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PAL13330( When mesh generation does not success, trace where )
[modules/smesh.git] / src / SMESH / SMESH_subMesh.cxx
index 750c6c3a0ab06054bd1f76c46737dedc327feae7..f8dbe11d48e8a012061b5aaa8543fce99c998d6a 100644 (file)
 //  Module : SMESH
 //  $Header$
 
-using namespace std;
 #include "SMESH_subMesh.hxx"
 
-#include "SMESH_subMeshEventListener.hxx"
-#include "SMESH_Gen.hxx"
-#include "SMESH_Mesh.hxx"
-#include "SMESH_Hypothesis.hxx"
 #include "SMESH_Algo.hxx"
+#include "SMESH_Gen.hxx"
 #include "SMESH_HypoFilter.hxx"
+#include "SMESH_Hypothesis.hxx"
+#include "SMESH_Mesh.hxx"
+#include "SMESH_MesherHelper.hxx"
+#include "SMESH_subMeshEventListener.hxx"
+#include "SMESH_Comment.hxx"
+#include "SMDS_SetIterator.hxx"
 
 #include "utilities.h"
 #include "OpUtil.hxx"
 
 #include <BRep_Builder.hxx>
-
+#include <BRep_Tool.hxx>
 #include <TopExp.hxx>
-#include <TopoDS_Compound.hxx>
-#include <TopTools_MapOfShape.hxx>
-#include <TopTools_ListOfShape.hxx>
-#include <TopTools_ListIteratorOfListOfShape.hxx>
 #include <TopTools_IndexedDataMapOfShapeListOfShape.hxx>
-
-#ifdef _DEBUG_
-#include <gp_Pnt.hxx>
-#include <BRep_Tool.hxx>
-#include <TopoDS.hxx>
 #include <TopTools_IndexedMapOfShape.hxx>
-#endif
+#include <TopTools_ListIteratorOfListOfShape.hxx>
+#include <TopTools_ListOfShape.hxx>
+#include <TopTools_MapOfShape.hxx>
+#include <TopoDS.hxx>
+#include <TopoDS_Compound.hxx>
+#include <gp_Pnt.hxx>
 
 #include <Standard_Failure.hxx>
 #include <Standard_ErrorHandler.hxx>
 
+using namespace std;
+
 //=============================================================================
 /*!
  *  default constructor:
  */
 //=============================================================================
 
-SMESH_subMesh::SMESH_subMesh(int Id, SMESH_Mesh * father, SMESHDS_Mesh * meshDS,
-       const TopoDS_Shape & aSubShape)
+SMESH_subMesh::SMESH_subMesh(int                  Id,
+                             SMESH_Mesh *         father,
+                             SMESHDS_Mesh *       meshDS,
+                             const TopoDS_Shape & aSubShape)
 {
        _subShape = aSubShape;
-       _meshDS = meshDS;
        _subMeshDS = meshDS->MeshElements(_subShape);   // may be null ...
        _father = father;
        _Id = Id;
-       _dependenceAnalysed = false;
+       _dependenceAnalysed = _alwaysComputed = false;
 
        if (_subShape.ShapeType() == TopAbs_VERTEX)
        {
@@ -96,6 +97,7 @@ SMESH_subMesh::~SMESH_subMesh()
 {
   MESSAGE("SMESH_subMesh::~SMESH_subMesh");
   // ****
+  DeleteOwnListeners();
 }
 
 //=============================================================================
@@ -118,16 +120,8 @@ int SMESH_subMesh::GetId() const
 
 SMESHDS_SubMesh * SMESH_subMesh::GetSubMeshDS()
 {
-  // submesh appears in DS only when a mesher set nodes and elements on it
-  if (_subMeshDS==NULL)
-  {
-    _subMeshDS = _meshDS->MeshElements(_subShape);     // may be null ...
-//     if (_subMeshDS==NULL)
-//     {
-//       MESSAGE("problem... subMesh still empty");
-//     }
-  }
-  return _subMeshDS;
+  // submesh appears in DS only when a mesher set nodes and elements on a shape
+  return _subMeshDS ? _subMeshDS : _subMeshDS = _father->GetMeshDS()->MeshElements(_subShape); // may be null
 }
 
 //=============================================================================
@@ -138,9 +132,10 @@ SMESHDS_SubMesh * SMESH_subMesh::GetSubMeshDS()
 
 SMESHDS_SubMesh* SMESH_subMesh::CreateSubMeshDS()
 {
-  if ( !GetSubMeshDS() )
-    _meshDS->NewSubMesh( _meshDS->ShapeToIndex( _subShape ) );
-
+  if ( !GetSubMeshDS() ) {
+    SMESHDS_Mesh* meshDS = _father->GetMeshDS();
+    meshDS->NewSubMesh( meshDS->ShapeToIndex( _subShape ) );
+  }
   return GetSubMeshDS();
 }
 
@@ -152,29 +147,65 @@ SMESHDS_SubMesh* SMESH_subMesh::CreateSubMeshDS()
 
 SMESH_subMesh *SMESH_subMesh::GetFirstToCompute()
 {
-  const map < int, SMESH_subMesh * >&subMeshes = DependsOn();
-  SMESH_subMesh *firstToCompute = 0;
+  SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(true,false);
+  while ( smIt->more() ) {
+    SMESH_subMesh *sm = smIt->next();
+    if ( sm->GetComputeState() == READY_TO_COMPUTE )
+      return sm;
+  }
+  return 0;                     // nothing to compute
+}
 
