From 46315cde5707feabee6487804460e5ebc7a466c6 Mon Sep 17 00:00:00 2001
From: Paul Davis <paul@linuxaudiosystems.com>
Date: Mon, 6 May 2024 16:18:58 -0600
Subject: [PATCH] T: save/restore master send levels across virtual soundcheck
 toggle

---
 libs/ardour/ardour/session.h |  1 +
 libs/ardour/session.cc       | 35 ++++++++++++++++++++++++++++-------
 2 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/libs/ardour/ardour/session.h b/libs/ardour/ardour/session.h
index c5c0fee6ea..058b02b488 100644
--- a/libs/ardour/ardour/session.h
+++ b/libs/ardour/ardour/session.h
@@ -2457,6 +2457,7 @@ private:
 	bool _virtual_soundcheck;
 
 	std::atomic<uint32_t> _no_livetrax_auto_connect;
+	std::map<PBD::ID,double> livetrax_vs_msend_values;
 };
 
 
diff --git a/libs/ardour/session.cc b/libs/ardour/session.cc
index 6745c8aa4a..232a78a092 100644
--- a/libs/ardour/session.cc
+++ b/libs/ardour/session.cc
@@ -8380,9 +8380,7 @@ Session::set_virtual_soundcheck (bool yn)
 	std::shared_ptr<RouteList const> rl = routes.reader ();
 	std::shared_ptr<AutomationControlList> master_sends (new AutomationControlList);
 	std::shared_ptr<AutomationControlList> main_outs (new AutomationControlList);
-
-	gain_t main_val = (yn ? 1. : 0.);
-	gain_t send_val = (yn ? 0. : 1.);
+	std::vector<double> values;
 
 	for (auto & route : *rl) {
 
@@ -8391,14 +8389,37 @@ Session::set_virtual_soundcheck (bool yn)
 		}
 
 		master_sends->push_back (route->master_send()->gain_control());
-		// virtual_soundcheck_msend_values.insert (std::make_pair (route, route->master_send()->gain_control()->get_value()));
 		main_outs->push_back (route->main_outs()->gain_control());
-		// virtual_soundcheck_direct_values.insert (std::make_pair (route, route->main_outs()->gain_control()->get_value()));
+
+		if (yn) {
+			/* Save current values for master send gain before we turn it off */
+			double g = route->master_send()->gain_control()->get_value();
+			auto result = livetrax_vs_msend_values.insert (std::make_pair (route->id(), g));
+			if (!result.second) {
+				result.first->second = g;
+			}
+
+		} else {
+			/* Lookup master send gain values from before we turned them off */
+			std::map<PBD::ID,double>::iterator v = livetrax_vs_msend_values.find (route->id());
+			if (v == livetrax_vs_msend_values.end()) {
+				/* not found - use a default */
+				values.push_back (1.0);
+			} else {
+				values.push_back (v->second);
+			}
+		}
 	}
 
 	if (!master_sends->empty()) {
-		set_controls (master_sends, send_val, PBD::Controllable::NoGroup);
-		set_controls (main_outs, main_val, PBD::Controllable::NoGroup);
+		if (yn) {
+			set_controls (master_sends, 0., PBD::Controllable::NoGroup);
+			set_controls (main_outs, 1., PBD::Controllable::NoGroup);
+		} else {
+			assert (master_sends->size() == values.size());
+			set_controls_with_values (master_sends, values, PBD::Controllable::NoGroup);
+			set_controls (main_outs, 0., PBD::Controllable::NoGroup);
+		}
 	}
 
 	_virtual_soundcheck = yn;