--- a/CMakeLists.txt	Wed Apr 16 12:12:55 2014 +0200
+++ b/CMakeLists.txt	Wed Apr 16 16:04:55 2014 +0200
@@ -222,6 +222,8 @@
   OrthancServer/ServerToolbox.cpp
   OrthancServer/OrthancFindRequestHandler.cpp
   OrthancServer/OrthancMoveRequestHandler.cpp
+
+  #OrthancServer/RadiotherapyRestApi.cpp
   )
 
 # Ensure autogenerated code is built before building ServerLibrary

--- a/OrthancServer/FromDcmtkBridge.cpp	Wed Apr 16 12:12:55 2014 +0200
+++ b/OrthancServer/FromDcmtkBridge.cpp	Wed Apr 16 16:04:55 2014 +0200
@@ -839,13 +839,13 @@
 
 
 
-  bool ParsedDicomFile::GetTagValue(std::string& value,
-                                    const DicomTag& tag)
+  static bool GetTagValueInternal(std::string& value,
+                                  DcmItem& item,
+                                  const DicomTag& tag)
   {
     DcmTagKey k(tag.GetGroup(), tag.GetElement());
-    DcmDataset& dataset = *file_->getDataset();
     DcmElement* element = NULL;
-    if (!dataset.findAndGetElement(k, element).good() ||
+    if (!item.findAndGetElement(k, element).good() ||
         element == NULL)
     {
       return false;
@@ -862,7 +862,57 @@
       value = v->AsString();
     }
 
-    return true;
+    return true;    
+  }
+
+
+  bool ParsedDicomFile::GetTagValue(std::string& value,
+                                    const DicomTag& tag)
+  {
+    DcmDataset& dataset = *file_->getDataset();
+    return GetTagValueInternal(value, dataset, tag);
+  }
+
+
+
+  bool ParsedDicomFile::GetTagValue(std::string& value,
+                                    const SequencePath& path,
+                                    const DicomTag& tag)
+  {
+    if (path.size() == 0)
+    {
+      return GetTagValue(value, tag);
+    }
+
+    DcmItem* current = file_->getDataset();
+      assert(current != NULL);
+
+    for (SequencePath::const_iterator it = path.begin(); it != path.end(); it++)
+    {
+      DcmTagKey k(it->first.GetGroup(), it->first.GetElement());
+
+      DcmSequenceOfItems* sequence = NULL;
+      if (!current->findAndGetSequence(k, sequence).good() ||
+          sequence == NULL ||
+          sequence->getVR() != EVR_SQ)
+      {
+        return false;
+      }
+
+      if (it->second < 0 || it->second > sequence->card())
+      {
+        return false;
+      }
+
+      current = sequence->getItem(it->second);
+
+      if (current == NULL)
+      {
+        return false;
+      }
+    }
+    
+    return GetTagValueInternal(value, *current, tag);    
   }
 
 

--- a/OrthancServer/FromDcmtkBridge.h	Wed Apr 16 12:12:55 2014 +0200
+++ b/OrthancServer/FromDcmtkBridge.h	Wed Apr 16 16:04:55 2014 +0200
@@ -72,6 +72,8 @@
                size_t size);
 
   public:
+    typedef std::list< std::pair<DicomTag, unsigned int> >  SequencePath;
+
     ParsedDicomFile(const char* content,
                     size_t size)
     {
@@ -115,6 +117,10 @@
     bool GetTagValue(std::string& value,
                      const DicomTag& tag);
 
+    bool GetTagValue(std::string& value,
+                     const SequencePath& path,
+                     const DicomTag& tag);
+
     DicomInstanceHasher GetHasher();
   };
 

--- a/OrthancServer/OrthancRestApi/OrthancRestApi.h	Wed Apr 16 12:12:55 2014 +0200
+++ b/OrthancServer/OrthancRestApi/OrthancRestApi.h	Wed Apr 16 16:04:55 2014 +0200
@@ -44,7 +44,7 @@
   public:
     typedef std::set<std::string> SetOfStrings;
 
-  private:
+  protected:
     ServerContext& context_;
 
     void RegisterSystem();