-  map < int, SMESH_subMesh * >::const_iterator itsub;
-  for (itsub = subMeshes.begin(); itsub != subMeshes.end(); itsub++)
-  {
-    SMESH_subMesh *sm = (*itsub).second;
-    bool readyToCompute = (sm->GetComputeState() == READY_TO_COMPUTE);
-    if (readyToCompute)
+//================================================================================
+/*!
+ * \brief Allow algo->Compute() if a subshape of lower dim is meshed but
+ *        none mesh entity is bound to it (PAL13615, 2nd part)
+ */
+//================================================================================
+
+void SMESH_subMesh::SetIsAlwaysComputed(bool isAlCo)
+{
+  _alwaysComputed = isAlCo;
+  if ( _alwaysComputed )
+    _computeState = COMPUTE_OK;
+  else
+    ComputeStateEngine( CHECK_COMPUTE_STATE );
+}
+
+//=======================================================================
+//function : IsMeshComputed
+//purpose  : check if _subMeshDS contains mesh elements
+//=======================================================================
+
+bool SMESH_subMesh::IsMeshComputed() const
+{
+  if ( _alwaysComputed )
+    return true;
+  // algo may bind a submesh not to _subShape, eg 3D algo
+  // sets nodes on SHELL while _subShape may be SOLID
+
+  SMESHDS_Mesh* meshDS = _father->GetMeshDS();
+  int dim = SMESH_Gen::GetShapeDim( _subShape );
+  int type = _subShape.ShapeType();
+  for ( ; type <= TopAbs_VERTEX; type++) {
+    if ( dim == SMESH_Gen::GetShapeDim( (TopAbs_ShapeEnum) type ))
     {
-      firstToCompute = sm;
-      break;
+      TopExp_Explorer exp( _subShape, (TopAbs_ShapeEnum) type );
+      for ( ; exp.More(); exp.Next() )
+      {
+        if ( SMESHDS_SubMesh * smDS = meshDS->MeshElements( exp.Current() ))
+        {
+          bool computed = (dim > 0) ? smDS->NbElements() : smDS->NbNodes();
+          if ( computed )
+            return true;
+        }
+      }
     }
+    else
+      break;
   }
-  if (firstToCompute)
-  {
-    return firstToCompute;     // a subMesh of this
-  }
-  if (_computeState == READY_TO_COMPUTE)
-  {
-    return this;               // this
-  }
-  return 0;                     // nothing to compute
+
+  return false;
 }
 
 //=============================================================================
@@ -185,31 +216,26 @@ SMESH_subMesh *SMESH_subMesh::GetFirstToCompute()
 
 bool SMESH_subMesh::SubMeshesComputed()
 {
-  //MESSAGE("SMESH_subMesh::SubMeshesComputed");
-  const map < int, SMESH_subMesh * >&subMeshes = DependsOn();
-
   int myDim = SMESH_Gen::GetShapeDim( _subShape );
   int dimToCheck = myDim - 1;
   bool subMeshesComputed = true;
-  map < int, SMESH_subMesh * >::const_iterator itsub;
-  for (itsub = subMeshes.begin(); itsub != subMeshes.end(); itsub++)
+  // check subMeshes with upper dimension => reverse iteration
+  SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,true);
+  while ( smIt->more() )
   {
-    SMESH_subMesh *sm = (*itsub).second;
+    SMESH_subMesh *sm = smIt->next();
+    if ( sm->_alwaysComputed )
+      continue;
     const TopoDS_Shape & ss = sm->GetSubShape();
     // MSV 07.04.2006: restrict checking to myDim-1 only. Ex., there is no sense
     // in checking of existence of edges if the algo needs only faces. Moreover,
     // degenerated edges may have no submesh, as after computing NETGEN_2D.
     int dim = SMESH_Gen::GetShapeDim( ss );
     if (dim < dimToCheck)
-      continue;
+      break; // the rest subMeshes are all of less dimension
     SMESHDS_SubMesh * ds = sm->GetSubMeshDS();
-    // PAL10974.
-    // There are some tricks with compute states, e.g. Penta_3D leaves
-    // one face with READY_TO_COMPUTE state in order to be able to
-    // recompute 3D when a locale triangle hypo changes (see PAL7428).
-    // So we check if mesh is really present
     bool computeOk = (sm->GetComputeState() == COMPUTE_OK ||
-                      (ds && ( ds->GetNodes()->more() || ds->GetElements()->more() )));
+                      (ds && ( ds->NbNodes() || ds->NbElements() )));
     if (!computeOk)
     {
       int type = ss.ShapeType();
@@ -274,16 +300,12 @@ bool SMESH_subMesh::SubMeshesComputed()
 
 bool SMESH_subMesh::SubMeshesReady()
 {
-  MESSAGE("SMESH_subMesh::SubMeshesReady");
-  const map < int, SMESH_subMesh * >&subMeshes = DependsOn();
-
   bool subMeshesReady = true;
-  map < int, SMESH_subMesh * >::const_iterator itsub;
-  for (itsub = subMeshes.begin(); itsub != subMeshes.end(); itsub++)
-  {
-    SMESH_subMesh *sm = (*itsub).second;
-    bool computeOk = ((sm->GetComputeState() == COMPUTE_OK)
-                      || (sm->GetComputeState() == READY_TO_COMPUTE));
+  SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,true);
+  while ( smIt->more() ) {
+    SMESH_subMesh *sm = smIt->next();
+    bool computeOk = (sm->GetComputeState() == COMPUTE_OK ||
+                      sm->GetComputeState() == READY_TO_COMPUTE);
     if (!computeOk)
     {
       subMeshesReady = false;
@@ -306,7 +328,7 @@ bool SMESH_subMesh::SubMeshesReady()
  */
 //=============================================================================
 
-const map < int, SMESH_subMesh * >&SMESH_subMesh::DependsOn()
+const map < int, SMESH_subMesh * >& SMESH_subMesh::DependsOn()
 {
   if (_dependenceAnalysed)
     return _mapDepend;
@@ -482,6 +504,7 @@ bool SMESH_subMesh::IsApplicableHypotesis(const SMESH_Hypothesis* theHypothesis,
 
   // hypothesis
   switch ( theShapeType ) {
+  case TopAbs_VERTEX:
   case TopAbs_EDGE:
   case TopAbs_FACE:
   case TopAbs_SOLID:
@@ -523,31 +546,47 @@ SMESH_Hypothesis::Hypothesis_Status
 
   SMESH_Hypothesis::Hypothesis_Status aux_ret, ret = SMESH_Hypothesis::HYP_OK;
 
-  int dim = SMESH_Gen::GetShapeDim(_subShape);
+  SMESHDS_Mesh* meshDS =_father->GetMeshDS();
+  SMESH_Gen*    gen    =_father->GetGen();
+  SMESH_Algo*   algo   = 0;
 
