add new (fast) redisplay timer that pushes parameter display text to MCP device.

Changes are queued in a FIFO, and pulled when a timeout in the MCP event loop fires.

5 files changed, 94 insertions, 14 deletions

diff --git a/libs/surfaces/mackie/mackie_control_protocol.cc b/libs/surfaces/mackie/mackie_control_protocol.cc
index d52deb115c..1b66528754 100644
--- a/libs/surfaces/mackie/mackie_control_protocol.cc
+++ b/libs/surfaces/mackie/mackie_control_protocol.cc
@@ -421,7 +421,13 @@ MackieControlProtocol::set_active (bool yn)
 		Glib::RefPtr<Glib::TimeoutSource> periodic_timeout = Glib::TimeoutSource::create (100); // milliseconds
 		periodic_connection = periodic_timeout->connect (sigc::mem_fun (*this, &MackieControlProtocol::periodic));
 		periodic_timeout->attach (main_loop()->get_context());
+
+		/* a faster periodic task used to display parameter updates */
 		
+		Glib::RefPtr<Glib::TimeoutSource> redisplay_timeout = Glib::TimeoutSource::create (10); // milliseconds
+		redisplay_connection = redisplay_timeout->connect (sigc::mem_fun (*this, &MackieControlProtocol::redisplay));
+		redisplay_timeout->attach (main_loop()->get_context());
+
 	} else {
 
 		BaseUI::quit ();
@@ -471,6 +477,33 @@ MackieControlProtocol::periodic ()
 	return true;
 }
 
+bool
+MackieControlProtocol::redisplay ()
+{
+	if (!active()) {
+		return false;
+	}
+
+	if (needs_ipmidi_restart) {
+		ipmidi_restart ();
+		return true;
+	}
+
+	if (!_initialized) {
+		initialize();
+	}
+
+	{
+		Glib::Threads::Mutex::Lock lm (surfaces_lock);
+
+		for (Surfaces::iterator s = surfaces.begin(); s != surfaces.end(); ++s) {
+			(*s)->redisplay ();
+		}
+	}
+
+	return true;
+}
+
 void 
 MackieControlProtocol::update_timecode_beats_led()
 {
@@ -1244,7 +1277,7 @@ void
 MackieControlProtocol::handle_button_event (Surface& surface, Button& button, ButtonState bs)
 {
 	Button::ID button_id = button.bid();
-	
+
 	if  (bs != press && bs != release) {
 		update_led (surface, button, none);
 		return;
@@ -1258,9 +1291,9 @@ MackieControlProtocol::handle_button_event (Surface& surface, Button& button, Bu
 	string action = _device_profile.get_button_action (button.bid(), _modifier_state);
 
 	if (!action.empty()) {
-	
+
 		if (action.find ('/') != string::npos) { /* good chance that this is really an action */
-			
+
 			DEBUG_TRACE (DEBUG::MackieControl, string_compose ("Looked up action for button %1 with modifier %2, got [%3]\n",
 			                                                   button.bid(), _modifier_state, action));
 			
@@ -1273,7 +1306,9 @@ MackieControlProtocol::handle_button_event (Surface& surface, Button& button, Bu
 				DEBUG_TRACE (DEBUG::MackieControl, string_compose ("executing action %1\n", action));
 				access_action (action);
 			}
+
 			return;
+
 		} else {
 			
 			/* "action" is more likely to be a button name. We use this to
diff --git a/libs/surfaces/mackie/mackie_control_protocol.h b/libs/surfaces/mackie/mackie_control_protocol.h
index 140fdd8996..2008d9c887 100644
--- a/libs/surfaces/mackie/mackie_control_protocol.h
+++ b/libs/surfaces/mackie/mackie_control_protocol.h
@@ -281,6 +281,7 @@ class MackieControlProtocol
 	Mackie::DeviceInfo       _device_info;
 	Mackie::DeviceProfile    _device_profile;
 	sigc::connection          periodic_connection;
+	sigc::connection          redisplay_connection;
 	uint32_t                 _current_initial_bank;
 	PBD::ScopedConnectionList audio_engine_connections;
 	PBD::ScopedConnectionList session_connections;
@@ -322,6 +323,7 @@ class MackieControlProtocol
 
 	int create_surfaces ();
 	bool periodic();
+	bool redisplay();
 	void build_gui ();
 	bool midi_input_handler (Glib::IOCondition ioc, MIDI::Port* port);
 	void clear_ports ();
diff --git a/libs/surfaces/mackie/strip.cc b/libs/surfaces/mackie/strip.cc
index 9447b4121c..68978b3de9 100644
--- a/libs/surfaces/mackie/strip.cc
+++ b/libs/surfaces/mackie/strip.cc
@@ -96,6 +96,7 @@ Strip::Strip (Surface& s, const std::string& name, int index, const map<Button::
 	, _last_gain_position_written (-1.0)
 	, _last_pan_azi_position_written (-1.0)
 	, _last_pan_width_position_written (-1.0)
+	, redisplay_requests (256)
 {
 	_fader = dynamic_cast<Fader*> (Fader::factory (*_surface, index, "fader", *this));
 	_vpot = dynamic_cast<Pot*> (Pot::factory (*_surface, Pot::ID + index, "vpot", *this));
@@ -318,18 +319,19 @@ Strip::notify_gain_changed (bool force_update)
 		float gain_coefficient = ac->get_value();
 		float normalized_position = ac->internal_to_interface (gain_coefficient);
 
