--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/Scene2D/NullLayer.h	Tue Mar 24 16:24:26 2020 +0100
@@ -0,0 +1,62 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2020 Osimis S.A., Belgium
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 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
+ * Affero General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+#pragma once
+
+#include "ISceneLayer.h"
+
+#include <Core/Enumerations.h>
+
+#include <stdint.h>
+
+/**
+ This layer can be used when a z-index needs to be booked inside a Scene2D.
+
+ It can later be replaced by the actual layer.
+*/
+namespace OrthancStone
+{
+  class NullLayer : public ISceneLayer
+  {
+  public:
+    NullLayer() {}
+
+    virtual ISceneLayer* Clone() const ORTHANC_OVERRIDE
+    {
+      return new NullLayer();
+    }
+
+    virtual Type GetType() const ORTHANC_OVERRIDE
+    {
+      return Type_NullLayer;
+    }
+
+    virtual bool GetBoundingBox(Extent2D& target) const ORTHANC_OVERRIDE
+    {
+      target = Extent2D();
+      return false; 
+    }
+
+    virtual uint64_t GetRevision() const ORTHANC_OVERRIDE
+    {
+      return 0;
+    }
+  };
+}