Add Scene with systems

- Add Scene class which populates the engine with Systems which handles
  all logic in the game
- Add Systems to ecs

CopiumEngine/src/copium/ecs/ECSManager.cpp

@@ -4,6 +4,10 @@
 
 namespace Copium
 {
+  ECSManager::ECSManager()
+    : systemPool{std::make_unique<SystemPool>(this)}
+  {}
+
   ECSManager::~ECSManager()
   {
     for (auto&& components : componentPool)
@@ -13,6 +17,11 @@ namespace Copium
     componentPool.clear();
   }
 
+  void ECSManager::UpdateSystems()
+  {
+    systemPool->Update();
+  }
+
   size_t ECSManager::GetEntityCount() const
   {
     return entities.size();

CopiumEngine/src/copium/ecs/ECSManager.h

@@ -3,6 +3,7 @@
 
 #include "copium/ecs/ComponentPool.h"
 #include "copium/ecs/Config.h"
+#include "copium/ecs/SystemPool.h"
 #include "copium/util/Common.h"
 
 #include <functional>
@@ -18,10 +19,21 @@ namespace Copium
   private:
     std::unordered_set<EntityID> entities;
     std::map<std::type_index, ComponentPoolBase*> componentPool;
+
+    std::unique_ptr<SystemPool> systemPool;
     int currentEntityId = 1;
   public:
+    ECSManager();
     ~ECSManager();
 
+    template <typename SystemClass, typename... Args>
+    SystemOrderer AddSystem(const Args&... args)
+    {
+      return systemPool->AddSystem(typeid(SystemClass), new SystemClass{args...});
+    }
+
+    void UpdateSystems();
+
     EntityID CreateEntity();
     void DestroyEntity(EntityID entity);
     size_t GetEntityCount() const;
@@ -37,7 +49,7 @@ namespace Copium
     template <typename Component, typename... Args>
     Component& AddComponent(EntityID entity, Args&&... args)
     {
-      return AddComponent(entity, Component(args...));
+      return AddComponent(entity, Component{args...});
     }
 
     template <typename Component>
@@ -76,7 +88,7 @@ namespace Copium
     {
       auto pool = GetComponentPoolAssure<Component>();
       Component* component = pool->FindComponent(entity);
-      ASSERT(component, "Entity did not contain component (entity=%u, Component=%s)", entity, typeid(Component).name());
+      CP_ASSERT(component, "Entity did not contain component (entity=%u, Component=%s)", entity, typeid(Component).name());
       return *component;
     }
 

CopiumEngine/src/copium/ecs/System.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include "copium/ecs/ECSManager.h"
+#include "copium/ecs/SystemBase.h"
+#include "copium/ecs/Entity.h"
+
+namespace Copium
+{
+  template <typename... Components>
+  class System : public SystemBase
+  {
+  public:
+    void Run() override
+    {
+      manager->Each<Components...>([&](EntityID entityId, Components&... components) { RunEntity(Entity{manager, entityId}, components...); });
+    }
+
+    virtual void RunEntity(Entity entity, Components&... components) = 0;
+  };
+}

CopiumEngine/src/copium/ecs/SystemBase.h

@@ -0,0 +1,16 @@
+#pragma once
+
+namespace Copium
+{
+  class ECSManager;
+
+  class SystemBase
+  {
+    friend class SystemPool;
+  protected:
+    ECSManager* manager;
+
+  public:
+    virtual void Run() = 0;
+  };
+}

CopiumEngine/src/copium/ecs/SystemOrderer.cpp

@@ -0,0 +1,21 @@
+#include "copium/ecs/SystemOrderer.h"
+
+#include "copium/ecs/SystemPool.h"
+
+namespace Copium
+{
+  SystemOrderer::SystemOrderer(std::type_index systemId, SystemPool* systemPool)
+    : systemId{systemId},
+      systemPool{systemPool}
+  {}
+
+  void SystemOrderer::Before(const std::type_index& otherSystemId)
+  {
+    systemPool->MoveSystemBefore(systemId, otherSystemId);
+  }
+
+  void SystemOrderer::After(const std::type_index& otherSystemId)
+  {
+    systemPool->MoveSystemAfter(systemId, otherSystemId);
+  }
+}