+
 		if (force_update || normalized_position != _last_gain_position_written) {
 			
 			if (_surface->mcp().flip_mode() != MackieControlProtocol::Normal) {
 				if (!control->in_use()) {
 					_surface->write (_vpot->set (normalized_position, true, Pot::wrap));
 				}
-				do_parameter_display (GainAutomation, gain_coefficient);
+				queue_parameter_display (GainAutomation, gain_coefficient);
 			} else {
 				if (!control->in_use()) {
 					_surface->write (_fader->set_position (normalized_position));
 				}
-				do_parameter_display (GainAutomation, gain_coefficient);
+				queue_parameter_display (GainAutomation, gain_coefficient);
 			}
 
 			queue_display_reset (2000);
@@ -391,7 +393,7 @@ Strip::notify_panner_azi_changed (bool force_update)
 				_surface->write (_vpot->set (pos, true, Pot::dot));
 			}
 			
-			do_parameter_display (PanAzimuthAutomation, pos);
+			queue_parameter_display (PanAzimuthAutomation, pos);
 			queue_display_reset (2000);
 			_last_pan_azi_position_written = pos;
 		}
@@ -435,7 +437,7 @@ Strip::notify_panner_width_changed (bool force_update)
 				_surface->write (_vpot->set (pos, true, Pot::spread));
 			}
 			
-			do_parameter_display (PanWidthAutomation, pos);
+			queue_parameter_display (PanWidthAutomation, pos);
 			queue_display_reset (2000);
 			_last_pan_azi_position_written = pos;
 		}
@@ -512,17 +514,17 @@ Strip::fader_touch_event (Button&, ButtonState bs)
 
 		boost::shared_ptr<AutomationControl> ac = _fader->control ();
 
-		if (_surface->mcp().modifier_state() == MackieControlProtocol::MODIFIER_SHIFT) {
+		if (_surface->mcp().main_modifier_state() & MackieControlProtocol::MODIFIER_SHIFT) {
 			if (ac) {
 				ac->set_value (ac->normal());
 			}
 		} else {
-		
+
 			_fader->set_in_use (true);
 			_fader->start_touch (_surface->mcp().transport_frame());
 			
 			if (ac) {
-				do_parameter_display ((AutomationType) ac->parameter().type(), ac->internal_to_interface (ac->get_value()));
+				queue_parameter_display ((AutomationType) ac->parameter().type(), ac->internal_to_interface (ac->get_value()));
 				queue_display_reset (2000);
 			}
 		}
@@ -605,6 +607,17 @@ Strip::handle_button (Button& button, ButtonState bs)
 }
 
 void
+Strip::queue_parameter_display (AutomationType type, float val)
+{
+	RedisplayRequest req;
+
+	req.type = type;
+	req.val = val;
+
+	redisplay_requests.write (&req, 1);
+}
+
+void
 Strip::do_parameter_display (AutomationType type, float val)
 {
 	switch (type) {
@@ -658,11 +671,16 @@ Strip::handle_fader (Fader& fader, float position)
 	DEBUG_TRACE (DEBUG::MackieControl, string_compose ("fader to %1\n", position));
 
 	fader.set_value (position);
-	queue_display_reset (2000);
 
-	// must echo bytes back to slider now, because
-	// the notifier only works if the fader is not being
-	// touched. Which it is if we're getting input.
+	/* From the Mackie Control MIDI implementation docs:
+
+	   In order to ensure absolute synchronization with the host software,
+	   Mackie Control uses a closed-loop servo system for the faders,
+	   meaning the faders will always move to their last received position.
+	   When a host receives a Fader Position Message, it must then
+	   re-transmit that message to the Mackie Control or else the faders
+	   will return to their last position.
+	*/
 
 	_surface->write (fader.set_position (position));
 }
@@ -697,6 +715,22 @@ Strip::periodic (uint64_t usecs)
 	}
 }
 
+void
+Strip::redisplay ()
+{
+	RedisplayRequest req;
+	bool have_request = false;
+
+	while (redisplay_requests.read (&req, 1) == 1) {
+		/* read them all */
+		have_request = true;
+	}
+
+	if (have_request) {
+		do_parameter_display (req.type, req.val);
+	}
+}
+
 void 
 Strip::update_automation ()
 {
diff --git a/libs/surfaces/mackie/surface.cc b/libs/surfaces/mackie/surface.cc
index eb77e32c97..b448a7ca19 100644
--- a/libs/surfaces/mackie/surface.cc
+++ b/libs/surfaces/mackie/surface.cc
@@ -758,6 +758,14 @@ Surface::periodic (uint64_t now_usecs)
 }
 
 void
+Surface::redisplay ()
+{
+	for (Strips::iterator s = strips.begin(); s != strips.end(); ++s) {
+		(*s)->redisplay ();
+	}
+}
+
+void
 Surface::write (const MidiByteArray& data) 
 {
 	if (_active) {
diff --git a/libs/surfaces/mackie/surface.h b/libs/surfaces/mackie/surface.h
index 2473930528..cc9ba58e7f 100644
--- a/libs/surfaces/mackie/surface.h
+++ b/libs/surfaces/mackie/surface.h
@@ -87,6 +87,7 @@ public:
 	const MidiByteArray& sysex_hdr() const;
 
 	void periodic (uint64_t now_usecs);
+	void redisplay ();
 
 	void handle_midi_pitchbend_message (MIDI::Parser&, MIDI::pitchbend_t, uint32_t channel_id);
 	void handle_midi_controller_message (MIDI::Parser&, MIDI::EventTwoBytes*);