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancServer/RadiotherapyRestApi.cpp	Wed Apr 16 16:04:55 2014 +0200
@@ -0,0 +1,815 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2013 Medical Physics Department, CHU 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/>.
+ **/
+
+
+#include "RadiotherapyRestApi.h"
+
+#include "ServerToolbox.h"
+
+#define RETRIEVE_CONTEXT(call)                          \
+  OrthancRestApi& contextApi =                          \
+    dynamic_cast<OrthancRestApi&>(call.GetContext());   \
+  ServerContext& context = contextApi.GetContext()
+
+
+// DICOM tags for RT-STRUCT
+
+/**
+ * REFERENCE: http://www.dabsoft.ch/dicom/3/C.8.8.6/
+ *
+ * IMPORTANT: The points/vertices coordinates are reported in [mm]. 
+ * 
+ * TODO: Support "Contour Offset Vector"
+ **/
+
+
+#define REFERENCED_STUDY_SEQUENCE "0008,1110"
+#define REFERENCED_SOP_INSTANCE_UID "0008,1155"
+#define FRAME_OF_REFERENCE_UID "0020,0052"
+#define REFERENCED_FRAME_OF_REFERENCE_SEQUENCE "3006,0010"
+#define STRUCTURE_SET_ROI_SEQUENCE "3006,0020"
+#define ROI_NUMBER "3006,0022"
+#define ROI_NAME "3006,0026"
+#define ROI_GENERATION_ALGORITHM "3006,0036"
+#define ROI_CONTOUR_SEQUENCE "3006,0039"
+#define REFERENCED_ROI_NUMBER "3006,0084"
+#define ROI_DISPLAY_COLOR "3006,002a"
+#define CONTOUR_SEQUENCE "3006,0040"
+#define CONTOUR_IMAGE_SEQUENCE "3006,0016"
+#define CONTOUR_GEOMETRIC_TYPE "3006,0042"
+#define NUMBER_OF_CONTOUR_POINTS "3006,0046"
+#define CONTOUR_DATA "3006,0050"
+#define CONTOUR_SLAB_THICKNESS "3006,0044"
+#define SLICE_THICKNESS "0018,0050"
+
+
+
+#include <boost/geometry.hpp>
+#include <boost/geometry/geometries/point.hpp>
+#include <boost/geometry/geometries/point_xy.hpp>
+#include <boost/geometry/geometries/polygon.hpp>
+#include <boost/geometry/geometries/linestring.hpp>
+
+namespace Orthanc
+{
+  static bool CheckSeriesModality(Json::Value& study,
+                                  Json::Value& series,
+                                  Json::Value& content,
+                                  ServerContext& context,
+                                  const std::string& seriesId,
+                                  const std::string& modality)
+  {
+    if (!context.GetIndex().LookupResource(series, seriesId, ResourceType_Series))
+    {
+      return false;
+    }
+
+    // Retrieve the parent study
+    std::string studyId = series["ParentStudy"].asString();
+    if (!context.GetIndex().LookupResource(study, studyId, ResourceType_Study))
+    {
+      return false;
+    }
+
+    // Check the modality and that there is a single instance inside the series
+    if (!series["MainDicomTags"].isMember("Modality") ||
+        series["MainDicomTags"]["Modality"].asString() != modality ||
+        series["Instances"].size() != 1)
+    {
+      return false;
+    }
+
+    // Retrieve the instance data
+    std::string instanceId = series["Instances"][0].asString();
+
+    context.ReadJson(content, instanceId);
+
+    return true;
+  }
+
+
+  static bool ContourToPoints(Json::Value& result,
+                              const Json::Value& source)
+  {
+    std::vector<std::string> points;
+    Toolbox::Split(points, source.asString(), '\\');
+
+    if (points.size() % 3 != 0)
+    {
+      return false;
+    }
+
+    result = Json::arrayValue;
+
+    for (size_t k = 0; k < points.size(); k += 3)
+    {
+      Json::Value p = Json::arrayValue;
+
+      try
+      {
+        p.append(boost::lexical_cast<float>(points[k]));
+        p.append(boost::lexical_cast<float>(points[k + 1]));
+        p.append(boost::lexical_cast<float>(points[k + 2]));
+      }
+      catch (boost::bad_lexical_cast)
+      {
+        return false;
+      }
+
+      result.append(p);
+    }
+
+    return true;
+  }
+
+
+  static bool GetRtStructuresInfo(Json::Value& study,
+                                  Json::Value& series,
+                                  Json::Value& content,
+                                  std::string& frameOfReference,
+                                  ServerContext& context,
+                                  const std::string& seriesId)
+  {
+    if (!CheckSeriesModality(study, series, content, context, seriesId, "RTSTRUCT"))
+    {
+      return false;
+    }
+
+    // Check that the "ReferencedStudySequence" (if any) is the same as the parent study.
+    if (content.isMember(REFERENCED_STUDY_SEQUENCE))
+    {
+      if (content[REFERENCED_STUDY_SEQUENCE]["Value"].size() != 1 ||
+          !content[REFERENCED_STUDY_SEQUENCE]["Value"][0].isMember(REFERENCED_SOP_INSTANCE_UID) ||
+          content[REFERENCED_STUDY_SEQUENCE]["Value"][0][REFERENCED_SOP_INSTANCE_UID]["Value"].asString() != 
+          study["MainDicomTags"]["StudyInstanceUID"].asString())
+      {
+        return false;
+      }
+    }
+
+    // Lookup for the frame of reference. Orthanc does not support
+    // RTSTRUCT with multiple frames of reference.
