code.delx.au - gnu-emacs/blob - test/manual/etags/cp-src/clheir.hpp

   1 /* ======================================================================= */
   2 /*                                 CLHEIR.H                                */
   3 /* ======================================================================= */
   4
   5 // CLASS HEIRARCHY
   6 // Locations or Agents are both of type generic_object. Generic_objects may
   7 // have states, and are responsible for updating their states appropriately
   8 // when their step() functions are executed.
   9
  10 extern void init_registry(void);
  11 extern void step_everybody(void);
  12
  13 class generic_object
  14     {
  15     int where_in_registry;
  16 public:
  17     generic_object();  // enter generic_object into ObjectRegistry
  18     // We never copy generic_objects, so we don't need a copy constructor.
  19     ~generic_object(void);  // delete from ObjectRegistry
  20     // Simulation steps, accommodate different kinds of time
  21     virtual void compute_next_state(void) { }
  22     virtual void step(void) { }
  23     };
  24
  25 // =======================================================================
  26
  27 // Locations can be regular (like a field of squares or hexagons) or
  28 // irregular. Regular locations have 2-D or 3-D positions represented
  29 // by integers. Locations are never copied; no need for copy constructors.
  30
  31 const int max_num_directions = 6; // handles both cubes and hexagons
  32
  33 class location: public generic_object
  34     {
  35     // Any kind of location needs a physical position, but for a regular
  36     // location, this may be implicit, and for an irregular location, it
  37     // should be custom-defined.
  38
  39     // Any kind of location needs a private list of neighbors, but for a
  40     // regular location, this may be implicit.
  41
  42 public:
  43     location() { }
  44     ~location();
  45     };
  46
  47 class irregular_location: public location
  48     {
  49     double x, y, z;
  50 public:
  51     irregular_location(double xi, double yi, double zi)
  52         { x = xi; y = yi; z = zi; }
  53     ~irregular_location();
  54     };
  55
  56 class discrete_location: public location
  57     {
  58     int x, y, z;
  59     class location *neighbors[max_num_directions];
  60     void clear_neighbors(void);
  61 public:
  62     discrete_location(int xi, int yi, int zi):
  63         x(xi), y(yi), z(zi)
  64             { clear_neighbors(); }
  65     ~discrete_location(void);
  66     void assign_neighbor(int direction, location *x)
  67         { neighbors[direction] = x; }
  68     };
  69
  70 // =======================================================================
  71
  72 // Agents are generic_objects with locations, who can move. Examples in
  73 // Pacman would be the protagonist, the monsters, and the monsters' ghosts.
  74
  75 class agent: public generic_object
  76     {
  77     location *where;
  78 public:
  79     agent();
  80     ~agent();
  81     void move(int);
  82     };