diff --git a/hurricane/doc/hurricane/Pad.dox b/hurricane/doc/hurricane/Pad.dox
index da4f0cc8..6d98becb 100644
--- a/hurricane/doc/hurricane/Pad.dox
+++ b/hurricane/doc/hurricane/Pad.dox
@@ -23,7 +23,7 @@
   */
  //  \{
 
- /*! \function     Pad* Pad::create(Net* net, Layer* layer, const Box& boundingBox);
+ /*! \function     Pad* Pad::create(Net* net, const Layer* layer, const Box& boundingBox);
   *                No description.
   */
 
diff --git a/hurricane/src/CMakeLists.txt b/hurricane/src/CMakeLists.txt
index b25d9854..756fd73c 100644
--- a/hurricane/src/CMakeLists.txt
+++ b/hurricane/src/CMakeLists.txt
@@ -1,4 +1,4 @@
 add_subdirectory(hurricane)
 add_subdirectory(hinspector)
 add_subdirectory(hviewer)
-add_subdirectory(pyext)
+add_subdirectory(isobar)
diff --git a/hurricane/src/pyext/CMakeLists.txt b/hurricane/src/isobar/CMakeLists.txt
similarity index 98%
rename from hurricane/src/pyext/CMakeLists.txt
rename to hurricane/src/isobar/CMakeLists.txt
index 6ab6256f..b2186d33 100644
--- a/hurricane/src/pyext/CMakeLists.txt
+++ b/hurricane/src/isobar/CMakeLists.txt
@@ -1,7 +1,7 @@
 
    include_directories ( ${PYTHON_INCLUDE_PATH}
                          ${HURRICANE_SOURCE_DIR}/src/hurricane
-                         ${HURRICANE_SOURCE_DIR}/src/pyext
+                         ${HURRICANE_SOURCE_DIR}/src/isobar
                        )
                    set ( sources  ProxyProperty.cpp
                                   PyBox.cpp
diff --git a/hurricane/src/pyext/CMakeLists.txt.backup b/hurricane/src/isobar/CMakeLists.txt.backup
similarity index 100%
rename from hurricane/src/pyext/CMakeLists.txt.backup
rename to hurricane/src/isobar/CMakeLists.txt.backup
diff --git a/hurricane/src/pyext/Makefile.am b/hurricane/src/isobar/Makefile.am
similarity index 100%
rename from hurricane/src/pyext/Makefile.am
rename to hurricane/src/isobar/Makefile.am
diff --git a/hurricane/src/pyext/ProxyProperty.cpp b/hurricane/src/isobar/ProxyProperty.cpp
similarity index 100%
rename from hurricane/src/pyext/ProxyProperty.cpp
rename to hurricane/src/isobar/ProxyProperty.cpp
diff --git a/hurricane/src/pyext/PyBox.cpp b/hurricane/src/isobar/PyBox.cpp
similarity index 100%
rename from hurricane/src/pyext/PyBox.cpp
rename to hurricane/src/isobar/PyBox.cpp
diff --git a/hurricane/src/pyext/PyCell.cpp b/hurricane/src/isobar/PyCell.cpp
similarity index 100%
rename from hurricane/src/pyext/PyCell.cpp
rename to hurricane/src/isobar/PyCell.cpp
diff --git a/hurricane/src/pyext/PyCellLocator.cpp b/hurricane/src/isobar/PyCellLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyCellLocator.cpp
rename to hurricane/src/isobar/PyCellLocator.cpp
diff --git a/hurricane/src/pyext/PyComponent.cpp b/hurricane/src/isobar/PyComponent.cpp
similarity index 100%
rename from hurricane/src/pyext/PyComponent.cpp
rename to hurricane/src/isobar/PyComponent.cpp
diff --git a/hurricane/src/pyext/PyComponentLocator.cpp b/hurricane/src/isobar/PyComponentLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyComponentLocator.cpp
rename to hurricane/src/isobar/PyComponentLocator.cpp
diff --git a/hurricane/src/pyext/PyContact.cpp b/hurricane/src/isobar/PyContact.cpp
similarity index 100%
rename from hurricane/src/pyext/PyContact.cpp
rename to hurricane/src/isobar/PyContact.cpp
diff --git a/hurricane/src/pyext/PyDataBase.cpp b/hurricane/src/isobar/PyDataBase.cpp
similarity index 100%
rename from hurricane/src/pyext/PyDataBase.cpp
rename to hurricane/src/isobar/PyDataBase.cpp
diff --git a/hurricane/src/pyext/PyDbU.cpp b/hurricane/src/isobar/PyDbU.cpp
similarity index 100%
rename from hurricane/src/pyext/PyDbU.cpp
rename to hurricane/src/isobar/PyDbU.cpp
diff --git a/hurricane/src/pyext/PyEntity.cpp b/hurricane/src/isobar/PyEntity.cpp
similarity index 100%
rename from hurricane/src/pyext/PyEntity.cpp
rename to hurricane/src/isobar/PyEntity.cpp
diff --git a/hurricane/src/pyext/PyHorizontal.cpp b/hurricane/src/isobar/PyHorizontal.cpp
similarity index 100%
rename from hurricane/src/pyext/PyHorizontal.cpp
rename to hurricane/src/isobar/PyHorizontal.cpp
diff --git a/hurricane/src/pyext/PyHurricane.cpp b/hurricane/src/isobar/PyHurricane.cpp
similarity index 100%
rename from hurricane/src/pyext/PyHurricane.cpp
rename to hurricane/src/isobar/PyHurricane.cpp
diff --git a/hurricane/src/pyext/PyHyperNet.cpp b/hurricane/src/isobar/PyHyperNet.cpp
similarity index 100%
rename from hurricane/src/pyext/PyHyperNet.cpp