-  if (dim < 1)
+  if (_subShape.ShapeType() == TopAbs_VERTEX )
   {
-    _algoState = HYP_OK;
-    if (event == ADD_HYP || event == ADD_ALGO)
-      return SMESH_Hypothesis::HYP_BAD_DIM; // do not allow to assign any hyp
-    else
-      return SMESH_Hypothesis::HYP_OK;
+    if ( anHyp->GetDim() != 0) {
+      if (event == ADD_HYP || event == ADD_ALGO)
+        return SMESH_Hypothesis::HYP_BAD_DIM;
+      else
+        return SMESH_Hypothesis::HYP_OK;
+    }
+    // 0D hypothesis
+    else if ( _algoState == HYP_OK ) { // update default _algoState
+      _algoState = NO_ALGO;
+      algo = gen->GetAlgo(*_father, _subShape);
+      if ( algo ) {
+        _algoState = MISSING_HYP;
+        if ( algo->CheckHypothesis(*_father,_subShape, aux_ret))
+          _algoState = HYP_OK;
+      }
+    }
   }
 
-  SMESH_Gen* gen   =_father->GetGen();
-  SMESH_Algo* algo = 0;
   int oldAlgoState = _algoState;
-  bool modifiedHyp = false;  // if set to true, force event MODIF_ALGO_STATE
-                             // in ComputeStateEngine
+  bool modifiedHyp = (event == MODIF_HYP);  // if set to true, force event MODIF_ALGO_STATE
+
+  bool isApplicableHyp = IsApplicableHypotesis( anHyp );
 
-  // ----------------------
-  // check mesh conformity
-  // ----------------------
   if (event == ADD_ALGO || event == ADD_FATHER_ALGO)
   {
-    if (IsApplicableHypotesis( anHyp ) &&
-        !_father->IsNotConformAllowed() &&
-        !IsConform( static_cast< SMESH_Algo* >( anHyp )))
+    // -------------------------------------------
+    // check if a shape needed by algo is present
+    // -------------------------------------------
+    algo = static_cast< SMESH_Algo* >( anHyp );
+    if ( !_father->HasShapeToMesh() && algo->NeedShape() )
+      return SMESH_Hypothesis::HYP_BAD_GEOMETRY;
+    // ----------------------
+    // check mesh conformity
+    // ----------------------
+    if (isApplicableHyp && !_father->IsNotConformAllowed() && !IsConform( algo ))
       return SMESH_Hypothesis::HYP_NOTCONFORM;
   }
 
@@ -556,13 +595,13 @@ SMESH_Hypothesis::Hypothesis_Status
   // ----------------------------------
   if (event == ADD_HYP || event == ADD_ALGO)
   {
-    if ( ! CanAddHypothesis( anHyp ))
+    if ( ! CanAddHypothesis( anHyp )) // check dimension
       return SMESH_Hypothesis::HYP_BAD_DIM;
 
     if ( /*!anHyp->IsAuxiliary() &&*/ GetSimilarAttached( _subShape, anHyp ) )
       return SMESH_Hypothesis::HYP_ALREADY_EXIST;
 
-    if ( !_meshDS->AddHypothesis(_subShape, anHyp))
+    if ( !meshDS->AddHypothesis(_subShape, anHyp))
       return SMESH_Hypothesis::HYP_ALREADY_EXIST;
 
     // Serve Propagation of 1D hypothesis
@@ -614,7 +653,7 @@ SMESH_Hypothesis::Hypothesis_Status
   // --------------------------
   if (event == REMOVE_HYP || event == REMOVE_ALGO)
   {
-    if (!_meshDS->RemoveHypothesis(_subShape, anHyp))
+    if (!meshDS->RemoveHypothesis(_subShape, anHyp))
       return SMESH_Hypothesis::HYP_OK; // nothing changes
 
     // Serve Propagation of 1D hypothesis
@@ -673,7 +712,7 @@ SMESH_Hypothesis::Hypothesis_Status
   // ------------------
   // analyse algo state
   // ------------------
-  if (!IsApplicableHypotesis( anHyp ))
+  if (!isApplicableHyp)
     return ret; // not applicable hypotheses do not change algo state
 
   switch (_algoState)
@@ -691,7 +730,7 @@ SMESH_Hypothesis::Hypothesis_Status
       if (algo->CheckHypothesis((*_father),_subShape, aux_ret))
         SetAlgoState(HYP_OK);
       else if ( algo->IsStatusFatal( aux_ret )) {
-        _meshDS->RemoveHypothesis(_subShape, anHyp);
+        meshDS->RemoveHypothesis(_subShape, anHyp);
         ret = aux_ret;
       }
       else
@@ -699,9 +738,7 @@ SMESH_Hypothesis::Hypothesis_Status
       break;
     }
     case REMOVE_HYP:
-      break;
     case REMOVE_ALGO:
-      break;
     case ADD_FATHER_HYP:
       break;
     case ADD_FATHER_ALGO: {    // Algo just added in father
@@ -728,6 +765,7 @@ SMESH_Hypothesis::Hypothesis_Status
       }
       break;
     }
+    case MODIF_HYP: break;
     default:
       ASSERT(0);
       break;
@@ -745,10 +783,10 @@ SMESH_Hypothesis::Hypothesis_Status
       if ( algo->CheckHypothesis((*_father),_subShape, ret ))
         SetAlgoState(HYP_OK);
       if (SMESH_Hypothesis::IsStatusFatal( ret ))
-        _meshDS->RemoveHypothesis(_subShape, anHyp);
+        meshDS->RemoveHypothesis(_subShape, anHyp);
       else if (!_father->IsUsedHypothesis( anHyp, this ))
       {
-        _meshDS->RemoveHypothesis(_subShape, anHyp);
+        meshDS->RemoveHypothesis(_subShape, anHyp);
         ret = SMESH_Hypothesis::HYP_INCOMPATIBLE;
       }
       break;
@@ -759,7 +797,7 @@ SMESH_Hypothesis::Hypothesis_Status
       if ( algo->CheckHypothesis((*_father),_subShape, aux_ret ))// ignore hyp status
         SetAlgoState(HYP_OK);
       else if ( algo->IsStatusFatal( aux_ret )) {
-        _meshDS->RemoveHypothesis(_subShape, anHyp);
+        meshDS->RemoveHypothesis(_subShape, anHyp);
         ret = aux_ret;
       }
       else
@@ -783,6 +821,7 @@ SMESH_Hypothesis::Hypothesis_Status
       }
       break;
     }
+    case MODIF_HYP: // assigned hypothesis value may become good
     case ADD_FATHER_HYP: {
       algo = gen->GetAlgo((*_father), _subShape);
       ASSERT(algo);
@@ -846,7 +885,7 @@ SMESH_Hypothesis::Hypothesis_Status
       if (SMESH_Hypothesis::IsStatusFatal( ret ))
       {
         MESSAGE("do not add extra hypothesis");
-        _meshDS->RemoveHypothesis(_subShape, anHyp);
+        meshDS->RemoveHypothesis(_subShape, anHyp);
       }
       else
       {
@@ -899,6 +938,7 @@ SMESH_Hypothesis::Hypothesis_Status
       }
       break;
     }
+    case MODIF_HYP: // hypothesis value may become bad
     case ADD_FATHER_HYP: {  // new father hypothesis ?
       algo = gen->GetAlgo((*_father), _subShape);
       ASSERT(algo);
@@ -973,7 +1013,7 @@ SMESH_Hypothesis::Hypothesis_Status
     break;
   }
 
