Basic and working entity system with a really ugly test case

src/Engine/Core/ComponentPool.cpp

@@ -0,0 +1,79 @@
+#include "Core/ComponentPool.h"
+
+
+
+ComponentWrapper ComponentPoolForwardIterator::operator*() const
+{
+    char* data = &(*m_MemoryPoolIterator);
+    ComponentWrapper wrapper(m_ComponentInfo, data);
+    return wrapper;
+}
+
+bool ComponentPoolForwardIterator::operator==(const ComponentPoolForwardIterator& other) const
+{
+    return m_MemoryPoolIterator == other.m_MemoryPoolIterator;
+}
+
+bool ComponentPoolForwardIterator::operator!=(const ComponentPoolForwardIterator& other) const
+{
+    return m_MemoryPoolIterator != other.m_MemoryPoolIterator;
+}
+
+ComponentPoolForwardIterator& ComponentPoolForwardIterator::operator++(int)
+{
+    ComponentPoolForwardIterator copyIter(*this);
+    operator++();
+    return copyIter;
+}
+
+ComponentPoolForwardIterator& ComponentPoolForwardIterator::operator++()
+{
+    ++m_MemoryPoolIterator;
+    return *this;
+}
+
+//const ::ComponentInfo& ComponentPool::ComponentInfo() const
+//{
+//    return m_ComponentInfo;
+//}
+
+ComponentWrapper ComponentPool::Allocate(EntityID entity)
+{
+    char* data = m_Pool.Allocate();
+    memcpy(data, &entity, sizeof(EntityID));
+    m_EntityToComponent[entity] = data;
+    return ComponentWrapper(m_ComponentInfo, data);
+}
+
+ComponentWrapper ComponentPool::GetByEntity(EntityID ent)
+{
+    return ComponentWrapper(m_ComponentInfo, m_EntityToComponent.at(ent));
+}
+
+void ComponentPool::Delete(ComponentWrapper& wrapper)
+{
+    m_EntityToComponent.erase(wrapper.EntityID);
+    m_Pool.Free(wrapper.Data);
+}
+
+ComponentPool::iterator ComponentPool::begin() const
+{
+    return iterator(m_ComponentInfo, m_Pool.begin(), m_Pool.end());
+}
+
+ComponentPool::iterator ComponentPool::end() const
+{
+    return iterator(m_ComponentInfo, m_Pool.end(), m_Pool.end());
+}
+
+template <typename InterpretType /*= char*/>
+void ComponentPool::Dump() const
+{
+    m_Pool.Dump<InterpretType>();
+}
+
+template <typename InterpretType /*= char*/, typename OutStream>
+void ComponentPool::Dump(OutStream& out) const
+{
+    m_Pool.Dump<InterpretType>(out);
+}

src/Engine/Core/World.cpp

@@ -0,0 +1,54 @@
+#include "Core/World.h"
+
+World::~World()
+{
+    for (auto& pool : m_ComponentPools) {
+        delete pool.second;
+    }
+}
+
+EntityID World::CreateEntity(EntityID parent /*= 0*/)
+{
+    EntityID newEntity = generateEntityID();
+    m_EntityParents[newEntity] = parent;
+    if (parent != 0) {
+        m_EntityChildren.insert(std::make_pair(parent, newEntity));
+    }
+    return newEntity;
+}
+
+void World::RegisterComponent(ComponentInfo& ci)
+{
+    m_ComponentPools[ci.Name] = new ComponentPool(ci);
+}
+
+ComponentWrapper World::AttachComponent(EntityID entity, std::string componentType)
+{
+    ComponentPool* pool = m_ComponentPools.at(componentType);
+    const ComponentInfo& ci = pool->ComponentInfo();
+
+    // Allocate space for the component
+    ComponentWrapper c = pool->Allocate(entity);
+    // Write default values
+    memcpy(c.Data, ci.Defaults.get(), ci.Meta.Stride);
+
+    return c;
+}
+
+ComponentWrapper World::GetComponent(EntityID entity, std::string componentType)
+{
+    ComponentPool* pool = m_ComponentPools.at(componentType);
+    return pool->GetByEntity(entity);
+}
+
+const ComponentPool& World::GetComponents(std::string componentType)
+{
+    return *m_ComponentPools.at(componentType);
+}
+
+EntityID World::generateEntityID()
+{
+    // TODO: Make EntityID generation smarter
+    return m_CurrentEntityID++;
+}
+