move logic for use-selection-as-group into ARDOUR_UI and use it everywhere

gtk2_ardour/ardour_ui.h

@@ -399,6 +399,8 @@ public:
 
 	void gui_idle_handler ();
 
+	bool maybe_use_select_as_group (ARDOUR::Route const&) const;
+
 protected:
 	friend class PublicEditor;
 

gtk2_ardour/ardour_ui3.cc

@@ -211,3 +211,29 @@ ARDOUR_UI::record_state_changed ()
 		big_clock->set_active (false);
 	}
 }
+
+bool
+ARDOUR_UI::maybe_use_select_as_group (Route const & route) const
+{
+	if (!UIConfiguration::instance().get_allow_selection_as_group()) {
+		return false;
+	}
+
+	if (!route.is_selected()) {
+		/* Not selected, can't possibly use selection */
+		return false;
+	}
+
+	if (editor->get_selection().tracks.size() < 2) {
+		/* only this track selected */
+		return false;
+	}
+
+	if (route.route_group() && route.route_group()->is_active() && !route.route_group()->is_select()) {
+		/* active route group that does not share selection status */
+		return false;
+	}
+
+	return true;
+}
+

gtk2_ardour/gain_meter.cc

@@ -48,6 +48,7 @@
 
 #include "pbd/fastlog.h"
 
+#include "ardour_ui.h"
 #include "gain_meter.h"
 #include "gui_thread.h"
 #include "keyboard.h"
@@ -757,12 +758,10 @@ GainMeterBase::amp_start_touch (int state)
 {
 	assert (_route);
 
-	if (UIConfiguration::instance().get_allow_selection_as_group()) {
-		if (_route->is_selected() && (!_route->route_group() || !_route->route_group()->is_gain())) {
-			_touch_control_group.reset (new GainControlGroup ());
-			_touch_control_group->set_mode (ControlGroup::Relative);
-			_touch_control_group->fill_from_selection (_control->session().selection(), _control->parameter());
-		}
+	if (ARDOUR_UI::instance()->maybe_use_select_as_group (*_route)) {
+		_touch_control_group.reset (new GainControlGroup ());
+		_touch_control_group->set_mode (ControlGroup::Relative);
+		_touch_control_group->fill_from_selection (_control->session().selection(), _control->parameter());
 	}
 
 	_control->start_touch (timepos_t (_control->session().transport_sample()));

gtk2_ardour/mixer_strip.cc

@@ -73,6 +73,7 @@
 
 #include "widgets/tooltips.h"
 
+#include "ardour_ui.h"
 #include "ardour_window.h"
 #include "automation_controller.h"
 #include "context_menu_helper.h"
@@ -508,7 +509,7 @@ MixerStrip::trim_start_touch (int)
 
 		std::shared_ptr<AutomationControl> control (route()->trim()->gain_control());
 
-		if (maybe_use_select_as_group ()) {
+		if (ARDOUR_UI::instance()->maybe_use_select_as_group (*_route)) {
 			_touch_control_group.reset (new GainControlGroup (TrimAutomation));
 			_touch_control_group->set_mode (ControlGroup::Relative);
 			_touch_control_group->fill_from_selection (control->session().selection(), control->parameter());

gtk2_ardour/route_ui.cc

@@ -566,7 +566,7 @@ RouteUI::mute_press (GdkEventButton* ev)
 				Controllable::GroupControlDisposition gcd;
 				std::shared_ptr<RouteList> rl (new RouteList);
 
-				if (maybe_use_select_as_group ()) {
+				if (ARDOUR_UI::instance()->maybe_use_select_as_group (*_route)) {
 					gather_selected_routes (rl);
 					gcd = Controllable::NoGroup;
 				} else {
@@ -745,7 +745,7 @@ RouteUI::solo_press(GdkEventButton* ev)
 				std::shared_ptr<RouteList> rl (new RouteList);
 				Controllable::GroupControlDisposition gcd;
 
-				if (maybe_use_select_as_group ()) {
+				if (ARDOUR_UI::instance()->maybe_use_select_as_group (*_route)) {
 					gather_selected_routes (rl);
 					gcd = Controllable::NoGroup;
 				} else {
@@ -842,7 +842,7 @@ RouteUI::rec_enable_press(GdkEventButton* ev)
 				Controllable::GroupControlDisposition gcd;
 				rl.reset (new RouteList);
 
-				if (maybe_use_select_as_group ()) {
+				if (ARDOUR_UI::instance()->maybe_use_select_as_group (*_route)) {
 					gather_selected_routes (rl);
 					gcd = Controllable::NoGroup;
 				} else {
@@ -2883,36 +2883,6 @@ RouteUI::rename_current_playlist ()
 	}
 }
 
-bool
-RouteUI::maybe_use_select_as_group () const
-{
-	if (!UIConfiguration::instance().get_allow_selection_as_group()) {
-		return false;
-	}
-
-	if (!route()) {
-		/* Shouldn't happen but protects conditionals below */
-		return false;
-	}
-
-	if (!route()->is_selected()) {
-		/* Not selected, can't possibly use selection */
-		return false;
-	}
-
-	if (ARDOUR_UI::instance()->the_editor().get_selection().tracks.size() < 2) {
-		/* only this track selected */
-		return false;
-	}
-
-	if (route()->route_group() && route()->route_group()->is_active() && !route()->route_group()->is_select()) {
-		/* active route group that does not share selection status */
-		return false;
-	}
-
-	return true;
-}
-
 void
 RouteUI::gather_selected_routes (std::shared_ptr<RouteList>& rl) const
 {

gtk2_ardour/route_ui.h

@@ -263,7 +263,6 @@ protected:
 	ARDOUR::SoloMuteRelease* _solo_release;
 	ARDOUR::SoloMuteRelease* _mute_release;
 
-	bool maybe_use_select_as_group () const;
 	void gather_selected_routes (std::shared_ptr<ARDOUR::RouteList>& rl) const;
 
 private: