--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Framework/Toolbox/ViewportGeometry.h	Fri Oct 14 15:34:11 2016 +0200
@@ -0,0 +1,115 @@
+/**
+ * Stone of Orthanc
+ * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
+ * Department, University Hospital of Liege, Belgium
+ *
+ * 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 3 of the
+ * License, or (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders of this
+ * program give permission to link the code of its release with the
+ * OpenSSL project's "OpenSSL" library (or with modified versions of it
+ * that use the same license as the "OpenSSL" library), and distribute
+ * the linked executables. You must obey the GNU General Public License
+ * in all respects for all of the code used other than "OpenSSL". If you
+ * modify file(s) with this exception, you may extend this exception to
+ * your version of the file(s), but you are not obligated to do so. If
+ * you do not wish to do so, delete this exception statement from your
+ * version. If you delete this exception statement from all source files
+ * in the program, then also delete it here.
+ * 
+ * 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. If not, see <http://www.gnu.org/licenses/>.
+ **/
+
+
+#pragma once
+
+#include "../Viewport/CairoContext.h"
+
+namespace OrthancStone
+{
+  // Not thread-safe
+  class ViewportGeometry
+  {
+  private:
+    // Extent of the scene (in world units)
+    double   x1_;
+    double   y1_;
+    double   x2_;
+    double   y2_;
+
+    // Size of the display (in pixels)
+    unsigned int  width_;
+    unsigned int  height_;
+
+    // Zoom/pan
+    double   zoom_;
+    double   panX_;  // In pixels (display units)
+    double   panY_;
+
+    cairo_matrix_t  transform_;  // Scene-to-display transformation
+
+    void ComputeTransform();
+
+  public:
+    ViewportGeometry();
+
+    void SetDisplaySize(unsigned int width,
+                        unsigned int height);
+
+    void SetSceneExtent(double x1,
+                        double y1,
+                        double x2,
+                        double y2);
+
+    void GetSceneExtent(double& x1,
+                        double& y1,
+                        double& x2,
+                        double& y2) const;
+
+    void MapDisplayToScene(double& sceneX /* out */,
+                           double& sceneY /* out */,
+                           double x,
+                           double y) const;
+
+    void MapSceneToDisplay(int& displayX /* out */,
+                           int& displayY /* out */,
+                           double x,
+                           double y) const;
+
+    unsigned int GetDisplayWidth() const
+    {
+      return width_;
+    }
+
+    unsigned int GetDisplayHeight() const
+    {
+      return height_;
+    }
+
+    double GetZoom() const
+    {
+      return zoom_;
+    }
+
+    void SetDefaultView();
+
+    void ApplyTransform(CairoContext& context) const;
+
+    void GetPan(double& x,
+                double& y) const;
+
+    void SetPan(double x,
+                double y);
+
+    void SetZoom(double zoom);
+  };
+}