From: eap <eap@opencascade.com>
Date: Thu, 22 Oct 2020 08:33:25 +0000 (+0300)
Subject: bos #20244 [CEA 20227] OCCT SIGSEGV - Cutting of quadrangles
X-Git-Tag: V9_6_0rc1~3
X-Git-Url: http://git.salome-platform.org/gitweb/?a=commitdiff_plain;h=76b3528b3f9351b8ff39174b480eef799efa931b;p=modules%2Fsmesh.git

bos #20244 [CEA 20227] OCCT SIGSEGV - Cutting of quadrangles
---

diff --git a/src/SMESH/SMESH_MeshEditor.cxx b/src/SMESH/SMESH_MeshEditor.cxx
index ae3b70321..1d679c2bc 100644
--- a/src/SMESH/SMESH_MeshEditor.cxx
+++ b/src/SMESH/SMESH_MeshEditor.cxx
@@ -1504,9 +1504,12 @@ void SMESH_MeshEditor::QuadTo4Tri (TIDSortedElemSet & theElems)
   SMESH_MesherHelper helper( *GetMesh() );
   helper.SetElementsOnShape( true );
 
-  SMDS_ElemIteratorPtr faceIt;
-  if ( theElems.empty() ) faceIt = GetMeshDS()->elementsIterator(SMDSAbs_Face);
-  else                    faceIt = SMESHUtils::elemSetIterator( theElems );
+  // get standalone groups of faces
+  vector< SMDS_MeshGroup* > allFaceGroups, faceGroups;
+  for ( SMESHDS_GroupBase* grBase : GetMeshDS()->GetGroups() )
+    if ( SMESHDS_Group* group = dynamic_cast<SMESHDS_Group*>( grBase ))
+      if ( group->GetType() == SMDSAbs_Face && !group->IsEmpty() )
+        allFaceGroups.push_back( & group->SMDSGroup() );
 
   bool   checkUV;
   gp_XY  uv [9]; uv[8] = gp_XY(0,0);
@@ -1517,6 +1520,10 @@ void SMESH_MeshEditor::QuadTo4Tri (TIDSortedElemSet & theElems)
   Handle(Geom_Surface)           surface;
   TopLoc_Location                loc;
 
+  SMDS_ElemIteratorPtr faceIt;
+  if ( theElems.empty() ) faceIt = GetMeshDS()->elementsIterator(SMDSAbs_Face);
+  else                    faceIt = SMESHUtils::elemSetIterator( theElems );
+
   while ( faceIt->more() )
   {
     const SMDS_MeshElement* quad = faceIt->next();
@@ -1593,13 +1600,19 @@ void SMESH_MeshEditor::QuadTo4Tri (TIDSortedElemSet & theElems)
       myLastCreatedNodes.push_back( nCentral );
     }
 
-    // create 4 triangles
-
     helper.SetIsQuadratic  ( nodes.size() > 4 );
     helper.SetIsBiQuadratic( nodes.size() == 9 );
     if ( helper.GetIsQuadratic() )
       helper.AddTLinks( static_cast< const SMDS_MeshFace*>( quad ));
 
+    // select groups to update
+    faceGroups.clear();
+    for ( SMDS_MeshGroup* group : allFaceGroups )
+      if ( group->Remove( quad ))
+        faceGroups.push_back( group );
+
+    // create 4 triangles
+
     GetMeshDS()->RemoveFreeElement( quad, subMeshDS, /*fromGroups=*/false );
 
     for ( int i = 0; i < 4; ++i )
@@ -1607,8 +1620,9 @@ void SMESH_MeshEditor::QuadTo4Tri (TIDSortedElemSet & theElems)
       SMDS_MeshElement* tria = helper.AddFace( nodes[ i ],
                                                nodes[(i+1)%4],
                                                nCentral );
-      ReplaceElemInGroups( tria, quad, GetMeshDS() );
       myLastCreatedElems.push_back( tria );
+      for ( SMDS_MeshGroup* group : faceGroups )
+        group->Add( tria );
     }
   }
 }
diff --git a/src/SMESH_I/SMESH_MeshEditor_i.cxx b/src/SMESH_I/SMESH_MeshEditor_i.cxx
index 16cc20053..3330950a2 100644
--- a/src/SMESH_I/SMESH_MeshEditor_i.cxx
+++ b/src/SMESH_I/SMESH_MeshEditor_i.cxx
@@ -1966,6 +1966,8 @@ void SMESH_MeshEditor_i::QuadTo4Tri (SMESH::SMESH_IDSource_ptr theObject)
   getEditor().QuadTo4Tri( faces );
   TPythonDump() << this << ".QuadTo4Tri( " << theObject << " )";
 
+  declareMeshModified( /*isReComputeSafe=*/false );
+
   SMESH_CATCH( SMESH::throwCorbaException );
 }