--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/Widgets/PanMouseTracker.cpp	Wed Oct 17 19:38:39 2018 +0200
@@ -0,0 +1,55 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ * Copyright (C) 2017-2018 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/>.
+ **/
+
+
+#include "PanMouseTracker.h"
+
+#include <Core/Logging.h>
+
+namespace OrthancStone
+{
+  PanMouseTracker::PanMouseTracker(WorldSceneWidget& that,
+                                   int x,
+                                   int y) :
+    that_(that)
+  {
+    that.GetView().GetPan(originalPanX_, originalPanY_);
+    that.GetView().MapPixelCenterToScene(downX_, downY_, x, y);
+  }
+    
+
+  void PanMouseTracker::Render(CairoContext& context,
+                               double zoom)
+  {
+    throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError);
+  }
+
+
+  void PanMouseTracker::MouseMove(int displayX,
+                                  int displayY,
+                                  double x,
+                                  double y)
+  {
+    ViewportGeometry view = that_.GetView();
+    view.SetPan(originalPanX_ + (x - downX_) * view.GetZoom(),
+                originalPanY_ + (y - downY_) * view.GetZoom());
+    that_.SetView(view);
+  }
+}