Make Model class visitable

src/core/CMakeLists.txt

@@ -40,6 +40,7 @@ set(LMMS_SRCS
 	core/MixerWorkerThread.cpp
 	core/MixHelpers.cpp
 	core/Model.cpp
+	core/ModelVisitor.cpp
 	core/Note.cpp
 	core/NotePlayHandle.cpp
 	core/Oscillator.cpp

src/core/ModelVisitor.cpp

@@ -0,0 +1,28 @@
+/*
+ * ModelVisitor.cpp - visitors for automatable models
+ *
+ * Copyright (c) 2019-2019 Johannes Lorenz <j.git$$$lorenz-ho.me, $$$=@>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#include "ModelVisitor.h"
+
+ModelVisitor::~ModelVisitor() {}
+ConstModelVisitor::~ConstModelVisitor() {}