rename to hurricane/src/isobar/PyHyperNet.cpp
diff --git a/hurricane/src/pyext/PyInstance.cpp b/hurricane/src/isobar/PyInstance.cpp
similarity index 100%
rename from hurricane/src/pyext/PyInstance.cpp
rename to hurricane/src/isobar/PyInstance.cpp
diff --git a/hurricane/src/pyext/PyInstanceLocator.cpp b/hurricane/src/isobar/PyInstanceLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyInstanceLocator.cpp
rename to hurricane/src/isobar/PyInstanceLocator.cpp
diff --git a/hurricane/src/pyext/PyLayer.cpp b/hurricane/src/isobar/PyLayer.cpp
similarity index 100%
rename from hurricane/src/pyext/PyLayer.cpp
rename to hurricane/src/isobar/PyLayer.cpp
diff --git a/hurricane/src/pyext/PyLibrary.cpp b/hurricane/src/isobar/PyLibrary.cpp
similarity index 100%
rename from hurricane/src/pyext/PyLibrary.cpp
rename to hurricane/src/isobar/PyLibrary.cpp
diff --git a/hurricane/src/pyext/PyName.cpp b/hurricane/src/isobar/PyName.cpp
similarity index 100%
rename from hurricane/src/pyext/PyName.cpp
rename to hurricane/src/isobar/PyName.cpp
diff --git a/hurricane/src/pyext/PyNet.cpp b/hurricane/src/isobar/PyNet.cpp
similarity index 100%
rename from hurricane/src/pyext/PyNet.cpp
rename to hurricane/src/isobar/PyNet.cpp
diff --git a/hurricane/src/pyext/PyNetLocator.cpp b/hurricane/src/isobar/PyNetLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyNetLocator.cpp
rename to hurricane/src/isobar/PyNetLocator.cpp
diff --git a/hurricane/src/pyext/PyOccurrence.cpp b/hurricane/src/isobar/PyOccurrence.cpp
similarity index 100%
rename from hurricane/src/pyext/PyOccurrence.cpp
rename to hurricane/src/isobar/PyOccurrence.cpp
diff --git a/hurricane/src/pyext/PyOccurrenceLocator.cpp b/hurricane/src/isobar/PyOccurrenceLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyOccurrenceLocator.cpp
rename to hurricane/src/isobar/PyOccurrenceLocator.cpp
diff --git a/hurricane/src/pyext/PyPath.cpp b/hurricane/src/isobar/PyPath.cpp
similarity index 100%
rename from hurricane/src/pyext/PyPath.cpp
rename to hurricane/src/isobar/PyPath.cpp
diff --git a/hurricane/src/pyext/PyPin.cpp b/hurricane/src/isobar/PyPin.cpp
similarity index 100%
rename from hurricane/src/pyext/PyPin.cpp
rename to hurricane/src/isobar/PyPin.cpp
diff --git a/hurricane/src/pyext/PyPinLocator.cpp b/hurricane/src/isobar/PyPinLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyPinLocator.cpp
rename to hurricane/src/isobar/PyPinLocator.cpp
diff --git a/hurricane/src/pyext/PyPlug.cpp b/hurricane/src/isobar/PyPlug.cpp
similarity index 100%
rename from hurricane/src/pyext/PyPlug.cpp
rename to hurricane/src/isobar/PyPlug.cpp
diff --git a/hurricane/src/pyext/PyPlugLocator.cpp b/hurricane/src/isobar/PyPlugLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyPlugLocator.cpp
rename to hurricane/src/isobar/PyPlugLocator.cpp
diff --git a/hurricane/src/pyext/PyPoint.cpp b/hurricane/src/isobar/PyPoint.cpp
similarity index 100%
rename from hurricane/src/pyext/PyPoint.cpp
rename to hurricane/src/isobar/PyPoint.cpp
diff --git a/hurricane/src/pyext/PyReference.cpp b/hurricane/src/isobar/PyReference.cpp
similarity index 100%
rename from hurricane/src/pyext/PyReference.cpp
rename to hurricane/src/isobar/PyReference.cpp
diff --git a/hurricane/src/pyext/PyReferenceLocator.cpp b/hurricane/src/isobar/PyReferenceLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PyReferenceLocator.cpp
rename to hurricane/src/isobar/PyReferenceLocator.cpp
diff --git a/hurricane/src/pyext/PySegment.cpp b/hurricane/src/isobar/PySegment.cpp
similarity index 100%
rename from hurricane/src/pyext/PySegment.cpp
rename to hurricane/src/isobar/PySegment.cpp
diff --git a/hurricane/src/pyext/PySegmentLocator.cpp b/hurricane/src/isobar/PySegmentLocator.cpp
similarity index 100%
rename from hurricane/src/pyext/PySegmentLocator.cpp
rename to hurricane/src/isobar/PySegmentLocator.cpp
diff --git a/hurricane/src/pyext/PyTechnology.cpp b/hurricane/src/isobar/PyTechnology.cpp
similarity index 100%
rename from hurricane/src/pyext/PyTechnology.cpp
rename to hurricane/src/isobar/PyTechnology.cpp
diff --git a/hurricane/src/pyext/PyTransformation.cpp b/hurricane/src/isobar/PyTransformation.cpp
similarity index 100%
rename from hurricane/src/pyext/PyTransformation.cpp
rename to hurricane/src/isobar/PyTransformation.cpp
diff --git a/hurricane/src/pyext/PyUpdateSession.cpp b/hurricane/src/isobar/PyUpdateSession.cpp
similarity index 100%
rename from hurricane/src/pyext/PyUpdateSession.cpp