+    if (!content.isMember(REFERENCED_FRAME_OF_REFERENCE_SEQUENCE) ||
+        content[REFERENCED_FRAME_OF_REFERENCE_SEQUENCE]["Value"].size() != 1 ||
+        !content[REFERENCED_FRAME_OF_REFERENCE_SEQUENCE]["Value"][0].isMember(FRAME_OF_REFERENCE_UID))
+    {
+      return false;
+    }
+
+    frameOfReference = content[REFERENCED_FRAME_OF_REFERENCE_SEQUENCE]["Value"][0][FRAME_OF_REFERENCE_UID]["Value"].asString();
+
+    return true;
+  }
+
+
+  static bool GetRtStructuresRoi(Json::Value& result,
+                                 Json::Value& contourSequence,
+                                 std::string& instanceId,
+                                 ServerContext& context,
+                                 const std::string& seriesId,
+                                 const std::string& roiNumber)
+  {
+    Json::Value study, series, content;
+    std::string frameOfReference;
+
+    if (!GetRtStructuresInfo(study, series, content, frameOfReference, context, seriesId))
+    {
+      return false;
+    }
+
+    if (!content.isMember(STRUCTURE_SET_ROI_SEQUENCE) ||
+        !content.isMember(ROI_CONTOUR_SEQUENCE))
+    {
+      return false;
+    }
+
+    instanceId = series["Instances"][0].asString();
+
+    bool found = false;
+
+    for (Json::Value::ArrayIndex i = 0; i < content[STRUCTURE_SET_ROI_SEQUENCE]["Value"].size(); i++)
+    {
+      const Json::Value& roi = content[STRUCTURE_SET_ROI_SEQUENCE]["Value"][i];
+
+      if (roi.isMember(ROI_NUMBER) &&
+          roi.isMember(ROI_NAME) &&
+          roi[ROI_NUMBER]["Value"].asString() == roiNumber)
+      {
+        result["InternalIndex"] = i;
+        result["Number"] = boost::lexical_cast<unsigned int>(roiNumber);
+        result["Name"] = roi[ROI_NAME]["Value"].asString();
+        result["GenerationAlgorithm"] = roi[ROI_GENERATION_ALGORITHM]["Value"].asString();
+        found = true;
+      }
+    }
+
+    if (!found)
+    {
+      return false;
+    }
+
+    for (Json::Value::ArrayIndex i = 0; i < content[ROI_CONTOUR_SEQUENCE]["Value"].size(); i++)
+    {
+      const Json::Value& contour = content[ROI_CONTOUR_SEQUENCE]["Value"][i];
+
+      if (contour.isMember(REFERENCED_ROI_NUMBER) &&
+          contour.isMember(ROI_DISPLAY_COLOR) &&
+          contour.isMember(CONTOUR_SEQUENCE) &&
+          contour[REFERENCED_ROI_NUMBER]["Value"].asString() == roiNumber)
+      {
+        std::vector<std::string> color;
+        Toolbox::Split(color, contour[ROI_DISPLAY_COLOR]["Value"].asString(), '\\');
+
+        result["DisplayColor"] = Json::arrayValue;
+        if (color.size() != 3)
+        {
+          return false;
+        }
+
+        for (size_t k = 0; k < color.size(); k++)
+        {
+          try
+          {
+            result["DisplayColor"].append(boost::lexical_cast<int>(color[k]));
+          }
+          catch (boost::bad_lexical_cast)
+          {
+            return false;
+          }
+        }
+
+        contourSequence = contour[CONTOUR_SEQUENCE]["Value"];
+
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+
+  static bool GetClosedPlanarPoints(Json::Value& result,
+                                    ServerContext& context,
+                                    const std::string& instanceId,
+                                    const Json::Value& roi,
+                                    unsigned int index)
+  {
+    boost::mutex::scoped_lock lock(context.GetDicomFileMutex());
+    ParsedDicomFile& dicom = context.GetDicomFile(instanceId);
+
+    ParsedDicomFile::SequencePath path;
+    path.push_back(std::make_pair(DicomTag(0x3006, 0x0039 /* ROIContourSequence */), roi["InternalIndex"].asInt()));
+    path.push_back(std::make_pair(DicomTag(0x3006, 0x0040 /* ContourSequence */), index));
+        
+    std::string contourData;
+    std::string numberOfPoints;
+
+    if (dicom.GetTagValue(contourData, path, DicomTag(0x3006, 0x0050 /* ContourData */)) &&
+        dicom.GetTagValue(numberOfPoints, path, DicomTag(0x3006, 0x0046 /* NumberOfContourPoints */)) &&
+        ContourToPoints(result, contourData) &&
+        result.size() == boost::lexical_cast<unsigned int>(numberOfPoints))
+    {
+      return true;
+    }
+    else
+    {
+      return false;
+    }
+  }
+
+
+
+  static bool LookupReferencedInstance(Json::Value& result,
+                                       ServerContext& context,
+                                       const Json::Value& contour)
+  {
+    if (contour.isMember(CONTOUR_IMAGE_SEQUENCE) &&
+        contour[CONTOUR_IMAGE_SEQUENCE]["Value"].size() == 1 &&
+        contour[CONTOUR_IMAGE_SEQUENCE]["Value"][0].isMember(REFERENCED_SOP_INSTANCE_UID))
+    {
+      std::string uid = contour[CONTOUR_IMAGE_SEQUENCE]["Value"][0][REFERENCED_SOP_INSTANCE_UID]["Value"].asString();
+
+      std::list<std::string> instance;
+      context.GetIndex().LookupTagValue(instance, DICOM_TAG_SOP_INSTANCE_UID, uid);
+
+      if (instance.size() == 1 &&