-  // detect algorithm hidding
+  // detect algorithm hiding
   //
   if ( ret == SMESH_Hypothesis::HYP_OK &&
        ( event == ADD_ALGO || event == ADD_FATHER_ALGO ) &&
@@ -996,22 +1036,28 @@ SMESH_Hypothesis::Hypothesis_Status
     }
   }
 
-  if ( _algoState != oldAlgoState )
-  {
-    if (_algoState == HYP_OK )
-      algo->SetEventListener( this );
-    if ( oldAlgoState == HYP_OK )
-      DeleteOwnListeners();
-  }
+  bool stateChange = ( _algoState != oldAlgoState );
+
+  if ( stateChange && _algoState == HYP_OK ) // hyp becomes OK
+    algo->SetEventListener( this );
+
   NotifyListenersOnEvent( event, ALGO_EVENT, anHyp );
 
-  if (_algoState != oldAlgoState || modifiedHyp)
+  if ( stateChange && oldAlgoState == HYP_OK ) { // hyp becomes KO
+    DeleteOwnListeners();
+    if (_subShape.ShapeType() == TopAbs_VERTEX ) {
+      // restore default states
+      _algoState = HYP_OK;
+      _computeState = READY_TO_COMPUTE;
+    }
+  }
+
+  if (stateChange || modifiedHyp)
     ComputeStateEngine(MODIF_ALGO_STATE);
 
   return ret;
 }
 
-
 //=======================================================================
 //function : IsConform
 //purpose  : check if a conform mesh will be produced by the Algo
@@ -1085,20 +1131,15 @@ SMESH_Hypothesis::Hypothesis_Status
   SMESH_subMesh::SubMeshesAlgoStateEngine(int event,
                                           SMESH_Hypothesis * anHyp)
 {
-  //MESSAGE("SMESH_subMesh::SubMeshesAlgoStateEngine");
   SMESH_Hypothesis::Hypothesis_Status ret = SMESH_Hypothesis::HYP_OK;
   //EAP: a wire (dim==1) should notify edges (dim==1)
   //EAP: int dim = SMESH_Gen::GetShapeDim(_subShape);
   if (_subShape.ShapeType() < TopAbs_EDGE ) // wire,face etc
   {
-    const map < int, SMESH_subMesh * >&subMeshes = DependsOn();
-
-    map < int, SMESH_subMesh * >::const_iterator itsub;
-    for (itsub = subMeshes.begin(); itsub != subMeshes.end(); itsub++)
-    {
-      SMESH_subMesh *sm = (*itsub).second;
+    SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,false);
+    while ( smIt->more() ) {
       SMESH_Hypothesis::Hypothesis_Status ret2 =
-        sm->AlgoStateEngine(event, anHyp);
+        smIt->next()->AlgoStateEngine(event, anHyp);
       if ( ret2 > ret )
         ret = ret2;
     }
@@ -1114,15 +1155,9 @@ SMESH_Hypothesis::Hypothesis_Status
 
 void SMESH_subMesh::CleanDependsOn()
 {
-  //MESSAGE("SMESH_subMesh::CleanDependsOn");
-
-  const map < int, SMESH_subMesh * >&dependson = DependsOn();
-  map < int, SMESH_subMesh * >::const_iterator its;
-  for (its = dependson.begin(); its != dependson.end(); its++)
-  {
-    SMESH_subMesh *sm = (*its).second;
-    sm->ComputeStateEngine(CLEAN);
-  }
+  SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,false);
+  while ( smIt->more() )
+    smIt->next()->ComputeStateEngine(CLEAN);
 }
 
 //=============================================================================
@@ -1201,8 +1236,10 @@ static void cleanSubMesh( SMESH_subMesh * subMesh )
       while (itn->more()) {
         const SMDS_MeshNode * node = itn->next();
         //MESSAGE( " RM node: "<<node->GetID());
-        //meshDS->RemoveNode(node);
-        meshDS->RemoveFreeNode(node, subMeshDS);
+        if ( node->NbInverseNodes() == 0 )
+          meshDS->RemoveFreeNode(node, subMeshDS);
+        else // for StdMeshers_CompositeSegment_1D: node in one submesh, edge in another
+          meshDS->RemoveNode(node);
       }
     }
   }
@@ -1216,25 +1253,36 @@ static void cleanSubMesh( SMESH_subMesh * subMesh )
 
 bool SMESH_subMesh::ComputeStateEngine(int event)
 {
+  _computeError.reset();
+
   //MESSAGE("SMESH_subMesh::ComputeStateEngine");
   //SCRUTE(_computeState);
   //SCRUTE(event);
 
