[Summary] Implemented master bus use cases for inspector track view

[Details] 1. Made master bus shownable in inspector when no track selected in StereoOut, StereoOut mode has just been enabled, or there is no tracks at all in StereoOut.
2. Made master bus hidden in MultiOut mode in any case.

gtk2_ardour/editor.cc

@@ -64,6 +64,7 @@
 
 #include "ardour/audio_track.h"
 #include "ardour/audioengine.h"
+#include "ardour/engine_state_controller.h"
 #include "ardour/audioregion.h"
 #include "ardour/location.h"
 #include "ardour/profile.h"
@@ -501,7 +502,9 @@ Editor::Editor ()
 
 	selection->TimeChanged.connect (sigc::mem_fun(*this, &Editor::time_selection_changed));
 	selection->TracksChanged.connect (sigc::mem_fun(*this, &Editor::track_selection_changed));
-
+    
+    EngineStateController::instance()->OutputConnectionModeChanged.connect (*this, invalidator (*this),  boost::bind (&Editor::output_connection_mode_changed, this), gui_context() );
+    
 	editor_regions_selection_changed_connection = selection->RegionsChanged.connect (sigc::mem_fun(*this, &Editor::region_selection_changed));
 
 	selection->PointsChanged.connect (sigc::mem_fun(*this, &Editor::point_selection_changed));
@@ -1385,6 +1388,7 @@ Editor::set_session (Session *t)
 	ActionManager::ui_manager->signal_pre_activate().connect (sigc::mem_fun (*this, &Editor::action_pre_activated));
 
 	start_updating_meters ();
+    
 }
 
 void
@@ -5089,8 +5093,11 @@ Editor::add_routes (RouteList& routes)
 	for (RouteList::iterator x = routes.begin(); x != routes.end(); ++x) {
 		boost::shared_ptr<Route> route = (*x);
 
+        bool is_master_visible = (Config->get_output_auto_connect() & AutoConnectMaster);
+        
 		if (route->is_auditioner() || route->is_monitor() ||
-			!boost::dynamic_pointer_cast<Track> (route)) {
+			(!boost::dynamic_pointer_cast<Track> (route) &&
+             (route->is_master() && !is_master_visible ) ) ) {
 			continue;
 		}
 
@@ -5187,7 +5194,7 @@ Editor::timeaxisview_deleted (TimeAxisView *tv)
 		}
 
 
-		if (next_tv) {
+		if (next_tv ) {
 			set_selected_mixer_strip (*next_tv);
 		} else {
 			/* make the editor mixer strip go away setting the
@@ -5763,3 +5770,28 @@ Editor::zoom_vertical_modifier_released()
 {
 	_stepping_axis_view = 0;
 }
+
+void
+Editor::output_connection_mode_changed ()
+{
+    if (!_session) {
+        return;
+    }
+    
+    if (Config->get_output_auto_connect() & AutoConnectMaster) {
+        
+        if (_session->master_out() && !axis_view_from_route(_session->master_out() ) ) {
+            RouteList list;
+            list.push_back(_session->master_out() );
+            add_routes(list);
+        }
+    } else {
+        TimeAxisView* tv = 0;
+        if (_session->master_out() && (tv = axis_view_from_route(_session->master_out() ) ) ) {
+            delete tv;
+        }
+    }
+    
+    track_selection_changed ();
+}
+

gtk2_ardour/editor.h

@@ -1694,6 +1694,7 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	void time_selection_changed ();
         void update_time_selection_display ();
 	void track_selection_changed ();
+    void output_connection_mode_changed ();
 	void region_selection_changed ();
 	sigc::connection editor_regions_selection_changed_connection;
 	void sensitize_all_region_actions (bool);

gtk2_ardour/editor_mixer.cc

@@ -49,6 +49,7 @@
 using namespace std;
 using namespace Gtkmm2ext;
 using namespace PBD;
+using namespace ARDOUR;
 
 void
 Editor::editor_mixer_button_toggled ()
@@ -108,14 +109,24 @@ Editor::show_editor_mixer (bool yn)
 				return;
 			}
 
-			for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
-				RouteTimeAxisView* atv;
-
-				if ((atv = dynamic_cast<RouteTimeAxisView*> (*i)) != 0) {
+            // check if master is available: try to find it's view
+            TimeAxisView* tv;
+            if ( tv = axis_view_from_route (_session->master_out() ) ) {
+                RouteTimeAxisView* atv = dynamic_cast<RouteTimeAxisView*> (tv);
+                if ( atv != 0 ) {
 					r = atv->route();
-					break;
 				}
-			}
+                
+            } else {
+                // set the first track visible in inspector
+                for (TrackViewList::iterator i = track_views.begin(); i != track_views.end(); ++i) {
+                    RouteTimeAxisView* atv;
+                    if ( atv = dynamic_cast<RouteTimeAxisView*> (*i) ) {
+                        r = atv->route();
+                        break;
+                    }
+                }
+            }
 
 		} else {
 			sort_track_selection (selection->tracks);

gtk2_ardour/editor_selection.cc

@@ -941,13 +941,39 @@ Editor::set_selected_regionview_from_map_event (GdkEventAny* /*ev*/, StreamView*
 void
 Editor::track_selection_changed ()
 {
-	switch (selection->tracks.size()) {
-	case 0:
-		break;
-	default:
-		set_selected_mixer_strip (*(selection->tracks.front()));
-		break;
-	}
+    if (!selection->tracks.empty() ) {
+        set_selected_mixer_strip (*(selection->tracks.front()));
+    } else {
+        // set master bus visible if it's available
+        RouteTimeAxisView* rtv = 0;
+        bool set_master_bus = false;
+        
+        if (_session ) {
+            TimeAxisView* tv = axis_view_from_route (_session->master_out() );
+            rtv = dynamic_cast <RouteTimeAxisView*> (tv);
+            
+            if (rtv) {
+                set_master_bus = true;
+            }
+        }
+        
+        // if master bus is not available (Multi Out mode)
+        if (!set_master_bus && !track_views.empty() ) {
+            
+            TrackViewList::const_iterator iter = track_views.begin();
+            for (; iter != track_views.end() ; ++iter) {
+                
+                if ( ( rtv = dynamic_cast <RouteTimeAxisView*> (*iter ) ) &&
+                     !(rtv->route()->is_master() )) {
+                    break;
+                }
+            }
+        }
+
+        if (rtv) {
+            set_selected_mixer_strip (*rtv );
+        }
+    }
 
 	RouteNotificationListPtr routes (new RouteNotificationList);