+          context.GetIndex().LookupResource(result, instance.front(), ResourceType_Instance))
+      {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+
+  static bool GetRtStructuresClosedPlanarThickness(float& result,
+                                                   ServerContext& context,
+                                                   const Json::Value& contour)
+  {
+    if (contour.isMember(CONTOUR_SLAB_THICKNESS))
+    {
+      result = boost::lexical_cast<float>(contour[CONTOUR_SLAB_THICKNESS]["Value"].asString());
+      return true;
+    }
+
+    // No slab thickness is explicitely specified: Fallback to
+    // the thickness of the referred instance
+
+    Json::Value instance;
+    if (LookupReferencedInstance(instance, context, contour))
+    {
+      Json::Value info;
+      context.ReadJson(info, instance["ID"].asString());       
+
+      if (info.isMember(SLICE_THICKNESS))
+      {
+        result = boost::lexical_cast<float>(info[SLICE_THICKNESS]["Value"].asString());
+        return true;
+      }
+    }
+
+    return false;
+  }
+                                       
+
+
+  static void GetRtStructuresInfo(RestApi::GetCall& call)
+  {
+    RETRIEVE_CONTEXT(call);
+
+    Json::Value study, series, content;
+    std::string frameOfReference;
+    if (GetRtStructuresInfo(study, series, content, frameOfReference, context, call.GetUriComponent("id", "")))
+    {
+      Json::Value result;
+
+      result["Study"] = study["ID"];
+
+
+      // Lookup the series with the same frame of reference inside this study
+      result["RelatedSeries"] = Json::arrayValue;
+
+      for (Json::Value::ArrayIndex i = 0; i < study["Series"].size(); i++)
+      {
+        Json::Value otherSeries;
+        if (context.GetIndex().LookupResource(otherSeries, study["Series"][i].asString(), ResourceType_Series) &&
+            otherSeries["Instances"].size() > 0)
+        {
+          Json::Value info;
+          context.ReadJson(info, otherSeries["Instances"][0].asString());
+
+          if (info.isMember(FRAME_OF_REFERENCE_UID))
+          {
+            result["RelatedSeries"].append(study["Series"][i].asString());
+          }
+        }
+      }
+
+
+      call.GetOutput().AnswerJson(result);
+    }
+  }
+
+
+  static void GetRtStructuresListOfROIs(RestApi::GetCall& call)
+  {
+    RETRIEVE_CONTEXT(call);
+
+    Json::Value study, series, content;
+    std::string frameOfReference;
+    if (GetRtStructuresInfo(study, series, content, frameOfReference, context, call.GetUriComponent("id", "")))
+    {
+      Json::Value result(Json::arrayValue);
+
+      if (content.isMember(STRUCTURE_SET_ROI_SEQUENCE))
+      {
+        for (Json::Value::ArrayIndex i = 0; i < content[STRUCTURE_SET_ROI_SEQUENCE]["Value"].size(); i++)
+        {
+          if (content[STRUCTURE_SET_ROI_SEQUENCE]["Value"][i].isMember(ROI_NUMBER))
+          {
+            result.append(boost::lexical_cast<int>(content[STRUCTURE_SET_ROI_SEQUENCE]["Value"][i][ROI_NUMBER]["Value"].asString()));
+          }
+        }
+      }
+
+      call.GetOutput().AnswerJson(result);
+    }
+  }
+
+
+  static void GetRtStructuresROI(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       roi.removeMember("InternalIndex");
+       call.GetOutput().AnswerJson(roi);
+     }
+  }
+
+
+  static void GetRtStructuresROIPoints(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       Json::Value result = Json::arrayValue;
+
+       for (Json::Value::ArrayIndex i = 0; i < contour.size(); i++)
+       {
+         if (contour[i][CONTOUR_GEOMETRIC_TYPE]["Value"].asString() == "POINT")
+         {
+           Json::Value p;
+           if (ContourToPoints(p, contour[i][CONTOUR_DATA]["Value"].asString()) &&
+               p.size() == 1)
+           {
+             result.append(p[0]);
+           }
+         }
+       }
+
+       call.GetOutput().AnswerJson(result);
+     }
+  }
+
+
+  static void GetRtStructuresListOfClosedPlanars(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       Json::Value result = Json::arrayValue;
+
+       for (Json::Value::ArrayIndex i = 0; i < contour.size(); i++)
+       {
+         if (contour[i].isMember(CONTOUR_IMAGE_SEQUENCE) &&
+             contour[i].isMember(CONTOUR_GEOMETRIC_TYPE) &&
+             contour[i].isMember(NUMBER_OF_CONTOUR_POINTS) &&
+             contour[i].isMember(CONTOUR_DATA) &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"].size() == 1 &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0].isMember(REFERENCED_SOP_INSTANCE_UID) &&
+             contour[i][CONTOUR_GEOMETRIC_TYPE]["Value"].asString() == "CLOSED_PLANAR")
+         {
+           result.append(i);
+         }
+       }
+
+       call.GetOutput().AnswerJson(result);
+     }
+  }
+
+
+  static void GetRtStructuresSingleClosedPlanar(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour, result;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       unsigned int index = boost::lexical_cast<unsigned int>(call.GetUriComponent("polygon", ""));