-  int dim = SMESH_Gen::GetShapeDim(_subShape);
-
-  if (dim < 1)
+  if (_subShape.ShapeType() == TopAbs_VERTEX)
   {
-    if ( IsMeshComputed() )
+    _computeState = READY_TO_COMPUTE;
+    SMESHDS_SubMesh* smDS = GetSubMeshDS();
+    if ( smDS && smDS->NbNodes() ) {
       _computeState = COMPUTE_OK;
-    else
-      _computeState = READY_TO_COMPUTE;
+    }
+    else if ( event == COMPUTE && !_alwaysComputed ) {
+      const TopoDS_Vertex & V = TopoDS::Vertex( _subShape );
+      gp_Pnt P = BRep_Tool::Pnt(V);
+      if ( SMDS_MeshNode * n = _father->GetMeshDS()->AddNode(P.X(), P.Y(), P.Z()) ) {
+        _father->GetMeshDS()->SetNodeOnVertex(n,_Id);
+        _computeState = COMPUTE_OK;
+      }
+    }
+    if ( event == MODIF_ALGO_STATE )
+      CleanDependants();
     return true;
   }
   SMESH_Gen *gen = _father->GetGen();
   SMESH_Algo *algo = 0;
   bool ret = true;
   SMESH_Hypothesis::Hypothesis_Status hyp_status;
-  algo_state oldAlgoState = (algo_state) GetAlgoState();
+  //algo_state oldAlgoState = (algo_state) GetAlgoState();
 
