Mesh

在CGAL中，Mesh有很多种数据结构，诸如Surface_mesh、Polyhedron_3等等。

Surface_mesh

typedef CGAL::Simple_cartesian<double>          Kernel;
typedef CGAL::Surface_mesh<Kernel::Point_3>     PolygonMesh;

Polyhedron_3

typedef CGAL::Simple_cartesian<double>          Kernel;
typedef CGAL::Polyhedron_3<Kernel>              Polyhedron3;

处理

Mesh的遍历

但它们都是模板类，这模板类的方法都类似，所以可以统一处理。
例如：Mesh的遍历

• 适用于Surface_mesh、Polyhedron_3数据结构

  template<class PolygonMesh>
  Status toGeometry(PolygonMesh& polyhedron, AbstractGeometryPtr& geometry)
  {
    //点
    for (auto vertexIt = polyhedron.vertices_begin(); vertexIt != polyhedron.vertices_end(); ++vertexIt)
    {
        double x = vertexIt->point().x();
        double y = vertexIt->point().y();
        double z = vertexIt->point().z();
        geometry->addVertex(x, y, z); //直接添加，未去重
    }
    //面
    for (auto i = polyhedron.facets_begin(); i != polyhedron.facets_end(); ++i)
    {
        PrimitiveIndices indices; //面索引
        auto j = i->facet_begin();
        // Facets in polyhedral surfaces are at least triangles.
        auto pntNum = CGAL::circulator_size(j);
        do
        {
            std::size_t index = std::distance(polyhedron.vertices_begin(), j->vertex());
            indices.push_back(index);
        } while (++j != i->facet_begin());
        geometry->addPrimitiveIndices(indices);
    }
    return kSuccess;
  }