+
+       if (GetClosedPlanarPoints(result, context, instanceId, roi, index))
+       {
+         call.GetOutput().AnswerJson(result);
+       }
+     }
+  }
+
+
+  static void GetRtStructuresClosedPlanarThickness(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       unsigned int index = boost::lexical_cast<unsigned int>(call.GetUriComponent("polygon", ""));
+
+       float thickness;
+       if (GetRtStructuresClosedPlanarThickness(thickness, context, contour[index]))
+       {
+         call.GetOutput().AnswerBuffer(boost::lexical_cast<std::string>(thickness), "text/plain");
+       }
+     }
+  }
+
+
+  static bool ComputeClosedPlanarArea(double& area,
+                                      const Json::Value& vertices)
+  {
+    if (vertices.size() <= 1)
+    {
+      area = 0;
+      return true;
+    }
+         
+    // Check that all the points share the same z coordinates
+    for (Json::Value::ArrayIndex i = 1; i < vertices.size(); i++)
+    {
+      static float THRESHOLD = 10.0f * std::numeric_limits<float>::epsilon();
+
+      assert(vertices[i].size() == 3);
+      if (fabs(vertices[i][2].asFloat() - vertices[0][2].asFloat()) > THRESHOLD)
+      {
+        // This point has not the same z coordinate
+        return false;
+      }
+    }
+
+    // Calculate the area of a cartesian polygon
+    // TODO - What happens if self-crossing polygon?
+    typedef boost::geometry::model::d2::point_xy<float> point_type;
+
+    boost::geometry::model::linestring<point_type> points;
+
+    points.resize(vertices.size());
+    for (Json::Value::ArrayIndex i = 0; i < vertices.size(); i++)
+    {
+      float x = vertices[i][0].asFloat();
+      float y = vertices[i][1].asFloat();
+      points[i] = boost::geometry::make<point_type>(x, y);
+    }
+
+    boost::geometry::model::polygon<point_type> poly;
+    boost::geometry::append(poly, points);
+               
+    area = abs(boost::geometry::area(poly));
+    return true;
+  }
+
+
+  static void GetRtStructuresClosedPlanarArea(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour, vertices;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       unsigned int index = boost::lexical_cast<unsigned int>(call.GetUriComponent("polygon", ""));
+
+       double area;
+       if (GetClosedPlanarPoints(vertices, context, instanceId, roi, index) &&
+           ComputeClosedPlanarArea(area, vertices))
+       {
+         call.GetOutput().AnswerBuffer(boost::lexical_cast<std::string>(area), "text/plain");
+       }
+     }
+  }
+
+
+  static void GetRtStructuresInstanceOfClosedPlanar(RestApi::GetCall& call)
+  {
+    RETRIEVE_CONTEXT(call);
+
+    Json::Value roi, contour;
+    std::string instanceId;
+
+    if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                           call.GetUriComponent("id", ""),
+                           call.GetUriComponent("roi", "")))
+    {
+      unsigned int index = boost::lexical_cast<unsigned int>(call.GetUriComponent("polygon", ""));
+
+      Json::Value result;
+      if (LookupReferencedInstance(result, context, contour[index]))
+      {
+        call.GetOutput().AnswerJson(result);
+      }
+    }
+  }
+
+
+  static void GetRtStructuresListOfInstances(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       Json::Value result = Json::arrayValue;
+
+       for (Json::Value::ArrayIndex i = 0; i < contour.size(); i++)
+       {
+         if (contour[i].isMember(CONTOUR_IMAGE_SEQUENCE) &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"].size() == 1 &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0].isMember(REFERENCED_SOP_INSTANCE_UID))
+         {
+           std::string uid = contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0][REFERENCED_SOP_INSTANCE_UID]["Value"].asString();
+
+           std::list<std::string> instance;
+           context.GetIndex().LookupTagValue(instance, DICOM_TAG_SOP_INSTANCE_UID, uid);
+
+           if (instance.size() == 1)
+           {
+             result.append(instance.front());
+           }
+         }
+       }
+
+       call.GetOutput().AnswerJson(result);
+     }
+  }
+
+
+
+  static void GetRtStructuresClosedPlanarsOfInstance(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour, instance;
+     std::string instanceId;
+
+     if (context.GetIndex().LookupResource(instance, call.GetUriComponent("instance", ""), ResourceType_Instance) &&
+         GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       Json::Value result = Json::arrayValue;
+
+       for (Json::Value::ArrayIndex i = 0; i < contour.size(); i++)
+       {
+         if (contour[i].isMember(CONTOUR_DATA) &&
+             contour[i].isMember(CONTOUR_IMAGE_SEQUENCE) &&
+             contour[i].isMember(NUMBER_OF_CONTOUR_POINTS) &&