   switch (_computeState)
   {
@@ -1244,21 +1292,12 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
   case NOT_READY:
     switch (event)
     {
-    case MODIF_HYP:
     case MODIF_ALGO_STATE:
       algo = gen->GetAlgo((*_father), _subShape);
       if (algo && !algo->NeedDescretBoundary())
         CleanDependsOn(); // clean sub-meshes with event CLEAN
-      if (algo)
-      {
-        ret = algo->CheckHypothesis((*_father), _subShape, hyp_status);
-        if (ret)
-          _computeState = READY_TO_COMPUTE;
-      }
-      if ( _computeState == READY_TO_COMPUTE )
-          SetAlgoState(HYP_OK);
-      else
-          SetAlgoState(MISSING_HYP);
+      if ( _algoState == HYP_OK )
+        _computeState = READY_TO_COMPUTE;
       break;
     case COMPUTE:              // nothing to do
       break;
@@ -1269,7 +1308,7 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
     case SUBMESH_COMPUTED:     // nothing to do
       break;
     case SUBMESH_RESTORED:
-      ComputeSubMeshStateEngine( CHECK_COMPUTE_STATE );
+      ComputeSubMeshStateEngine( SUBMESH_RESTORED );
       break;
     case MESH_ENTITY_REMOVED:
       break;
@@ -1288,21 +1327,15 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
   case READY_TO_COMPUTE:
     switch (event)
     {
-    case MODIF_HYP:
     case MODIF_ALGO_STATE:
-      algo = gen->GetAlgo((*_father), _subShape);
-      if (algo && !algo->NeedDescretBoundary())
-        CleanDependsOn(); // clean sub-meshes with event CLEAN
       _computeState = NOT_READY;
+      algo = gen->GetAlgo((*_father), _subShape);
       if (algo)
       {
-        ret = algo->CheckHypothesis((*_father), _subShape, hyp_status);
-        if (ret) {
-          SetAlgoState(HYP_OK); // it might be KO if BAD_PARAM_VALUE
+        if (!algo->NeedDescretBoundary())
+          CleanDependsOn(); // clean sub-meshes with event CLEAN
+        if ( _algoState == HYP_OK )
           _computeState = READY_TO_COMPUTE;
-        }
-        else
-          SetAlgoState(MISSING_HYP);
       }
       break;
     case COMPUTE:
@@ -1318,60 +1351,95 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
           break;
         }
         // check submeshes needed
-        if (algo->NeedDescretBoundary())
-          ret = SubMeshesComputed();
-        if (!ret)
-        {
-          MESSAGE("Some SubMeshes not computed");
-          _computeState = FAILED_TO_COMPUTE;
-          break;
+        if (_father->HasShapeToMesh() ) {
+          bool subComputed = SubMeshesComputed();
+          ret = ( algo->NeedDescretBoundary() ? subComputed :
+                  ( !subComputed || _father->IsNotConformAllowed() ));
+          if (!ret) {
+            _computeState = FAILED_TO_COMPUTE;
+            if ( !algo->NeedDescretBoundary() )
+              _computeError =
+                SMESH_ComputeError::New(COMPERR_BAD_INPUT_MESH,"Unexpected submesh",algo);
+            break;
+          }
         }
         // compute
         CleanDependants();
         RemoveSubMeshElementsAndNodes();
-       {
-         try {
+        ret = false;
+        _computeState = FAILED_TO_COMPUTE;
+        _computeError = SMESH_ComputeError::New(COMPERR_OK,"",algo);
+        try {
 #if (OCC_VERSION_MAJOR << 16 | OCC_VERSION_MINOR << 8 | OCC_VERSION_MAINTENANCE) > 0x060100
-            OCC_CATCH_SIGNALS;
+          OCC_CATCH_SIGNALS;
 #endif
-           if (!algo->NeedDescretBoundary() && !algo->OnlyUnaryInput())
-             ret = ApplyToCollection( algo, GetCollection( gen, algo ) );
-           else
-             ret = algo->Compute((*_father), _subShape);
-         }
-         catch (Standard_Failure) {
-           MESSAGE( "Exception in algo->Compute() ");
-           ret = false;
-         }
-       }
+          algo->InitComputeError();
+          if ( !_father->HasShapeToMesh() ) // no shape
+          {
+            SMESH_MesherHelper helper( *_father );
+            helper.SetSubShape( _subShape );
+            helper.SetElementsOnShape( true );
+            ret = algo->Compute(*_father, &helper );
+          }
+          else
+          {
+            if (!algo->NeedDescretBoundary() && !algo->OnlyUnaryInput()) {
+              ret = ApplyToCollection( algo, GetCollection( gen, algo ) );
+              break;
+            }
+            else {
+              ret = algo->Compute((*_father), _subShape);
+            }
+          }
+          if ( !ret )
+            _computeError = algo->GetComputeError();
+        }
+        catch (Standard_Failure& exc) {
+          if ( !_computeError ) _computeError = SMESH_ComputeError::New();
+          _computeError->myName    = COMPERR_OCC_EXCEPTION;
+          _computeError->myComment = exc.GetMessageString();
+        }
+        catch ( SALOME_Exception& S_ex ) {
+          if ( !_computeError ) _computeError = SMESH_ComputeError::New();
+          _computeError->myName    = COMPERR_SLM_EXCEPTION;
+          _computeError->myComment = S_ex.what();
+        }
+        catch ( std::bad_alloc& exc ) {
+          if ( _computeError ) {
+            _computeError->myName    = COMPERR_MEMORY_PB;
+            _computeError->myComment = exc.what();
+          }
+          throw exc;
+        }
+        catch ( std::exception& exc ) {
+          if ( !_computeError ) _computeError = SMESH_ComputeError::New();
+          _computeError->myName    = COMPERR_STD_EXCEPTION;
+          _computeError->myComment = exc.what();
+        }
+        catch ( ... ) {
+          if ( _computeError )
+            _computeError->myName = COMPERR_EXCEPTION;
+        }
+        if ( ret && _computeError && !_computeError->IsOK() ) {
+          ret = false;
+        }
+        if (ret) { // check if anything was built
+          ret = ( GetSubMeshDS() && ( GetSubMeshDS()->NbElements() || GetSubMeshDS()->NbNodes() ));
+        }
         if (!ret)
         {
-          MESSAGE("problem in algo execution: failed to compute");
-          // release ALGO from responsibilty of partially built mesh
-          RemoveSubMeshElementsAndNodes();
-          _computeState = FAILED_TO_COMPUTE;
-          if (!algo->NeedDescretBoundary())
-            UpdateSubMeshState( FAILED_TO_COMPUTE );
-
-#ifdef _DEBUG_
-          // Show vertices location of a failed shape
-          cout << algo->GetName() << " failed on shape with the following vertices:" << endl;
-          TopTools_IndexedMapOfShape vMap;
-          TopExp::MapShapes( _subShape, TopAbs_VERTEX, vMap );
-          for ( int iv = 1; iv <= vMap.Extent(); ++iv ) {
-            gp_Pnt P( BRep_Tool::Pnt( TopoDS::Vertex( vMap( iv ) )));
-            cout << P.X() << " " << P.Y() << " " << P.Z() << " " << endl;
-          }
-#endif
-          break;
+          // Set _computeError
+          if ( !_computeError )
+            _computeError = SMESH_ComputeError::New();
+          if ( _computeError->IsOK() )
+            _computeError->myName = COMPERR_ALGO_FAILED;
         }
         else
         {
-          _computeState = COMPUTE_OK;
+          _computeError.reset();
           UpdateDependantsState( SUBMESH_COMPUTED ); // send event SUBMESH_COMPUTED
-          if (!algo->NeedDescretBoundary())
-            UpdateSubMeshState( COMPUTE_OK );
         }
+        CheckComputeError( algo );
       }
       break;
     case CLEAN:
@@ -1394,7 +1462,9 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
       // check if a mesh is already computed that may
       // happen after retrieval from a file
       ComputeStateEngine( CHECK_COMPUTE_STATE );
-      ComputeSubMeshStateEngine( CHECK_COMPUTE_STATE );
+      ComputeSubMeshStateEngine( SUBMESH_RESTORED );
+      algo = gen->GetAlgo(*_father, _subShape);
+      if (algo) algo->SubmeshRestored( this );
       break;
     case MESH_ENTITY_REMOVED:
       break;
@@ -1413,7 +1483,6 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
   case COMPUTE_OK:
     switch (event)
     {
-    case MODIF_HYP:
     case MODIF_ALGO_STATE:
       ComputeStateEngine( CLEAN );
       algo = gen->GetAlgo((*_father), _subShape);
@@ -1426,21 +1495,16 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
       CleanDependants();  // clean sub-meshes, dependant on this one, with event CLEAN
       RemoveSubMeshElementsAndNodes();
       _computeState = NOT_READY;
-      algo = gen->GetAlgo((*_father), _subShape);
-      if (algo)
-      {
-        ret = algo->CheckHypothesis((*_father), _subShape, hyp_status);
-        if (ret)
-          _computeState = READY_TO_COMPUTE;
-        else
-          SetAlgoState(MISSING_HYP);
-      }
+      if ( _algoState == HYP_OK )
+        _computeState = READY_TO_COMPUTE;
       break;
     case SUBMESH_COMPUTED:      // nothing to do
       break;
     case SUBMESH_RESTORED:
       ComputeStateEngine( CHECK_COMPUTE_STATE );
-      ComputeSubMeshStateEngine( CHECK_COMPUTE_STATE );
+      ComputeSubMeshStateEngine( SUBMESH_RESTORED );
+      algo = gen->GetAlgo(*_father, _subShape);
+      if (algo) algo->SubmeshRestored( this );
       break;
     case MESH_ENTITY_REMOVED:
       UpdateDependantsState( CHECK_COMPUTE_STATE );
@@ -1465,12 +1529,6 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
   case FAILED_TO_COMPUTE:
     switch (event)
     {
-    case MODIF_HYP:
-      if (_algoState == HYP_OK)
-        _computeState = READY_TO_COMPUTE;
-      else
-        _computeState = NOT_READY;
-      break;
     case MODIF_ALGO_STATE:
       if (_algoState == HYP_OK)
         _computeState = READY_TO_COMPUTE;
@@ -1482,10 +1540,6 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
     case CLEAN:
       CleanDependants(); // submeshes dependent on me should be cleaned as well
       RemoveSubMeshElementsAndNodes();
-      if (_algoState == HYP_OK)
-        _computeState = READY_TO_COMPUTE;
-      else
-        _computeState = NOT_READY;
       break;
     case SUBMESH_COMPUTED:      // allow retry compute
       if (_algoState == HYP_OK)
@@ -1494,7 +1548,7 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
         _computeState = NOT_READY;
       break;
     case SUBMESH_RESTORED:
-      ComputeSubMeshStateEngine( CHECK_COMPUTE_STATE );
+      ComputeSubMeshStateEngine( SUBMESH_RESTORED );
       break;
     case MESH_ENTITY_REMOVED:
       break;
@@ -1519,19 +1573,64 @@ bool SMESH_subMesh::ComputeStateEngine(int event)
     break;
   }
 
-  if ( _algoState != oldAlgoState || event == MODIF_HYP )
-  {
-    if ( oldAlgoState == HYP_OK )
-      DeleteOwnListeners();
-    if (_algoState == HYP_OK && algo )
-      algo->SetEventListener( this );
-  }
   NotifyListenersOnEvent( event, COMPUTE_EVENT );
 