rename to hurricane/src/isobar/PyUpdateSession.cpp
diff --git a/hurricane/src/pyext/PyVertical.cpp b/hurricane/src/isobar/PyVertical.cpp
similarity index 100%
rename from hurricane/src/pyext/PyVertical.cpp
rename to hurricane/src/isobar/PyVertical.cpp
diff --git a/hurricane/src/pyext/hurricane/isobar/ProxyProperty.h b/hurricane/src/isobar/hurricane/isobar/ProxyProperty.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/ProxyProperty.h
rename to hurricane/src/isobar/hurricane/isobar/ProxyProperty.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyBox.h b/hurricane/src/isobar/hurricane/isobar/PyBox.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyBox.h
rename to hurricane/src/isobar/hurricane/isobar/PyBox.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyCell.h b/hurricane/src/isobar/hurricane/isobar/PyCell.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyCell.h
rename to hurricane/src/isobar/hurricane/isobar/PyCell.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyCellLocator.h b/hurricane/src/isobar/hurricane/isobar/PyCellLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyCellLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyCellLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyComponent.h b/hurricane/src/isobar/hurricane/isobar/PyComponent.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyComponent.h
rename to hurricane/src/isobar/hurricane/isobar/PyComponent.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyComponentLocator.h b/hurricane/src/isobar/hurricane/isobar/PyComponentLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyComponentLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyComponentLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyContact.h b/hurricane/src/isobar/hurricane/isobar/PyContact.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyContact.h
rename to hurricane/src/isobar/hurricane/isobar/PyContact.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyDataBase.h b/hurricane/src/isobar/hurricane/isobar/PyDataBase.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyDataBase.h
rename to hurricane/src/isobar/hurricane/isobar/PyDataBase.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyDbU.h b/hurricane/src/isobar/hurricane/isobar/PyDbU.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyDbU.h
rename to hurricane/src/isobar/hurricane/isobar/PyDbU.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyEntity.h b/hurricane/src/isobar/hurricane/isobar/PyEntity.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyEntity.h
rename to hurricane/src/isobar/hurricane/isobar/PyEntity.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyHorizontal.h b/hurricane/src/isobar/hurricane/isobar/PyHorizontal.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyHorizontal.h
rename to hurricane/src/isobar/hurricane/isobar/PyHorizontal.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyHurricane.h b/hurricane/src/isobar/hurricane/isobar/PyHurricane.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyHurricane.h
rename to hurricane/src/isobar/hurricane/isobar/PyHurricane.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyHyperNet.h b/hurricane/src/isobar/hurricane/isobar/PyHyperNet.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyHyperNet.h
rename to hurricane/src/isobar/hurricane/isobar/PyHyperNet.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyInstance.h b/hurricane/src/isobar/hurricane/isobar/PyInstance.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyInstance.h
rename to hurricane/src/isobar/hurricane/isobar/PyInstance.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyInstanceLocator.h b/hurricane/src/isobar/hurricane/isobar/PyInstanceLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyInstanceLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyInstanceLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyLayer.h b/hurricane/src/isobar/hurricane/isobar/PyLayer.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyLayer.h
rename to hurricane/src/isobar/hurricane/isobar/PyLayer.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyLibrary.h b/hurricane/src/isobar/hurricane/isobar/PyLibrary.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyLibrary.h
rename to hurricane/src/isobar/hurricane/isobar/PyLibrary.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyName.h b/hurricane/src/isobar/hurricane/isobar/PyName.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyName.h
