EEntityDeleted and EComponentDeleted events published by World

include/Engine/Core/EComponentDeleted.h

@@ -0,0 +1,21 @@
+#ifndef EComponentDeleted_h__
+#define EComponentDeleted_h__
+
+#include "../Common.h"
+#include "Event.h"
+#include "Entity.h"
+
+namespace Events
+{
+
+struct ComponentDeleted : Event
+{
+    EntityID Entity;
+    std::string ComponentType;
+    // True if the component was deleted as a result of the entity it was attached to being deleted
+    bool Cascaded;
+};
+
+}
+
+#endif

include/Engine/Core/EEntityDeleted.h

@@ -0,0 +1,19 @@
+#ifndef EEntityDeleted_h__
+#define EEntityDeleted_h__
+
+#include "Event.h"
+#include "Entity.h"
+
+namespace Events
+{
+
+struct EntityDeleted : Event
+{
+    EntityID DeletedEntity;
+    // True if the entity deletion was triggered because the entity's parent was deleted before it
+    bool Cascaded;
+};
+
+}
+
+#endif

include/Engine/Core/World.h

@@ -5,11 +5,15 @@
 #include "Entity.h"
 #include "ObjectPool.h"
 #include "ComponentPool.h"
+#include "EventBroker.h"
 
 class World
 {
 public:
     World() = default;
+    World(EventBroker* eventBroker) 
+        : m_EventBroker(eventBroker)
+    { }
     ~World();
 
     // Create empty entity
@@ -46,6 +50,7 @@ public:
     std::string GetName(EntityID entity) const;
 
 private:
+    EventBroker* m_EventBroker = nullptr;
     EntityID m_CurrentEntityID = 0;
 
     std::unordered_map<EntityID, EntityID> m_EntityParents;
@@ -55,6 +60,7 @@ private:
     std::unordered_map<EntityID, std::string> m_EntityNames;
 
     EntityID generateEntityID();
+    void deleteEntityRecursive(EntityID entity, bool cascaded = false);
 };
 
 #endif

src/Engine/Core/World.cpp

@@ -1,4 +1,6 @@
 #include "Core/World.h"
+#include "Core/EEntityDeleted.h"
+#include "Core/EComponentDeleted.h"
 
 World::~World()
 {
@@ -21,37 +23,7 @@ EntityID World::CreateEntity(EntityID parent /*= 0*/)
 
 void World::DeleteEntity(EntityID entity)
 {
-    // Delete components
-    for (auto& pair : m_ComponentPools) {
-        auto& pool = pair.second;
-        if (pool->KnowsEntity(entity)) {
-            auto& c = pool->GetByEntity(entity);
-            pool->Delete(c);
-        }
-    }
-
-    // Loop through children
-    std::vector<EntityID> childrenToDelete;
-    auto children = m_EntityChildren.equal_range(entity);
-    for (auto it = children.first; it != children.second; ++it) {
-        childrenToDelete.push_back(it->second);
-    }
-    for (auto& child : childrenToDelete) {
-        DeleteEntity(child);
-    }
-
-    EntityID parent = m_EntityParents.at(entity);
-    m_EntityParents.erase(entity);
-    auto parentChildren = m_EntityChildren.equal_range(parent);
-    for (auto it = parentChildren.first; it != parentChildren.second; ++it) {
-        if (it->second == entity) {
-            m_EntityChildren.erase(it);
-            break;
-        }
-    }
-
-    // Erase potential name
-    m_EntityNames.erase(entity);
+    deleteEntityRecursive(entity, false);
 }
 
 bool World::ValidEntity(EntityID entity) const
@@ -96,7 +68,15 @@ void World::DeleteComponent(EntityID entity, const std::string& componentType)
 {
     ComponentPool* pool = m_ComponentPools.at(componentType);
     ComponentWrapper c = pool->GetByEntity(entity);
-    return pool->Delete(c);
+    pool->Delete(c);
+
+    if (m_EventBroker != nullptr) {
+        Events::ComponentDeleted e;
+        e.Entity = entity;
+        e.ComponentType = componentType;
+        e.Cascaded = false;
+        m_EventBroker->Publish(e);
+    }
 }
 
 const ComponentPool* World::GetComponents(const std::string& componentType)
@@ -155,3 +135,52 @@ EntityID World::generateEntityID()
     return m_CurrentEntityID++;
 }
 
+void World::deleteEntityRecursive(EntityID entity, bool cascaded /*= false*/)
+{
+    if (m_EventBroker != nullptr) {
+        Events::EntityDeleted e;
+        e.DeletedEntity = entity;
+        e.Cascaded = cascaded;
+        m_EventBroker->Publish(e);
+    }
+
+    // Delete components
+    for (auto& pair : m_ComponentPools) {
+        auto& pool = pair.second;
+        if (pool->KnowsEntity(entity)) {
+            auto& c = pool->GetByEntity(entity);
+            pool->Delete(c);
+            if (m_EventBroker != nullptr) {
+                Events::ComponentDeleted e;
+                e.Entity = entity;
+                e.ComponentType = pair.first;
+                e.Cascaded = true;
+                m_EventBroker->Publish(e);
+            }
+        }
+    }
+
+    // Loop through children
+    std::vector<EntityID> childrenToDelete;
+    auto children = m_EntityChildren.equal_range(entity);
+    for (auto it = children.first; it != children.second; ++it) {
+        childrenToDelete.push_back(it->second);
+    }
+    for (auto& child : childrenToDelete) {
+        deleteEntityRecursive(child, true);
+    }
+
+    EntityID parent = m_EntityParents.at(entity);
+    m_EntityParents.erase(entity);
+    auto parentChildren = m_EntityChildren.equal_range(parent);
+    for (auto it = parentChildren.first; it != parentChildren.second; ++it) {
+        if (it->second == entity) {
+            m_EntityChildren.erase(it);
+            break;
+        }
+    }
+
+    // Erase potential name
+    m_EntityNames.erase(entity);
+}
+

src/Game/Game.cpp

@@ -57,7 +57,7 @@ Game::Game(int argc, char* argv[])
     m_FrameStack->Height = m_Renderer->Resolution().Height;
 
     // Create a world
-    m_World = new World();
+    m_World = new World(m_EventBroker);
     std::string mapToLoad = m_Config->Get<std::string>("Debug.LoadMap", "");
     if (!mapToLoad.empty()) {
         auto file = ResourceManager::Load<EntityFile>(mapToLoad);