-  //SCRUTE(_computeState);
   return ret;
 }
 
+//=======================================================================
+/*!
+ * \brief Update compute_state by _computeError
+ */
+//=======================================================================
+
+bool SMESH_subMesh::CheckComputeError(SMESH_Algo* theAlgo)
+{
+  bool noErrors = ( !_computeError || _computeError->IsOK() );
+  if ( !noErrors )
+  {
+    if ( !_computeError->myAlgo )
+      _computeError->myAlgo = theAlgo;
+
+    // Show error
+    SMESH_Comment text;
+    text << theAlgo->GetName() << " failed on subshape " << _Id << " with error ";
+    if (_computeError->IsCommon() )
+      text << _computeError->CommonName();
+    else
+      text << _computeError->myName;
+    if ( _computeError->myComment.size() > 0 )
+      text << " \"" << _computeError->myComment << "\"";
+
+#ifdef _DEBUG_
+    cout << text << endl;
+    // Show vertices location of a failed shape
+    cout << "Subshape vertices (first 10):" << endl;
+    TopTools_IndexedMapOfShape vMap;
+    TopExp::MapShapes( _subShape, TopAbs_VERTEX, vMap );
+    for ( int iv = 1; iv <= vMap.Extent() && iv < 11; ++iv ) {
+      gp_Pnt P( BRep_Tool::Pnt( TopoDS::Vertex( vMap( iv ) )));
+      cout << P.X() << " " << P.Y() << " " << P.Z() << " " << endl;
+    }
+#else
+    INFOS( text );
+#endif
+    _computeState = FAILED_TO_COMPUTE;
+  }
+  else
+  {
+    _computeState = COMPUTE_OK;
+  }
+  // Check state of submeshes
+  if ( !theAlgo->NeedDescretBoundary() && theAlgo->OnlyUnaryInput() ) {
+    SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,false);
+    while ( smIt->more() )
+      if ( !smIt->next()->CheckComputeError( theAlgo ))
+        noErrors = false;
+  }
+  return noErrors;
+}
+
 //=======================================================================
 //function : ApplyToCollection
 //purpose  : Apply theAlgo to all subshapes in theCollection
@@ -1543,32 +1642,32 @@ bool SMESH_subMesh::ApplyToCollection (SMESH_Algo*         theAlgo,
   MESSAGE("SMESH_subMesh::ApplyToCollection");
   ASSERT ( !theAlgo->NeedDescretBoundary() );
 
-  bool ret = false;
+  if ( _computeError )
+    _computeError->myName = COMPERR_OK;
 
-
-  ret = theAlgo->Compute( *_father, theCollection );
+  bool ok = theAlgo->Compute( *_father, theCollection );
 
   // set _computeState of subshapes
+  bool localOK = true;
   TopExp_Explorer anExplorer( theCollection, _subShape.ShapeType() );
   for ( ; anExplorer.More(); anExplorer.Next() )
   {
-    const TopoDS_Shape& aSubShape = anExplorer.Current();
-    SMESH_subMesh* subMesh = _father->GetSubMeshContaining( aSubShape );
-    if ( subMesh )
+    if ( SMESH_subMesh* subMesh = _father->GetSubMeshContaining( anExplorer.Current() ))
     {
-      if (ret)
-      {
-        subMesh->_computeState = COMPUTE_OK;
-        subMesh->UpdateDependantsState( SUBMESH_COMPUTED );
-        subMesh->UpdateSubMeshState( COMPUTE_OK );
-      }
+      if ( !subMesh->CheckComputeError( theAlgo ))
+        localOK = false;
       else
-      {
-        subMesh->_computeState = FAILED_TO_COMPUTE;
-      }
+        subMesh->UpdateDependantsState( SUBMESH_COMPUTED );
     }
   }
-  return ret;
+  if ( !ok && localOK ) { // KO but error set to none submesh
+    _computeError = theAlgo->GetComputeError();
+    if ( _computeError->IsOK() )
+      _computeError = SMESH_ComputeError::New(COMPERR_ALGO_FAILED);
+    CheckComputeError( theAlgo );
+  }
+
+  return true;
 }
 
 
@@ -1579,13 +1678,9 @@ bool SMESH_subMesh::ApplyToCollection (SMESH_Algo*         theAlgo,
 
 void SMESH_subMesh::UpdateSubMeshState(const compute_state theState)
 {
-  const map<int, SMESH_subMesh*>& smMap = DependsOn();
-  map<int, SMESH_subMesh*>::const_iterator itsub;
-  for (itsub = smMap.begin(); itsub != smMap.end(); itsub++)
-  {
-    SMESH_subMesh* sm = (*itsub).second;
-    sm->_computeState = theState;
-  }
+  SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,false);
+  while ( smIt->more() )
+    smIt->next()->_computeState = theState;
 }
 
 //=======================================================================
@@ -1595,13 +1690,9 @@ void SMESH_subMesh::UpdateSubMeshState(const compute_state theState)
 
 void SMESH_subMesh::ComputeSubMeshStateEngine(int event)
 {
-  const map<int, SMESH_subMesh*>& smMap = DependsOn();
-  map<int, SMESH_subMesh*>::const_iterator itsub;
-  for (itsub = smMap.begin(); itsub != smMap.end(); itsub++)
-  {
-    SMESH_subMesh* sm = (*itsub).second;
-    sm->ComputeStateEngine(event);
-  }
+  SMESH_subMeshIteratorPtr smIt = getDependsOnIterator(false,false);
+  while ( smIt->more() )
+    smIt->next()->ComputeStateEngine(event);
 }
 
 //=======================================================================
@@ -1678,37 +1769,6 @@ void SMESH_subMesh::RemoveSubMeshElementsAndNodes()
   }
 }
 
