Add Space class

The Space class handles the simulation space

src/md/System.hpp

@@ -15,9 +15,7 @@
 #include <vector>
 
 #include "Atom.hpp"
-
-typedef std::function<double(double)> PotentialFunction;
-typedef std::function<double(double)> ForceFunction;
+#include "Potentials.hpp"
 
 class System {
 private:
@@ -28,8 +26,7 @@ private:
   std::vector<double> forceTableOld;  ///< Force table in the previous step
   std::vector<double> potentialTable; ///< Potential table
 
-  ForceFunction     forceGenerator;     ///< Force generator
-  PotentialFunction potentialGenerator; ///< Potential generator
+  Potential *potential; ///< Potential function
 
   double rcut;  ///< Cutoff radius
   double rcut2; ///< Cutoff radius squared
@@ -38,6 +35,8 @@ private:
 
   double timeDelta = 0; ///< Time delta between steps
 
+  double lx, ly, lz; ///< Box size, if periodic boundary conditions are used
+
   /**
    * @brief Initialize the force and potential tables
    *
@@ -50,12 +49,18 @@ private:
    */
   void evaulateForces();
 
+  /**
+   * @brief Build the grid based on the cutoff radius.
+   *
+   * This function partitions the space into cells of size rcut x rcut x rcut.
+   */
+  void buildGrid();
+
 public:
-  explicit System(double            timeDelta,
-                  double            rcut,
-                  PotentialFunction potentialFunction,
-                  ForceFunction     forceFunction,
-                  std::size_t       tableResolution = 1000);
+  explicit System(double      timeDelta,
+                  double      rcut,
+                  Potential  *potential,
+                  std::size_t tableResolution = 1000);
 
   void step();
 
@@ -84,4 +89,13 @@ public:
    *
    */
   void printAtoms();
+
+  /**
+   * @brief Set the simulation box size
+   *
+   * @param lx
+   * @param ly
+   * @param lz
+   */
+  void setBoxSize(double lx, double ly, double lz);
 };