Modify some classes to functions and struct in DEM (chaos-polymtl#1232)

Description
Some classes should not has been classes but functions or struct.
I modified those classes to a more coherent architechture.
I also gathered all the particle-object contact info structures in one file because it is more convenient that having 3 files for small structs.

Testing
Unit tests have been change according to that.

Former-commit-id: ce0736b

include/dem/particle_wall_contact_info.h → include/dem/contact_info.h

@@ -14,20 +14,29 @@
  * ---------------------------------------------------------------------
  */
 
-#ifndef lethe_particle_wall_contact_info_h
-#define lethe_particle_wall_contact_info_h
+#ifndef lethe_contact_info_h
+#define lethe_contact_info_h
 
 #include <deal.II/base/point.h>
 #include <deal.II/base/tensor.h>
 
 #include <deal.II/particles/particle_iterator.h>
 
+using namespace dealii;
+
 /**
- * @brief This struct handles the information related to the calculation of the
- * particle-wall contact force
+ * @brief Handle the information related to the calculation of the
+ * particle-particle contact force. Notably it is responsible for storing
+ * information that has to be preserved over multiple iterations of a contact,
+ * namely everything related to tangential overlaps
  */
-
-using namespace dealii;
+template <int dim>
+struct particle_particle_contact_info
+{
+  Particles::ParticleIterator<dim> particle_one;
+  Particles::ParticleIterator<dim> particle_two;
+  Tensor<1, 3>                     tangential_overlap;
+};
 
 template <int dim>
 class particle_wall_contact_info
@@ -39,13 +48,16 @@ class particle_wall_contact_info
    * boundary id. This is the commonly used constructor since it houses all the
    * information required to perform the contact calculation.
    *
-   * @param particle The iterator to the particle in contact with the wall
-   * @param normal_vector The outward pointing normal vector on the wall
-   * @param point_on_boundary A point that lies on the face
-   * @param boundary_id The boundary id. This id corresponds to the number attributed to the boundary condition.
+   * @param particle The iterator to the particle in contact with the wall.
+   * @param normal_vector The outward pointing normal vector on the wall.
+   * @param point_on_boundary A point that lies on the face.
+   * @param boundary_id The boundary id. This id corresponds to the number
+   * attributed to the boundary condition.
    *
+   * TODO: This should be a struct and normal_overlap, normal_relative_velocity
+   * and tangential_relative_velocity should be removed and be calculated on the
+   * fly as done for pp forces with particle_particle_contact_info
    */
-
   particle_wall_contact_info(const Particles::ParticleIterator<dim> &particle,
                              const Tensor<1, 3>       &normal_vector,
                              const Point<3>           &point_on_boundary,
@@ -89,4 +101,48 @@ class particle_wall_contact_info
   Tensor<1, 3>                     tangential_relative_velocity;
 };
 
+/**
+ * @brief Handle information related to the calculation of the particle-line
+ * contact forces.
+ */
+template <int dim>
+struct particle_line_contact_info
+{
+  Particles::ParticleIterator<dim> particle;
+  Point<3>                         point_one;
+  Point<3>                         point_two;
+};
+
+/**
+ * @brief Handle information related to the calculation of the particle-point
+ * contact forces.
+ */
+template <int dim>
+struct particle_point_contact_info
+{
+  Particles::ParticleIterator<dim> particle;
+  Point<3>                         point;
+};
+
+/**
+ * @brief Handle information related to the cell-line matching.
+ */
+template <int dim>
+struct cell_line_info
+{
+  typename Triangulation<dim>::active_cell_iterator cell;
+  Point<3>                                          point_one;
+  Point<3>                                          point_two;
+};
+
+/**
+ * @brief Handle information related to the cell-point matching.
+ */
+template <int dim>
+struct cell_point_info
+{
+  typename Triangulation<dim>::active_cell_iterator cell;
+  Point<3>                                          point;
+};
+
 #endif

include/dem/data_containers.h

@@ -18,9 +18,7 @@
 #define lethe_data_containers_h
 
 #include <dem/boundary_cells_info_struct.h>
-#include <dem/particle_particle_contact_info.h>
-#include <dem/particle_point_line_contact_info_struct.h>
-#include <dem/particle_wall_contact_info.h>
+#include <dem/contact_info.h>
 
 #include <deal.II/base/tensor.h>
 
@@ -121,21 +119,24 @@ namespace DEM
                                          Particles::ParticleIterator<dim>>
       particle_index_iterator_map;
 
-    // <particle id, point-line info>
+    // <particle id, line info>
     typedef std::unordered_map<types::particle_index,
-                               particle_point_line_contact_info_struct<dim>>
-      particle_point_line_contact_info;
+                               particle_line_contact_info<dim>>
+      particle_line_in_contact;
 
