source/game/stage.h

   1 #ifndef MSP_GAME_STAGE_H_
   2 #define MSP_GAME_STAGE_H_
   3
   4 #include <memory>
   5 #include <msp/datafile/collection.h>
   6 #include <msp/time/timedelta.h>
   7 #include "eventbus.h"
   8 #include "events.h"
   9 #include "eventsource.h"
  10 #include "handle.h"
  11
  12 namespace Msp::Game {
  13
  14 class Camera;
  15 class Root;
  16 class System;
  17
  18 class Stage
  19 {
  20 public:
  21         using EventSource = Game::EventSource<Events::EntityCreated, Events::EntityDestroyed,
  22                 Events::ComponentCreated, Events::ComponentDestroyed, Events::CameraChanged>;
  23
  24 private:
  25         DataFile::Collection &resources;
  26         PoolPool pools;
  27         EventBus event_bus;
  28         EventSource event_source;
  29         EventObserver event_observer;
  30         /* Use unique_ptr because there's only one root per stage so it's pointless
  31         to put it in a pool. */
  32         std::unique_ptr<Root> root;
  33         std::vector<std::unique_ptr<System>> systems;
  34         Handle<Camera> active_camera;
  35
  36 public:
  37         Stage(DataFile::Collection &);
  38         ~Stage();
  39
  40         DataFile::Collection &get_resources() const { return resources; }
  41         PoolPool &get_pools() { return pools; }
  42         EventBus &get_event_bus() { return event_bus; }
  43         EventSource &get_event_source() { return event_source; }
  44         Handle<Root> get_root() { return Handle<Root>::from_object(root.get()); }
  45
  46         template<typename T, typename F>
  47         void iterate_objects(const F &);
  48
  49         template<typename T, typename... Args>
  50         T &add_system(Args &&...);
  51
  52         void remove_system(System &);
  53         const std::vector<std::unique_ptr<System>> &get_systems() const { return systems; }
  54
  55         template<typename T>
  56         T *get_system() const;
  57
  58         void set_active_camera(Handle<Camera>);
  59         Handle<Camera> get_active_camera() const { return active_camera; }
  60
  61         void synthesize_initial_events(EventObserver &);
  62 private:
  63         void synthesize_initial_events(Handle<Entity>, EventObserver &);
  64
  65 public:
  66         void tick(Time::TimeDelta);
  67 };
  68
  69 template<typename T, typename F>
  70 inline void Stage::iterate_objects(const F &func)
  71 {
  72         pools.get_pool<T>().iterate_objects(func);
  73 }
  74
  75 template<typename T, typename... Args>
  76 inline T &Stage::add_system(Args &&... args)
  77 {
  78         systems.emplace_back(std::make_unique<T>(*this, std::forward<Args>(args)...));
  79         return static_cast<T &>(*systems.back());
  80 }
  81
  82 template<typename T>
  83 inline T *Stage::get_system() const
  84 {
  85         for(const auto &s: systems)
  86                 if(T *ts = dynamic_cast<T *>(s.get()))
  87                         return ts;
  88         return nullptr;
  89 }
  90
  91 } // namespace Msp::Game
  92
  93 #endif