bos #24052 [CEA 24050] Body Fitting with shared faces

+ fix merging polyhedra

src/SMESH/SMESH_MeshEditor.cxx

@@ -6959,9 +6959,19 @@ void SMESH_MeshEditor::MergeNodes (TListOfListOfNodes & theGroupsOfNodes,
 
     for ( size_t i = 0; i < newElemDefs.size(); ++i )
     {
-      if ( i > 0 || !mesh->ChangeElementNodes( elem,
+      bool elemChanged = false;
+      if ( i == 0 )
+      {
+        if ( elem->GetGeomType() == SMDSGeom_POLYHEDRA )
+          elemChanged = mesh->ChangePolyhedronNodes( elem,
+                                                     newElemDefs[i].myNodes,
+                                                     newElemDefs[i].myPolyhedQuantities );
+        else
+          elemChanged = mesh->ChangeElementNodes( elem,
                                                   & newElemDefs[i].myNodes[0],
-                                               newElemDefs[i].myNodes.size() ))
+                                                  newElemDefs[i].myNodes.size() );
+      }
+      if ( i > 0 || !elemChanged )
       {
         if ( i == 0 )
         {
@@ -7128,6 +7138,7 @@ bool SMESH_MeshEditor::applyMerge( const SMDS_MeshElement* elem,
         // each face has to be analyzed in order to check volume validity
         if ( const SMDS_MeshVolume* aPolyedre = SMDS_Mesh::DownCast< SMDS_MeshVolume >( elem ))
         {
+          toRemove = false;
           int nbFaces = aPolyedre->NbFaces();
 
           vector<const SMDS_MeshNode *>& poly_nodes = newElemDefs[0].myNodes;

src/SMESHDS/SMESHDS_Mesh.cxx

@@ -256,14 +256,14 @@ bool SMESHDS_Mesh
 {
   ASSERT(nodes.size() > 3);
 
+  size_t i, len = nodes.size();
+  std::vector<smIdType> nodes_ids( len );
+  for ( i = 0; i < len; i++ )
+    nodes_ids[i] = nodes[i]->GetID();
+
   if ( !SMDS_Mesh::ChangePolyhedronNodes( elem, nodes, quantities ))
     return false;
 
-  smIdType i, len = nodes.size();
-  std::vector<smIdType> nodes_ids (len);
-  for (i = 0; i < len; i++) {
-    nodes_ids[i] = nodes[i]->GetID();
-  }
   myScript->ChangePolyhedronNodes(elem->GetID(), nodes_ids, quantities);
 
   return true;