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git-svn-id: svn://localhost/ardour2/trunk@1837 d708f5d6-7413-0410-9779-e7cbd77b26cf

libs/ardour/ardour/audio_diskstream.h

@@ -192,7 +192,8 @@ class AudioDiskstream : public Diskstream
 	    
 	    boost::shared_ptr<AudioFileSource> fades_source;
 	    boost::shared_ptr<AudioFileSource> write_source;
-	    
+
+	    /// the Port that our audio data comes from
 	    Port         *source;
 	    Sample       *current_capture_buffer;
 	    Sample       *current_playback_buffer;

libs/ardour/ardour/audioengine.h

@@ -194,24 +194,27 @@ class AudioEngine : public sigc::trackable
 	std::string make_port_name_non_relative (std::string);
 
   private:
-	ARDOUR::Session      *session;
-	jack_client_t       *_jack;
-	std::string           jack_client_name;
-	Glib::Mutex           _process_lock;
-	Glib::Cond            session_removed;
-	bool                  session_remove_pending;
-	bool                 _running;
-	bool                 _has_run;
-	nframes_t       _buffer_size;
-	nframes_t       _frame_rate;
-	nframes_t        monitor_check_interval;
-	nframes_t        last_monitor_check;
-	nframes_t       _processed_frames;
-	bool                 _freewheeling;
-	bool                 _freewheel_thread_registered;
-	sigc::slot<int,nframes_t>  freewheel_action;
-	bool                  reconnect_on_halt;
-	int                  _usecs_per_cycle;
+	ARDOUR::Session *session;
+	jack_client_t *_jack;
+	std::string jack_client_name;
+	Glib::Mutex _process_lock;
+	Glib::Cond session_removed;
+	bool session_remove_pending;
+	bool _running;
+	bool _has_run;
+	nframes_t _buffer_size;
+	nframes_t _frame_rate;
+	/// number of frames between each check for changes in monitor input
+	nframes_t monitor_check_interval;
+	/// time of the last monitor check in frames
+	nframes_t last_monitor_check;
+	/// the number of frames processed since start() was called
+	nframes_t _processed_frames;
+	bool _freewheeling;
+	bool _freewheel_thread_registered;
+	sigc::slot<int,nframes_t> freewheel_action;
+	bool reconnect_on_halt;
+	int _usecs_per_cycle;
 
 	SerializedRCUManager<Ports> ports;
 

libs/ardour/ardour/session.h

@@ -762,6 +762,9 @@ class Session : public PBD::StatefulDestructible
 
 	/* History (for editors, mixers, UIs etc.) */
 
+	/** Undo some transactions.
+	 * @param n Number of transactions to undo.
+	 */
 	void undo (uint32_t n) {
 		_history.undo (n);
 	}
@@ -983,6 +986,7 @@ class Session : public PBD::StatefulDestructible
 
 	AudioEngine            &_engine;
 	mutable gint            processing_prohibited;
+	/// the function called when the main JACK process callback happens
 	process_function_type    process_function;
 	process_function_type    last_process_function;
 	bool                     waiting_for_sync_offset;

libs/ardour/audio_diskstream.cc

@@ -551,7 +551,7 @@ AudioDiskstream::process (nframes_t transport_frame, nframes_t nframes, nframes_
 
 	for (chan = c->begin(); chan != c->end(); ++chan) {
 		(*chan)->current_capture_buffer = 0;
-		(*chan)->current_playback_buffer  = 0;
+		(*chan)->current_playback_buffer = 0;
 	}
 
 	if (nominally_recording || (_session.get_record_enabled() && Config->get_punch_in())) {

libs/ardour/audioengine.cc

@@ -255,6 +255,11 @@ AudioEngine::_graph_order_callback (void *arg)
 	return 0;
 }
 
+/** Wrapped which is called by JACK as its process callback.  It is just
+ * here to get us back into C++ land by calling AudioEngine::process_callback()
+ * @param nframes Number of frames passed by JACK.
+ * @param arg User argument passed by JACK, which will be the AudioEngine*.
+ */
 int
 AudioEngine::_process_callback (nframes_t nframes, void *arg)
 {
@@ -267,11 +272,17 @@ AudioEngine::_freewheel_callback (int onoff, void *arg)
 	static_cast<AudioEngine*>(arg)->_freewheeling = onoff;
 }
 
