1 files changed, 54 insertions, 51 deletions

diff --git a/libs/ardour/plugin_insert.cc b/libs/ardour/plugin_insert.cc
index 98ff9ab4f0..ec6d86d71a 100644
--- a/libs/ardour/plugin_insert.cc
+++ b/libs/ardour/plugin_insert.cc
@@ -264,26 +264,53 @@ PluginInsert::create_automatable_parameters ()
 		}
 	}
 }
-
+/** Called when something outside of this host has modified a plugin
+ * parameter. Responsible for propagating the change to two places:
+ *
+ *   1) anything listening to the Control itself
+ *   2) any replicated plugins that make up this PluginInsert.
+ *
+ * The PluginInsert is connected to the ParameterChangedExternally signal for
+ * the first (primary) plugin, and here broadcasts that change to any others.
+ *
+ * XXX We should probably drop this whole replication idea (Paul, October 2015)
+ * since it isn't used by sensible plugin APIs (AU, LV2).
+ */
 void
-PluginInsert::parameter_changed (uint32_t which, float val)
+PluginInsert::parameter_changed_externally (uint32_t which, float val)
 {
 	boost::shared_ptr<AutomationControl> ac = automation_control (Evoral::Parameter (PluginAutomation, 0, which));
 
-	if (ac) {
-		ac->set_value (val);
+	/* First propagation: alter the underlying value of the control,
+	 * without telling the plugin(s) that own/use it to set it.
+	 */
+
+	if (!ac) {
+		return;
+	}
 
-                Plugins::iterator i = _plugins.begin();
+	boost::shared_ptr<PluginControl> pc = boost::dynamic_pointer_cast<PluginControl> (ac);
 
-                /* don't set the first plugin, just all the slaves */
+	if (pc) {
+		pc->catch_up_with_external_value (val);
+	}
 
-                if (i != _plugins.end()) {
-                        ++i;
-                        for (; i != _plugins.end(); ++i) {
-                                (*i)->set_parameter (which, val);
-                        }
-                }
-        }
+	/* Second propagation: tell all plugins except the first to
+	   update the value of this parameter. For sane plugin APIs,
+	   there are no other plugins, so this is a no-op in those
+	   cases.
+	*/
+
+	Plugins::iterator i = _plugins.begin();
+
+	/* don't set the first plugin, just all the slaves */
+
+	if (i != _plugins.end()) {
+		++i;
+		for (; i != _plugins.end(); ++i) {
+			(*i)->set_parameter (which, val);
+		}
+	}
 }
 
 int
@@ -507,41 +534,6 @@ PluginInsert::run (BufferSet& bufs, framepos_t start_frame, framepos_t /*end_fra
 }
 
 void
-PluginInsert::set_parameter (Evoral::Parameter param, float val)
-{
-	if (param.type() != PluginAutomation) {
-		return;
-	}
-
-	/* the others will be set from the event triggered by this */
-
-	_plugins[0]->set_parameter (param.id(), val);
-
-	boost::shared_ptr<AutomationControl> ac
-			= boost::dynamic_pointer_cast<AutomationControl>(control(param));
-
-	if (ac) {
-		ac->set_value(val);
-	} else {
-		warning << "set_parameter called for nonexistent parameter "
-			<< EventTypeMap::instance().to_symbol(param) << endmsg;
-	}
-
-	_session.set_dirty();
-}
-
-float
-PluginInsert::get_parameter (Evoral::Parameter param)
-{
-	if (param.type() != PluginAutomation) {
-		return 0.0;
-	} else {
-		assert (!_plugins.empty ());
-		return _plugins[0]->get_parameter (param.id());
-	}
-}
-
-void
 PluginInsert::automation_run (BufferSet& bufs, framepos_t start, pframes_t nframes)
 {
 	Evoral::ControlEvent next_event (0, 0.0f);
@@ -1317,6 +1309,12 @@ PluginInsert::PluginControl::set_value (double user_val)
 	AutomationControl::set_value (user_val);
 }
 
+void
+PluginInsert::PluginControl::catch_up_with_external_value (double user_val)
+{
+	AutomationControl::set_value (user_val);
+}
+
 XMLNode&
 PluginInsert::PluginControl::get_state ()
 {
@@ -1333,8 +1331,13 @@ PluginInsert::PluginControl::get_state ()
 double
 PluginInsert::PluginControl::get_value () const
 {
-	/* FIXME: probably should be taking out some lock here.. */
-	return _plugin->get_parameter (_list->parameter());
+	boost::shared_ptr<Plugin> plugin = _plugin->plugin (0);
+
+	if (!plugin) {
+		return 0.0;
+	}
+
+	return plugin->get_parameter (_list->parameter().id());
 }
 
 PluginInsert::PluginPropertyControl::PluginPropertyControl (PluginInsert*                     p,
@@ -1430,7 +1433,7 @@ PluginInsert::add_plugin (boost::shared_ptr<Plugin> plugin)
                 /* first (and probably only) plugin instance - connect to relevant signals
                  */
 
-		plugin->ParameterChanged.connect_same_thread (*this, boost::bind (&PluginInsert::parameter_changed, this, _1, _2));
+		plugin->ParameterChangedExternally.connect_same_thread (*this, boost::bind (&PluginInsert::parameter_changed_externally, this, _1, _2));
                 plugin->StartTouch.connect_same_thread (*this, boost::bind (&PluginInsert::start_touch, this, _1));
                 plugin->EndTouch.connect_same_thread (*this, boost::bind (&PluginInsert::end_touch, this, _1));
 	}