refine.h

// Copyright (C) 2010-2023 Garth N. Wells
//
// This file is part of DOLFINx (https://www.fenicsproject.org)
//
// SPDX-License-Identifier:    LGPL-3.0-or-later
 
#pragma once
 
#include "plaza.h"
#include "refine.h"
#include <dolfinx/common/IndexMap.h>
#include <dolfinx/common/log.h>
#include <dolfinx/mesh/Mesh.h>
#include <dolfinx/mesh/Topology.h>
 
namespace dolfinx::refinement
{
template <std::floating_point T>
mesh::Mesh<T> refine(const mesh::Mesh<T>& mesh, bool redistribute = true)
{
  auto topology = mesh.topology();
  assert(topology);
 
  if (topology->cell_types().size() > 1)
    throw std::runtime_error("Mixed topology not supported");
 
  if (topology->cell_types()[0] != mesh::CellType::triangle
      and topology->cell_types()[0] != mesh::CellType::tetrahedron)
  {
    throw std::runtime_error("Refinement only defined for simplices");
  }
 
  auto [refined_mesh, parent_cell, parent_facet]
      = plaza::refine(mesh, redistribute, plaza::Option::none);
 
  // Report the number of refined cells
  const int D = topology->dim();
  const std::int64_t n0 = topology->index_map(D)->size_global();
  const std::int64_t n1 = refined_mesh.topology()->index_map(D)->size_global();
  LOG(INFO) << "Number of cells increased from " << n0 << " to " << n1 << " ("
            << 100.0 * (static_cast<double>(n1) / static_cast<double>(n0) - 1.0)
            << "%% increase).";
 
  return refined_mesh;
}
 
template <std::floating_point T>
mesh::Mesh<T> refine(const mesh::Mesh<T>& mesh,
                     std::span<const std::int32_t> edges,
                     bool redistribute = true)
{
  auto topology = mesh.topology();
  assert(topology);
 
  if (topology->cell_types().size() > 1)
    throw std::runtime_error("Mixed topology not supported");
  if (topology->cell_types()[0] != mesh::CellType::triangle
      and topology->cell_types()[0] != mesh::CellType::tetrahedron)
  {
    throw std::runtime_error("Refinement only defined for simplices");
  }
 
  auto [refined_mesh, parent_cell, parent_facet]
      = plaza::refine(mesh, edges, redistribute, plaza::Option::none);
 
  // Report the number of refined cells
  const int D = topology->dim();
  const std::int64_t n0 = topology->index_map(D)->size_global();
  const std::int64_t n1 = refined_mesh.topology()->index_map(D)->size_global();
  LOG(INFO) << "Number of cells increased from " << n0 << " to " << n1 << " ("
            << 100.0 * (static_cast<double>(n1) / static_cast<double>(n0) - 1.0)
            << "%% increase).";
 
  return refined_mesh;
}
 
} // namespace dolfinx::refinement