-    // <particle id, (particle iterator, point, point)>
-    typedef std::unordered_map<
-      types::particle_index,
-      std::tuple<Particles::ParticleIterator<dim>, Point<dim>, Point<dim>>>
+    // <particle id, point info>
+    typedef std::unordered_map<types::particle_index,
+                               particle_point_contact_info<dim>>
+      particle_point_in_contact;
+
+    // <particle id, line info>
+    typedef std::unordered_map<types::particle_index,
+                               particle_line_contact_info<dim>>
       particle_line_candidates;
 
     // <particle id, (particle iterator, point)>
-    typedef std::unordered_map<
-      types::particle_index,
-      std::pair<Particles::ParticleIterator<dim>, Point<dim>>>
+    typedef std::unordered_map<types::particle_index,
+                               particle_point_contact_info<dim>>
       particle_point_candidates;
 
     // <particle id, <global face id, particle iterator>>

include/dem/dem.h

@@ -376,11 +376,6 @@ class DEMSolver
    */
   std::shared_ptr<ParticlesForceChainsBase<dim>> particles_force_chains_object;
 
-  /**
-   * @brief The post-processing object.
-   */
-  LagrangianPostProcessing<dim> post_processing_object;
-
   /**
    * @brief The integrator object.
    */

include/dem/dem_contact_manager.h

@@ -279,10 +279,11 @@ class DEMContactManager
     particle_floating_wall_in_contact;
   typename dem_data_structures<dim>::particle_wall_in_contact
     particle_wall_in_contact;
-  typename dem_data_structures<dim>::particle_point_line_contact_info
-    particle_points_in_contact;
-  typename dem_data_structures<dim>::particle_point_line_contact_info
+  typename dem_data_structures<dim>::particle_line_in_contact
     particle_lines_in_contact;
+  typename dem_data_structures<dim>::particle_point_in_contact
+    particle_points_in_contact;
+
 
   // Container with all the contact information of adjacent
   // local/ghost-local for pairwise contact force calculation
@@ -299,20 +300,6 @@ class DEMContactManager
 
   // Containers with other information
   typename DEM::dem_data_structures<dim>::cell_vector periodic_cells_container;
-
-private:
-  // Broad search objects
-  ParticleParticleBroadSearch<dim>  particle_particle_broad_search_object;
-  ParticleWallBroadSearch<dim>      particle_wall_broad_search_object;
-  ParticlePointLineBroadSearch<dim> particle_point_line_broad_search_object;
-
-  // Fine search objects
-  ParticleParticleFineSearch<dim>  particle_particle_fine_search_object;
-  ParticleWallFineSearch<dim>      particle_wall_fine_search_object;
-  ParticlePointLineFineSearch<dim> particle_point_line_fine_search_object;
-
-  // Other relevant objects
-  FindCellNeighbors<dim> cell_neighbors_object;
 };
 
-#endif // lethe_dem_contact_manager_h
+#endif

include/dem/find_boundary_cells_information.h

@@ -18,6 +18,7 @@
 #define lethe_find_boundary_cells_information_h
 
 #include <dem/boundary_cells_info_struct.h>
+#include <dem/contact_info.h>
 #include <dem/data_containers.h>
 #include <dem/dem_solver_parameters.h>
 
@@ -87,19 +88,13 @@ class BoundaryCellsInformation
     return boundary_cells_information;
   }
 
-  std::unordered_map<
-    std::string,
-    std::pair<typename Triangulation<dim>::active_cell_iterator, Point<dim>>> &
+  std::unordered_map<std::string, cell_point_info<dim>> &
   get_boundary_cells_with_points()
   {
     return boundary_cells_with_points;
   }
 
-  std::unordered_map<
-    std::string,
-    std::tuple<typename Triangulation<dim>::active_cell_iterator,
-               Point<dim>,
-               Point<dim>>> &
+  std::unordered_map<std::string, cell_line_info<dim>> &
   get_boundary_cells_with_lines()
   {
     return boundary_cells_with_lines;
@@ -242,11 +237,7 @@ class BoundaryCellsInformation
     global_boundary_cells_information;
 
   // Structure that contains the boundary cells which have a line
-  std::unordered_map<
-    std::string,
-    std::tuple<typename Triangulation<dim>::active_cell_iterator,
-               Point<dim>,
-               Point<dim>>>
+  std::unordered_map<std::string, cell_line_info<dim>>
     boundary_cells_with_lines;
 
   // A vector of all the local cells with boundary lines. This vector is used in
@@ -255,9 +246,7 @@ class BoundaryCellsInformation
     local_cells_with_boundary_lines;
 
   // Structure that contains the boundary cells which have a point
-  std::unordered_map<
-    std::string,
-    std::pair<typename Triangulation<dim>::active_cell_iterator, Point<dim>>>
+  std::unordered_map<std::string, cell_point_info<dim>>
     boundary_cells_with_points;
 
   // Structure that contains the boundary cells with floating walls
@@ -286,4 +275,4 @@ class BoundaryCellsInformation
   bool display_pw_contact_expansion_warning = true;
 };
 
-#endif /* find_boundary_cells_information_h */
+#endif