New feature in EB: Add regular coarse levels

This feature could be useful when the EB is so thin that it is only resolved
at the finest level and the usual way of generate coarse levels fails with
multi-cut or multi-value cells. When the EB is fully refined to the finest
level and there is no subcycling, no EB information is really needed at
coarse levels. Note that tagging cut cells for refinement no longer works if
that level has all regular EB.

Src/EB/AMReX_EB2.H

@@ -56,6 +56,7 @@ public:
  [[nodiscard]] virtual const Geometry& getGeometry (const Box& domain) const = 0;
  [[nodiscard]] virtual const Box& coarsestDomain () const = 0;
  virtual void addFineLevels (int num_new_fine_levels) = 0;
+ virtual void addRegularCoarseLevels (int num_new_coarse_levels) = 0;
 
 protected:
  static AMREX_EXPORT Vector<std::unique_ptr<IndexSpace> > m_instance;
@@ -88,6 +89,7 @@ public:
  return m_geom.back().Domain();
  }
  void addFineLevels (int num_new_fine_levels) final;
+ void addRegularCoarseLevels (int num_new_coarse_levels) final;
 
  using F = typename G::FunctionType;
 
@@ -147,6 +149,8 @@ int maxCoarseningLevel (IndexSpace const* ebis, const Geometry& geom);
 
 void addFineLevels (int num_new_fine_levels);
 
+void addRegularCoarseLevels (int num_new_coarse_levels);
+
 }
 
 #endif

Src/EB/AMReX_EB2.cpp

@@ -240,6 +240,14 @@ void addFineLevels (int num_new_fine_levels)
  }
 }
 
+void addRegularCoarseLevels (int num_new_coarse_levels)
+{
+ auto *p = const_cast<IndexSpace*>(TopIndexSpace());
+ if (p) {
+ p->addRegularCoarseLevels(num_new_coarse_levels);
+ }
+}
+
 void
 BuildFromChkptFile (std::string const& fname,
  const Geometry& geom, int required_coarsening_level,

Src/EB/AMReX_EB2_IndexSpaceI.H

@@ -106,3 +106,45 @@ IndexSpaceImp<G>::addFineLevels (int num_new_fine_levels)
  m_domain.insert(m_domain.begin(), fine_isp.m_domain.begin(), fine_isp.m_domain.end());
  m_ngrow.insert(m_ngrow.begin(), fine_isp.m_ngrow.begin(), fine_isp.m_ngrow.end());
 }
+
+template <typename G>
+void
+IndexSpaceImp<G>::addRegularCoarseLevels (int num_new_coarse_levels)
+{
+ if (num_new_coarse_levels <= 0) { return; }
+
+ auto nlevs_old = int(m_gslevel.size());
+ int nlevs_new = nlevs_old + num_new_coarse_levels;
+
+ Vector<GShopLevel<G>> new_gslevel;
+ new_gslevel.reserve(nlevs_new);
+
+ Vector<Geometry> new_geom;
+ new_geom.reserve(nlevs_new);
+
+ Vector<Box> new_domain;
+ new_domain.reserve(nlevs_new);
+
+ Vector<int> new_ngrow;
+ new_ngrow.reserve(nlevs_new);
+
+ for (int ilev = 0; ilev < num_new_coarse_levels; ++ilev) {
+ int rr = 1 << (num_new_coarse_levels-ilev); // 2^(num_new_coarse_levels-ilev)
+ new_geom.push_back(amrex::coarsen(m_geom[0], rr));
+ new_domain.push_back(new_geom.back().Domain());
+ new_ngrow.push_back(m_ngrow[0]);
+ new_gslevel.push_back(GShopLevel<G>::makeAllRegular(this, new_geom.back()));
+ }
+
+ for (int ilev = 0; ilev < nlevs_old; ++ilev) {
+ new_gslevel.emplace_back(std::move(m_gslevel[ilev]));
+ new_geom.push_back (m_geom [ilev]);
+ new_domain.push_back(m_domain[ilev]);
+ new_ngrow.push_back (m_ngrow [ilev]);
+ }
+
+ std::swap(new_gslevel, m_gslevel);
+ std::swap(new_geom , m_geom);
+ std::swap(new_domain , m_domain);
+ std::swap(new_ngrow , m_ngrow);
+}

Src/EB/AMReX_EB2_IndexSpace_STL.H

@@ -34,6 +34,7 @@ public:
  return m_geom.back().Domain();
  }
  void addFineLevels (int num_new_fine_levels) final;
+ void addRegularCoarseLevels (int num_new_coarse_levels) final;
 
 private:
 

Src/EB/AMReX_EB2_IndexSpace_STL.cpp

@@ -88,4 +88,10 @@ IndexSpaceSTL::addFineLevels (int /*num_new_fine_levels*/)
  amrex::Abort("IndexSpaceSTL::addFineLevels: todo");
 }
 
+void
+IndexSpaceSTL::addRegularCoarseLevels (int /*num_new_coarse_levels*/)
+{
+ amrex::Abort("IndexSpaceSTL::addRegularCoarseLevels: todo");
+}
+
 }

Src/EB/AMReX_EB2_IndexSpace_chkpt_file.H

@@ -33,6 +33,7 @@ public:
  return m_geom.back().Domain();
  }
  void addFineLevels (int num_new_fine_levels) final;
+ void addRegularCoarseLevels (int num_new_coarse_levels) final;
 
 private:
 

Src/EB/AMReX_EB2_IndexSpace_chkpt_file.cpp

@@ -83,4 +83,10 @@ IndexSpaceChkptFile::addFineLevels (int /*num_new_fine_levels*/)
  amrex::Abort("IndexSpaceChkptFile::addFineLevels: not supported");
 }
 
+void
+IndexSpaceChkptFile::addRegularCoarseLevels (int /*num_new_coarse_levels*/)
+{
+ amrex::Abort("IndexSpaceChkptFile::addRegularCoarseLevels: not supported");
+}
+
 }

Src/EB/AMReX_EB2_Level.H

@@ -101,6 +101,15 @@ public:
  GShopLevel (IndexSpace const* is, const Geometry& geom);
  void define_fine (G const& gshop, const Geometry& geom,
  int max_grid_size, int ngrow, bool extend_domain_face, int num_crse_opt);
+
+ static GShopLevel<G>
+ makeAllRegular(IndexSpace const* is, const Geometry& geom)
+ {
+ GShopLevel<G> r(is, geom);
+ r.m_allregular = true;
+ r.m_ok = true;
+ return r;
+ }
 };
 
 template <typename G>