+             contour[i].isMember(CONTOUR_GEOMETRIC_TYPE) &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"].size() == 1 &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0].isMember(REFERENCED_SOP_INSTANCE_UID) &&
+             contour[i][CONTOUR_GEOMETRIC_TYPE]["Value"].asString() == "CLOSED_PLANAR")
+         {
+           std::string uid = contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0][REFERENCED_SOP_INSTANCE_UID]["Value"].asString();
+
+           Json::Value points;
+           if (uid == instance["MainDicomTags"]["SOPInstanceUID"].asString() &&
+               GetClosedPlanarPoints(points, context, instanceId, roi, i))
+           {
+             result.append(points);
+           }             
+         }
+       }
+
+       call.GetOutput().AnswerJson(result);
+     }
+  }
+
+
+
+  static void GetRtStructuresPointsOfInstance(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour, instance;
+     std::string instanceId;
+
+     if (context.GetIndex().LookupResource(instance, call.GetUriComponent("instance", ""), ResourceType_Instance) &&
+         GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       Json::Value result = Json::arrayValue;
+
+       for (Json::Value::ArrayIndex i = 0; i < contour.size(); i++)
+       {
+         if (contour[i].isMember(CONTOUR_DATA) &&
+             contour[i].isMember(CONTOUR_IMAGE_SEQUENCE) &&
+             contour[i].isMember(CONTOUR_GEOMETRIC_TYPE) &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"].size() == 1 &&
+             contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0].isMember(REFERENCED_SOP_INSTANCE_UID) &&
+             contour[i][CONTOUR_GEOMETRIC_TYPE]["Value"].asString() == "POINT")
+         {
+           std::string uid = contour[i][CONTOUR_IMAGE_SEQUENCE]["Value"][0][REFERENCED_SOP_INSTANCE_UID]["Value"].asString();
+
+           if (uid == instance["MainDicomTags"]["SOPInstanceUID"].asString())
+           {
+             Json::Value p;
+             if (ContourToPoints(p, contour[i][CONTOUR_DATA]["Value"].asString()) &&
+                 p.size() == 1)
+             {
+               result.append(p[0]);
+             }
+           }
+         }
+       }
+
+       call.GetOutput().AnswerJson(result);
+     }
+  }
+
+
+  static void GetRtStructuresVolume(RestApi::GetCall& call)
+  {
+     RETRIEVE_CONTEXT(call);
+
+     Json::Value roi, contour, vertices;
+     std::string instanceId;
+
+     if (GetRtStructuresRoi(roi, contour, instanceId, context, 
+                            call.GetUriComponent("id", ""),
+                            call.GetUriComponent("roi", "")))
+     {
+       double volume = 0;
+
+       for (Json::Value::ArrayIndex i = 0; i < contour.size(); i++)
+       {
+         double area;
+         float thickness;
+
+         if (contour[i].isMember(CONTOUR_GEOMETRIC_TYPE) &&
+             contour[i][CONTOUR_GEOMETRIC_TYPE]["Value"].asString() == "CLOSED_PLANAR" &&
+             GetClosedPlanarPoints(vertices, context, instanceId, roi, i) &&
+             ComputeClosedPlanarArea(area, vertices) &&
+             GetRtStructuresClosedPlanarThickness(thickness, context, contour[i]))
+         {
+           volume += area * static_cast<double>(thickness);
+         }
+       }
+
+       call.GetOutput().AnswerBuffer(boost::lexical_cast<std::string>(volume), "text/plain");
+     }
+  }
+
+
+  RadiotherapyRestApi::RadiotherapyRestApi(ServerContext& context) : OrthancRestApi(context)
+  {
+    Register("/series/{id}/rt-structures", GetRtStructuresInfo);
+    Register("/series/{id}/rt-structures/roi", GetRtStructuresListOfROIs);
+    Register("/series/{id}/rt-structures/roi/{roi}/info", GetRtStructuresROI);
+    Register("/series/{id}/rt-structures/roi/{roi}/points", GetRtStructuresROIPoints);
+    Register("/series/{id}/rt-structures/roi/{roi}/closed-planar", GetRtStructuresListOfClosedPlanars);
+    Register("/series/{id}/rt-structures/roi/{roi}/closed-planar/{polygon}/vertices", GetRtStructuresSingleClosedPlanar);
+    Register("/series/{id}/rt-structures/roi/{roi}/closed-planar/{polygon}/thickness", GetRtStructuresClosedPlanarThickness);
+    Register("/series/{id}/rt-structures/roi/{roi}/closed-planar/{polygon}/instance", GetRtStructuresInstanceOfClosedPlanar);
+    Register("/series/{id}/rt-structures/roi/{roi}/closed-planar/{polygon}/area", GetRtStructuresClosedPlanarArea);
+    Register("/series/{id}/rt-structures/roi/{roi}/instances", GetRtStructuresListOfInstances);
+    Register("/series/{id}/rt-structures/roi/{roi}/instances/{instance}/closed-planar", GetRtStructuresClosedPlanarsOfInstance);
+    Register("/series/{id}/rt-structures/roi/{roi}/instances/{instance}/points", GetRtStructuresPointsOfInstance);
+    Register("/series/{id}/rt-structures/roi/{roi}/volume", GetRtStructuresVolume);
+  }
+
+}
+
+
+//  curl http://localhost:8042/series/0b9e2bb2-605a59aa-f27c0260-9cc4faf6-9d8bf457/rt-structures
+//  curl http://localhost:8042/series/ef041e6b-c855e775-f7e0f7fe-dc3c17dc-533cb8c5/rt-structures

