clickless meter-point changes

libs/ardour/session_process.cc

@@ -75,6 +75,17 @@ Session::process (pframes_t nframes)
 
 	(this->*process_function) (nframes);
 
+	/* realtime-safe meter-position changes
+	 *
+	 * ideally this would be done in
+	 * Route::process_output_buffers() but various functions
+	 * callig it hold a _processor_lock reader-lock
+	 */
+	boost::shared_ptr<RouteList> r = routes.reader ();
+	for (RouteList::iterator i = r->begin(); i != r->end(); ++i) {
+		(*i)->apply_meter_change_rt();
+	}
+
 	_engine.main_thread()->drop_buffers ();
 
 	/* deliver MIDI clock. Note that we need to use the transport frame