small adds in OBJ import

include/Algo/Import/importObjTex.h

@@ -369,7 +369,13 @@ public:
 	 */
 	bool createGroupMatVBO_PTN( Utils::VBO* positionVBO, Utils::VBO* texcoordVBO, Utils::VBO* normalVBO);
 
-
+	/**
+	 * @brief add a dart by each face of group in a vector
+	 * @param groupId the group to add
+	 * @param dartFaces the vector in which we want to add
+	 * @return the number of faces added.
+	 */
+	unsigned int storeFacesOfGroup(unsigned int groupId, std::vector<Dart>& dartFaces);
 };
 
 

include/Algo/Import/importObjTex.hpp

@@ -1395,6 +1395,22 @@ bool OBJModel<PFP>::import( const std::string& filename, std::vector<std::string
 
 }
 
+template <typename PFP>
+unsigned int OBJModel<PFP>::storeFacesOfGroup(unsigned int groupId, std::vector<Dart>& dartFaces)
+{
+	unsigned int nb=dartFaces.size();
+
+	TraversorF<typename PFP::MAP> traf(m_map);
+	for (Dart d=traf.begin(); d!= traf.end(); d = traf.next())
+	{
+		if (m_groups[d] == groupId)
+		{
+			dartFaces.push_back(d);
+		}
+	}
+
+	return dartFaces.size()-nb;
+}
 
 
 }