0021275: EDF 1681 SMESH: Find the number of nodes of any group

+    long GetNumberOfNodes();
+    long_array GetNodeIDs();
+    boolean IsNodeInfoAvailable();

idl/SMESH_Group.idl

@@ -83,6 +83,23 @@ module SMESH
      */
     long_array GetListOfID();
 
+    /*!
+     * Get the number of nodes of cells included to the group
+     * For a nodal group returns the same value as Size() function
+     */
+    long GetNumberOfNodes();
+
+    /*!
+     * Get IDs of nodes of cells included to the group
+     * For a nodal group returns result of GetListOfID() function
+     */
+    long_array GetNodeIDs();
+
+    /*!
+     * Return true if GetNumberOfNodes() won't take a long time for computation
+     */
+    boolean IsNodeInfoAvailable();
+
     /*!
      * Sets group color
      */
@@ -107,7 +124,7 @@ module SMESH
   }; 
 
   /*!
-   * SMESH_Group: interface of group object
+   * SMESH_Group: interface of a standalone group object
    */
   interface SMESH_Group : SMESH_GroupBase
   {
@@ -141,7 +158,7 @@ module SMESH
   };
 
   /*!
-   * SMESH_GroupOnGeom: interface of group object linked to geometry
+   * SMESH_GroupOnGeom: interface of a group object linked to geometry
    */
   interface SMESH_GroupOnGeom : SMESH_GroupBase
   {
@@ -149,7 +166,7 @@ module SMESH
   };
 
   /*!
-   * SMESH_GroupOnFilter: interface of group object defined by filter
+   * SMESH_GroupOnFilter: interface of a group object defined by filter
    */
   interface SMESH_GroupOnFilter : SMESH_GroupBase
   {

src/SMESH_I/SMESH_Group_i.cxx

@@ -55,7 +55,9 @@ SMESH_GroupBase_i::SMESH_GroupBase_i( PortableServer::POA_ptr thePOA,
                                       const int               theLocalID )
 : SALOME::GenericObj_i( thePOA ),
   myMeshServant( theMeshServant ), 
-  myLocalID( theLocalID )
+  myLocalID( theLocalID ),
+  myNbNodes(-1),
+  myGroupDSTic(0)
 {
   // PAL7962: san -- To ensure correct mapping of servant and correct reference counting in GenericObj_i,
   // servant activation is performed by SMESH_Mesh_i::createGroup()
@@ -436,6 +438,88 @@ SMESH::long_array* SMESH_GroupBase_i::GetListOfID()
   return aRes._retn();
 }
 
+namespace
+{
+  //================================================================================
+  /*!
+   * \brief return nodes of elements pointered by iterator
+   */
+  //================================================================================
+
+  void getNodesOfElements(SMDS_ElemIteratorPtr        elemIt,
+                          set<const SMDS_MeshNode* >& nodes)
+  {
+    while ( elemIt->more() )
+    {
+      const SMDS_MeshElement* e = elemIt->next();
+      nodes.insert( e->begin_nodes(), e->end_nodes() );
+    }
+  }
+}
+  
+//================================================================================
+/*!
+ * \brief return the number of nodes of cells included to the group
+ */
+//================================================================================
+
+CORBA::Long SMESH_GroupBase_i::GetNumberOfNodes()
+{
+  if ( GetType() == SMESH::NODE )
+    return Size();
+
+  if ( SMESHDS_GroupBase* g = GetGroupDS())
+  {
+    if ( myNbNodes < 0 || g->GetTic() != myGroupDSTic )
+    {      
+      set<const SMDS_MeshNode* > nodes;
+      getNodesOfElements( g->GetElements(), nodes );
+      myNbNodes = nodes.size();
+      myGroupDSTic = g->GetTic();
+    }
+  }
+  return myNbNodes;
+}
+
+//================================================================================
+/*!
+ * \brief Return true if GetNumberOfNodes() won't take a long time for computation
+ */
+//================================================================================
+
+CORBA::Boolean SMESH_GroupBase_i::IsNodeInfoAvailable()
+{
+  if ( GetType() == SMESH::NODE || Size() < 100000 )
+    return true;
+  if ( SMESHDS_GroupBase* g = GetGroupDS())
+    return ( myNbNodes > -1 && g->GetTic() == myGroupDSTic);
+  return false;
+}
+
+//================================================================================
+/*!
+ * \brief Return IDs of nodes of cells included to the group
+ */
+//================================================================================
+
+SMESH::long_array* SMESH_GroupBase_i::GetNodeIDs()
+{
+  if ( GetType() == SMESH::NODE )
+    return GetListOfID();
+
+  SMESH::long_array_var aRes = new SMESH::long_array();
+  if ( SMESHDS_GroupBase* g = GetGroupDS())
+  {
+    set<const SMDS_MeshNode* > nodes;
+    getNodesOfElements( g->GetElements(), nodes );
+    aRes->length( nodes.size() );
+    set<const SMDS_MeshNode*>::iterator nIt = nodes.begin(), nEnd = nodes.end();
+    for ( int i = 0; nIt != nEnd; ++nIt, ++i )
+      aRes[i] = (*nIt)->GetID();
+  }
+  return aRes._retn();
+}
+
 //=============================================================================
 /*!
  *  

src/SMESH_I/SMESH_Group_i.hxx

@@ -64,6 +64,9 @@ class SMESH_I_EXPORT SMESH_GroupBase_i:
   CORBA::Boolean Contains(CORBA::Long elem_id);
   CORBA::Long GetID(CORBA::Long elem_index);
   SMESH::long_array* GetListOfID();
+  SMESH::long_array* GetNodeIDs();
+  CORBA::Long GetNumberOfNodes();
+  CORBA::Boolean IsNodeInfoAvailable(); // for gui
   SMESH::SMESH_Mesh_ptr GetMesh();
 
   /*!
@@ -100,6 +103,8 @@ private:
 
   void changeLocalId(int localId) { myLocalID = localId; }
   friend class SMESH_Mesh_i;
+
+  int myNbNodes, myGroupDSTic;
 };
 
 // ======