-//=======================================================================
-//function : IsMeshComputed
-//purpose  : check if _subMeshDS contains mesh elements
-//=======================================================================
-
-bool SMESH_subMesh::IsMeshComputed() const
-{
-  // algo may bind a submesh not to _subShape, eg 3D algo
-  // sets nodes on SHELL while _subShape may be SOLID
-
-  int dim = SMESH_Gen::GetShapeDim( _subShape );
-  int type = _subShape.ShapeType();
-  for ( ; type <= TopAbs_VERTEX; type++) {
-    if ( dim == SMESH_Gen::GetShapeDim( (TopAbs_ShapeEnum) type ))
-    {
-      TopExp_Explorer exp( _subShape, (TopAbs_ShapeEnum) type );
-      for ( ; exp.More(); exp.Next() )
-      {
-        SMESHDS_SubMesh * smDS = _meshDS->MeshElements( exp.Current() );
-        if ( smDS && ( smDS->NbElements() || smDS->NbNodes()))
-          return true;
-      }
-    }
-    else
-      break;
-  }
-
-  return false;
-}
-
-
 //=======================================================================
 //function : GetCollection
 //purpose  : return a shape containing all sub-shapes of the MainShape that can be
@@ -1741,14 +1801,17 @@ TopoDS_Shape SMESH_subMesh::GetCollection(SMESH_Gen * theGen, SMESH_Algo* theAlg
   {
     const TopoDS_Shape& S = anExplorer.Current();
     SMESH_subMesh* subMesh = _father->GetSubMesh( S );
-    SMESH_Algo* anAlgo = theGen->GetAlgo( *_father, S );
-
-    if (subMesh->GetComputeState() == READY_TO_COMPUTE &&
-        anAlgo == theAlgo &&
-        anAlgo->GetUsedHypothesis( *_father, S, ignoreAuxiliaryHyps ) == aUsedHyp)
+    if ( subMesh == this )
     {
       aBuilder.Add( aCompound, S );
     }
+    else if ( subMesh->GetComputeState() == READY_TO_COMPUTE )
+    {
+      SMESH_Algo* anAlgo = theGen->GetAlgo( *_father, S );
+      if (anAlgo == theAlgo &&
+          anAlgo->GetUsedHypothesis( *_father, S, ignoreAuxiliaryHyps ) == aUsedHyp)
+        aBuilder.Add( aCompound, S );
+    }
   }
 
   return aCompound;
@@ -1859,7 +1922,15 @@ void SMESH_subMesh::SetEventListener(EventListener*     listener,
 
 void SMESH_subMesh::SetEventListener(EventListener* listener, EventListenerData* data)
 {
-  myEventListeners.insert( make_pair( listener, data ));
+  map< EventListener*, EventListenerData* >::iterator l_d =
+    myEventListeners.find( listener );
+  if ( l_d != myEventListeners.end() ) {
+    if ( l_d->second && l_d->second->IsDeletable() )
+      delete l_d->second;
+    l_d->second = data;
+  }
+  else 
+    myEventListeners.insert( make_pair( listener, data ));
 }
 
 //================================================================================
@@ -1911,8 +1982,8 @@ void SMESH_subMesh::DeleteEventListener(EventListener* listener)
   map< EventListener*, EventListenerData* >::iterator l_d =
     myEventListeners.find( listener );
   if ( l_d != myEventListeners.end() ) {
-    if ( l_d->first->IsDeletable() ) delete l_d->first;
-    if ( l_d->second->IsDeletable() ) delete l_d->second;
+    if ( l_d->first  && l_d->first->IsDeletable() )  delete l_d->first;
+    if ( l_d->second && l_d->second->IsDeletable() ) delete l_d->second;
     myEventListeners.erase( l_d );
   }
 }
@@ -1950,7 +2021,7 @@ void SMESH_subMeshEventListener::ProcessEvent(const int          event,
                                               const int          eventType,
                                               SMESH_subMesh*     subMesh,
                                               EventListenerData* data,
-                                              SMESH_Hypothesis*  /*hyp*/)
+                                              const SMESH_Hypothesis*  /*hyp*/)
 {
   if ( data && !data->mySubMeshes.empty() &&
        eventType == SMESH_subMesh::COMPUTE_EVENT)
@@ -1968,3 +2039,69 @@ void SMESH_subMeshEventListener::ProcessEvent(const int          event,
     }
   }
 }
+
+namespace {
+
+  //================================================================================
+  /*!
+   * \brief Iterator over submeshes and optionally prepended or appended one
+   */
+  //================================================================================
+
+  struct _Iterator : public SMDS_Iterator<SMESH_subMesh*>
+  {
+    _Iterator(SMDS_Iterator<SMESH_subMesh*>* subIt,
+              SMESH_subMesh*                 prepend,
+              SMESH_subMesh*                 append): myIt(subIt),myAppend(append)
+    {
+      myCur = prepend ? prepend : myIt->more() ? myIt->next() : 0;
+    }
+    /// Return true if and only if there are other object in this iterator
+    virtual bool more()
+    {
+      return myCur;
+    }
+    /// Return the current object and step to the next one
+    virtual SMESH_subMesh* next()
+    {
+      SMESH_subMesh* res = myCur;
+      if ( myIt->more() ) { myCur = myIt->next(); }
+      else                { myCur = myAppend; myAppend = 0; }
+      return res;
+    }
+    /// ~
+    ~_Iterator()
+    { delete myIt; }
+    ///
+    SMESH_subMesh                 *myAppend, *myCur;
+    SMDS_Iterator<SMESH_subMesh*> *myIt;
+  };
+}
+
+//================================================================================
+/*!
+ * \brief  Return iterator on the submeshes this one depends on
+  * \param includeSelf - this submesh to be returned also
+  * \param reverse - if true, complex shape submeshes go first
+ */
+//================================================================================
+
+SMESH_subMeshIteratorPtr SMESH_subMesh::getDependsOnIterator(const bool includeSelf,
+                                                             const bool reverse)
+{
+  SMESH_subMesh *prepend=0, *append=0;
+  if ( includeSelf ) {
+    if ( reverse ) prepend = this;
+    else            append = this;
+  }
+  typedef map < int, SMESH_subMesh * > TMap;
+  if ( reverse )
+  {
+    return SMESH_subMeshIteratorPtr
+      ( new _Iterator( new SMDS_mapReverseIterator<TMap>( DependsOn() ), prepend, append ));
+  }
+  {
+    return SMESH_subMeshIteratorPtr
+      ( new _Iterator( new SMDS_mapIterator<TMap>( DependsOn() ), prepend, append ));
+  }
+}