+/** Method called by JACK (via _process_callback) which says that there
+ * is work to be done.
+ * @param nframes Number of frames to process.
+ */
 int
 AudioEngine::process_callback (nframes_t nframes)
 {
 	// CycleTimer ct ("AudioEngine::process");
 	Glib::Mutex::Lock tm (_process_lock, Glib::TRY_LOCK);
+
+	/// The number of frames that will have been processed when we've finished
 	nframes_t next_processed_frames;
 	
 	/* handle wrap around of total frames counter */
@@ -281,13 +292,15 @@ AudioEngine::process_callback (nframes_t nframes)
 	} else {
 		next_processed_frames = _processed_frames + nframes;
 	}
-	
+
 	if (!tm.locked() || session == 0) {
+		/* return having done nothing */
 		_processed_frames = next_processed_frames;
 		return 0;
 	}
 
 	if (session_remove_pending) {
+		/* perform the actual session removal */
 		session = 0;
 		session_remove_pending = false;
 		session_removed.signal();
@@ -296,6 +309,7 @@ AudioEngine::process_callback (nframes_t nframes)
 	}
 
 	if (_freewheeling) {
+		/* emit the Freewheel signal and stop freewheeling in the event of trouble */
 		if (Freewheel (nframes)) {
 			cerr << "Freewheeling returned non-zero!\n";
 			_freewheeling = false;

libs/ardour/session_process.cc

@@ -44,6 +44,9 @@ using namespace ARDOUR;
 using namespace PBD;
 using namespace std;
 
+/** Called by the audio engine when there is work to be done with JACK.
+ * @param nframes Number of frames to process.
+ */
 void
 Session::process (nframes_t nframes)
 {
@@ -255,7 +258,7 @@ Session::commit_diskstreams (nframes_t nframes, bool &needs_butler)
 	}
 }
 
-
+/** Process callback used when the auditioner is not active */
 void
 Session::process_with_events (nframes_t nframes)
 {
@@ -354,6 +357,8 @@ Session::process_with_events (nframes_t nframes)
 
 		offset = 0;
 
+		/* yes folks, here it is, the actual loop where we really truly
+		   process some audio */
 		while (nframes) {
 
 			this_nframes = nframes; /* real (jack) time relative */
@@ -804,6 +809,9 @@ Session::process_without_events (nframes_t nframes)
 		summon_butler ();
 }
 
+/** Process callback used when the auditioner is active.
+ * @param nframes number of frames to process.
+ */
 void
 Session::process_audition (nframes_t nframes)
 {
@@ -840,6 +848,7 @@ Session::process_audition (nframes_t nframes)
 	}
 
 	if (!auditioner->active()) {
+		/* auditioner no longer active, so go back to the normal process callback */
 		process_function = &Session::process_with_events;
 	}
 }

libs/ardour/session_transport.cc

@@ -718,6 +718,10 @@ Session::locate (nframes_t target_frame, bool with_roll, bool with_flush, bool w
 	_send_smpte_update = true;
 }
 
+/** Set the transport speed.
+ * @param speed New speed
+ * @param abort
+ */
 void
 Session::set_transport_speed (float speed, bool abort)
 {
@@ -733,6 +737,8 @@ Session::set_transport_speed (float speed, bool abort)
 
 	if (transport_rolling() && speed == 0.0) {
 
+		/* we are rolling and we want to stop */
+
 		if (Config->get_monitoring_model() == HardwareMonitoring)
 		{
 			boost::shared_ptr<DiskstreamList> dsl = diskstreams.reader();
@@ -753,6 +759,8 @@ Session::set_transport_speed (float speed, bool abort)
 		
 	} else if (transport_stopped() && speed == 1.0) {
 
+		/* we are stopped and we want to start rolling at speed 1 */
+
 		if (!get_record_enabled() && Config->get_stop_at_session_end() && _transport_frame >= current_end_frame()) {
 			return;
 		}
@@ -825,6 +833,8 @@ Session::set_transport_speed (float speed, bool abort)
 	}
 }
 
+
+/** Stop the transport.  */
 void
 Session::stop_transport (bool abort)
 {

libs/pbd/undo.cc

@@ -174,6 +174,9 @@ UndoHistory::remove (UndoTransaction* const ut)
 	Changed (); /* EMIT SIGNAL */
 }
 
+/** Undo some transactions.
+ * @param n Number of transactions to undo.
+ */
 void
 UndoHistory::undo (unsigned int n)
 {