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/OrthancServer/RadiotherapyRestApi.h	Wed Apr 16 16:04:55 2014 +0200
@@ -0,0 +1,44 @@
+/**
+ * Orthanc - A Lightweight, RESTful DICOM Store
+ * Copyright (C) 2012-2013 Medical Physics Department, CHU 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 "OrthancRestApi.h"
+
+namespace Orthanc
+{
+  class RadiotherapyRestApi : public OrthancRestApi
+  {
+  public:
+    RadiotherapyRestApi(ServerContext& context);
+  };
+}

--- a/OrthancServer/ServerContext.h	Wed Apr 16 12:12:55 2014 +0200
+++ b/OrthancServer/ServerContext.h	Wed Apr 16 16:04:55 2014 +0200
@@ -40,6 +40,8 @@
 #include "ServerIndex.h"
 #include "FromDcmtkBridge.h"
 
+#include <boost/thread.hpp>
+
 namespace Orthanc
 {
   /**
@@ -63,6 +65,8 @@
       virtual IDynamicObject* Provide(const std::string& id);
     };
 
+    boost::mutex cacheMutex_;
+
     FileStorage storage_;
     ServerIndex index_;
     CompressedFileStorageAccessor accessor_;
@@ -139,6 +143,13 @@
     // TODO IMPLEMENT MULTITHREADING FOR THIS METHOD
     ParsedDicomFile& GetDicomFile(const std::string& instancePublicId);
 