rename to hurricane/src/isobar/hurricane/isobar/PyName.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyNet.h b/hurricane/src/isobar/hurricane/isobar/PyNet.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyNet.h
rename to hurricane/src/isobar/hurricane/isobar/PyNet.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyNetLocator.h b/hurricane/src/isobar/hurricane/isobar/PyNetLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyNetLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyNetLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyOccurrence.h b/hurricane/src/isobar/hurricane/isobar/PyOccurrence.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyOccurrence.h
rename to hurricane/src/isobar/hurricane/isobar/PyOccurrence.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyOccurrenceLocator.h b/hurricane/src/isobar/hurricane/isobar/PyOccurrenceLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyOccurrenceLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyOccurrenceLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyPath.h b/hurricane/src/isobar/hurricane/isobar/PyPath.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyPath.h
rename to hurricane/src/isobar/hurricane/isobar/PyPath.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyPin.h b/hurricane/src/isobar/hurricane/isobar/PyPin.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyPin.h
rename to hurricane/src/isobar/hurricane/isobar/PyPin.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyPinLocator.h b/hurricane/src/isobar/hurricane/isobar/PyPinLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyPinLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyPinLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyPlug.h b/hurricane/src/isobar/hurricane/isobar/PyPlug.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyPlug.h
rename to hurricane/src/isobar/hurricane/isobar/PyPlug.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyPlugLocator.h b/hurricane/src/isobar/hurricane/isobar/PyPlugLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyPlugLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyPlugLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyPoint.h b/hurricane/src/isobar/hurricane/isobar/PyPoint.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyPoint.h
rename to hurricane/src/isobar/hurricane/isobar/PyPoint.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyReference.h b/hurricane/src/isobar/hurricane/isobar/PyReference.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyReference.h
rename to hurricane/src/isobar/hurricane/isobar/PyReference.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyReferenceLocator.h b/hurricane/src/isobar/hurricane/isobar/PyReferenceLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyReferenceLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PyReferenceLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PySegment.h b/hurricane/src/isobar/hurricane/isobar/PySegment.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PySegment.h
rename to hurricane/src/isobar/hurricane/isobar/PySegment.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PySegmentLocator.h b/hurricane/src/isobar/hurricane/isobar/PySegmentLocator.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PySegmentLocator.h
rename to hurricane/src/isobar/hurricane/isobar/PySegmentLocator.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyTechnology.h b/hurricane/src/isobar/hurricane/isobar/PyTechnology.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyTechnology.h
rename to hurricane/src/isobar/hurricane/isobar/PyTechnology.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyTransformation.h b/hurricane/src/isobar/hurricane/isobar/PyTransformation.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyTransformation.h
rename to hurricane/src/isobar/hurricane/isobar/PyTransformation.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyUpdateSession.h b/hurricane/src/isobar/hurricane/isobar/PyUpdateSession.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyUpdateSession.h
rename to hurricane/src/isobar/hurricane/isobar/PyUpdateSession.h
diff --git a/hurricane/src/pyext/hurricane/isobar/PyVertical.h b/hurricane/src/isobar/hurricane/isobar/PyVertical.h
similarity index 100%
rename from hurricane/src/pyext/hurricane/isobar/PyVertical.h
rename to hurricane/src/isobar/hurricane/isobar/PyVertical.h