Use TextOutArchive to store OCCGeometry in mesh files

libsrc/meshing/basegeom.cpp

@@ -507,6 +507,24 @@ namespace netgen
   
   shared_ptr<NetgenGeometry> GeometryRegisterArray :: LoadFromMeshFile (istream & ist) const
   {
+    if (!ist.good())
+        return nullptr;
+
+    string token;
+    ist >> token;
+    if(token == "TextOutArchive")
+    {
+        NetgenGeometry *geo = nullptr;
+        size_t string_length;
+        ist >> string_length;
+        string buffer(string_length+1, '\0');
+        ist.read(&buffer[0], string_length);
+        auto ss = make_shared<stringstream>(buffer);
+        TextInArchive in(ss);
+        in & geo;
+
+        return shared_ptr<NetgenGeometry>(geo);
+    }
     for (int i = 0; i < Size(); i++)
       {
         NetgenGeometry * hgeom = (*this)[i]->LoadFromMeshFile (ist, token);

libsrc/occ/occgeom.cpp

@@ -1654,6 +1654,18 @@ namespace netgen
       }
   }
 
+  void OCCGeometry :: SaveToMeshFile (ostream & ost) const
+  {
+    auto ss = make_shared<stringstream>();
+    TextOutArchive out(ss);
+    NetgenGeometry *geo = const_cast<OCCGeometry*>(this);
+    out & geo;
+
+    ost << "TextOutArchive" << endl;
+    ost << ss->str().size() << endl;
+    ost << ss->str();
+  }
+
   void OCCGeometry :: DoArchive(Archive& ar)
   {
     if(ar.Output())

libsrc/occ/occgeom.hpp

@@ -380,6 +380,7 @@ namespace netgen
     void FinalizeMesh(Mesh& mesh) const override;
      
     void Save (string filename) const override;
+    void SaveToMeshFile (ostream & /* ost */) const override;
      
     void DoArchive(Archive& ar) override;