+    boost::mutex& GetDicomFileMutex()
+    {
+      // TODO IMPROVE MULTITHREADING
+      // Every call to "ParsedDicomFile" must lock this mutex!!!
+      return cacheMutex_;
+    }
+
     LuaContext& GetLuaContext()
     {
       return lua_;

--- a/UnitTestsSources/UnitTestsMain.cpp	Wed Apr 16 12:12:55 2014 +0200
+++ b/UnitTestsSources/UnitTestsMain.cpp	Wed Apr 16 16:04:55 2014 +0200
@@ -554,10 +554,44 @@
   ASSERT_EQ("cd", t[1]);
   ASSERT_EQ("ef", t[2]);
   ASSERT_EQ("", t[3]);
+  
+  Toolbox::TokenizeString(t, "", '|'); 
+  ASSERT_EQ(1, t.size());
+  
+  Toolbox::TokenizeString(t, "aaaaa", '|'); 
+  ASSERT_EQ(1, t.size());
+  ASSERT_EQ("aaaaa", t[0]);
+  
+  Toolbox::TokenizeString(t, "aaa|aa", '|'); 
+  ASSERT_EQ(2, t.size());
+  ASSERT_EQ("aaa", t[0]);
+  ASSERT_EQ("aa", t[1]);
+  
+  Toolbox::TokenizeString(t, "a|aa|ab", '|'); 
+  ASSERT_EQ(3, t.size());
+  ASSERT_EQ("a", t[0]);
+  ASSERT_EQ("aa", t[1]);
+  ASSERT_EQ("ab", t[2]);
+  
+  Toolbox::TokenizeString(t, "||ab", '|'); 
+  ASSERT_EQ(3, t.size());
+  ASSERT_EQ("", t[0]);
+  ASSERT_EQ("", t[1]);
+  ASSERT_EQ("ab", t[2]);
+  
+  Toolbox::TokenizeString(t, "|", '|'); 
+  ASSERT_EQ(2, t.size());
+  ASSERT_EQ("", t[0]);
+  ASSERT_EQ("", t[1]);
+  
+  Toolbox::TokenizeString(t, "||", '|'); 
+  ASSERT_EQ(3, t.size());
+  ASSERT_EQ("", t[0]);
+  ASSERT_EQ("", t[1]);
+  ASSERT_EQ("", t[2]);
 }
 
 
-
 #if defined(__linux)
 #include <endian.h>
 #endif