonnullRefPtr<LibDSP::Transport> transport() const { return m_transport; }
+    // Legacy API, do not add new users.
     void time_forward(int amount);
 
     void fill_buffer(Span<Sample>);
@@ -58,7 +59,7 @@ private:
 
     int m_octave { 4 };
 
-    u32 m_time { 0 };
+    NonnullRefPtr<LibDSP::Transport> m_transport;
 
     bool m_should_loop { true };
 };