CopiumEngine/src/copium/ecs/SystemOrderer.h

@@ -0,0 +1,35 @@
+#pragma once
+
+#include <vector>
+#include <map>
+#include <typeindex>
+
+namespace Copium
+{
+  class SystemPool;
+
+  class SystemOrderer
+  {
+  private:
+    std::type_index systemId;
+    SystemPool* systemPool = nullptr;
+  public:
+    SystemOrderer(std::type_index systemId, SystemPool* systemPool);
+
+    template <typename Other>
+    void Before()
+    {
+      Before(typeid(Other));
+    }
+
+    template <typename Other>
+    void After()
+    {
+      After(typeid(Other));
+    }
+
+  private:
+    void Before(const std::type_index& otherSystemId);
+    void After(const std::type_index& otherSystemId);
+  };
+}

CopiumEngine/src/copium/ecs/SystemPool.cpp

@@ -0,0 +1,59 @@
+#include "copium/ecs/SystemPool.h"
+
+namespace Copium
+{
+  SystemPool::SystemPool(ECSManager* manager)
+    : manager{manager}
+  {}
+
+  SystemPool::~SystemPool()
+  {
+    for (auto& system : systemOrder)
+    {
+      delete system;
+    }
+    systemOrder.clear();
+    systems.clear();
+  }
+
+  SystemOrderer SystemPool::AddSystem(const std::type_index& systemId, SystemBase* system)
+  {
+    system->manager = manager;
+    systems.emplace(systemId, system);
+    systemOrder.emplace_back(system);
+    return SystemOrderer{systemId, this};
+  }
+
+  void SystemPool::Update()
+  {
+    for (auto& system : systemOrder)
+    {
+      system->Run();
+    }
+  }
+
+  void SystemPool::MoveSystemAfter(const std::type_index& systemId, const std::type_index& afterSystemId)
+  {
+    auto it1 = systems.find(systemId);
+    CP_ASSERT(it1 != systems.end(), "System does not exist in SystemPool");
+    auto it2 = systems.find(afterSystemId);
+    CP_ASSERT(it2 != systems.end(), "System does not exist in SystemPool");
+
+    auto itSystemId = std::find(systemOrder.rbegin(), systemOrder.rend(), it1->second);
+    auto itAfterSystemId = std::find(systemOrder.rbegin(), systemOrder.rend(), it2->second);
+    std::rotate(itSystemId, itSystemId + 1, itAfterSystemId);
+  }
+
+  void SystemPool::MoveSystemBefore(const std::type_index& systemId, const std::type_index& beforeSystemId)
+  {
+    auto it1 = systems.find(systemId);
+    CP_ASSERT(it1 != systems.end(), "System does not exist in SystemPool");
+    auto it2 = systems.find(beforeSystemId);
+    CP_ASSERT(it2 != systems.end(), "System does not exist in SystemPool");
+
+    auto itSystemId = std::find(systemOrder.rbegin(), systemOrder.rend(), it1->second);
+    auto itBeforeSystemId = std::find(systemOrder.rbegin(), systemOrder.rend(), it2->second);
+
+    std::rotate(itSystemId, itSystemId + 1, itBeforeSystemId + 1);
+  }
+}

CopiumEngine/src/copium/ecs/SystemPool.h

@@ -0,0 +1,32 @@
+#pragma once
+
+#include "copium/ecs/SystemBase.h"
+#include "copium/ecs/SystemOrderer.h"
+#include "copium/util/Common.h"
+
+#include <vector>
+#include <map>
+#include <typeindex>
+
+namespace Copium
+{
+  class ECSManager;
+
+  class SystemPool final
+  {
+    CP_DELETE_COPY_AND_MOVE_CTOR(SystemPool);
+  private:
+    ECSManager* manager;
+    std::map<std::type_index, SystemBase*> systems;
+    std::vector<SystemBase*> systemOrder;
+
+  public:
+    SystemPool(ECSManager* manager);
+    ~SystemPool();
+    SystemOrderer AddSystem(const std::type_index& systemId, SystemBase* system);
+    void Update();
+
+    void MoveSystemAfter(const std::type_index& systemId, const std::type_index& afterSystemId);
+    void MoveSystemBefore(const std::type_index& systemId, const std::type_index& beforeSystemId);
+  };
+}