Merge remote-tracking branch 'origin/master' into Rendering

# Conflicts:
#	include/Engine/Editor/EditorSystem.h
#	include/Engine/Rendering/EPicking.h
#	include/Engine/Rendering/Renderer.h
#	include/Game/Game.h
#	resources/Schema/Components.xsd
#	resources/Schema/Entities/Test.xml
#	src/Engine/Editor/EditorSystem.cpp
#	src/Engine/Rendering/RawModel.cpp
#	src/Engine/Rendering/RenderQueueFactory.cpp
#	src/Engine/Rendering/Renderer.cpp
#	src/Game/Game.cpp

include/Engine/Collision/Collision.h

@@ -0,0 +1,59 @@
+#ifndef Collision_h__
+#define Collision_h__
+
+//NOTE: Collision.h needs to be #included before <GLFW/glfw3.h>, 
+//because Collision #includes "RawModel.h", which has "Texture.h", which has "OpenGL.h" which must be #included first
+//or you will get "fatal error C1189: #error:  gl.h included before glew.h"
+
+#include <vector>
+
+#include "Core/Ray.h"
+#include "Core/AABB.h"
+#include "Engine/Rendering/RawModel.h"
+#include "Core/Entity.h"
+
+class World;
+struct ComponentWrapper;
+
+namespace Collision
+{
+//Return true if the ray hits the box.
+bool RayAABBIntr(const Ray& ray, const AABB& box);
+bool RayVsAABB(const Ray& ray, const AABB& box);
+//Return true if the ray hits the box, also outputs distance from ray origin to intersection point in [outDistance].
+bool RayVsAABB(const Ray& ray, const AABB& box, float& outDistance);
+
+//Return true if the ray hits any of the triangles in the model. Stops checking when a hit is detected.
+bool RayVsModel(const Ray& ray, 
+    const std::vector<RawModel::Vertex>& modelVertices,
+    const std::vector<unsigned int>& modelIndices);
+//Return true if the ray hits any of the triangles in the model.
+//Also returns the position of the intersection point. Will loop through all the whole model indices.
+bool RayVsModel(const Ray& ray,
+    const std::vector<RawModel::Vertex>& modelVertices,
+    const std::vector<unsigned int>& modelIndices,
+    glm::vec3& outHitPosition);
+//Return true if the ray hits any of the triangles in the model.
+//Also returns the distance from the ray origin to the closest 
+//intersection point, and the barycentric u,v-coordinates. Will loop through all the whole model indices.
+bool RayVsModel(const Ray& ray,
+    const std::vector<RawModel::Vertex>& modelVertices,
+    const std::vector<unsigned int>& modelIndices,
+    float& outDistance,
+    float& outUCoord,
+    float& outVCoord);
+
+//Return true if the boxes are intersecting.
+bool AABBVsAABB(const AABB& a, const AABB& b);
+//Return true if the boxes are intersecting.
+//Also outputs the minimum translation that box [a] would need in order to resolve collision.
+bool AABBVsAABB(const AABB& a, const AABB& b, glm::vec3& minimumTranslation);
+bool IsSameBoxProbably(const AABB& first, const AABB& second, const float epsilon = 0.0001f);
+
+//Returns true if the entity has a boundingbox. Outputs the aabb in [outBox].
+bool GetEntityBox(World* world, EntityID entity, AABB& outBox, bool forceBoxFromModel = false);
+bool GetEntityBox(World* world, ComponentWrapper& AABBComponent, AABB& outBox);
+
+}
+
+#endif

include/Engine/Collision/CollisionSystem.h

@@ -0,0 +1,31 @@
+#ifndef CollisionSystem_h__
+#define CollisionSystem_h__
+
+#include <GLFW/glfw3.h>
+#include <glm/common.hpp>
+
+#include "Common.h"
+#include "Core/System.h"
+#include "Core/EventBroker.h"
+#include "Core/EKeyUp.h"
+
+class CollisionSystem : public PureSystem
+{
+public:
+    CollisionSystem(EventBroker* eventBroker)
+        : PureSystem(eventBroker, "AABB")
+        , zPress(false)
+    {
+        //TODO: Debug stuff, remove later.
+        EVENT_SUBSCRIBE_MEMBER(m_EKeyUp, &CollisionSystem::OnKeyUp);
+    }
+
+    virtual void UpdateComponent(World* world, ComponentWrapper& cAABB, double dt) override;
+
+private:
+    bool zPress;
+    EventRelay<CollisionSystem, Events::KeyUp> m_EKeyUp;
+    bool OnKeyUp(const Events::KeyUp &event);
+};
+
+#endif

include/Engine/Collision/ETrigger.h

@@ -0,0 +1,39 @@
+#ifndef Events_TriggerEnter_h__
+#define Events_TriggerEnter_h__
+
+#include "../Core/EventBroker.h"
+#include "../Core/Entity.h"
+
+namespace Events
+{
+
+/** Thrown once, when an entity is only touching a trigger. */
+struct TriggerTouch : Event
+{
+    /** The id of the entity that touches the trigger. */
+    EntityID Entity;
+    /** The id of the trigger entity. */
+    EntityID Trigger;
+};
+
+/** Thrown once, when an entity has completely left a trigger. */
+struct TriggerLeave : Event
+{
+    /** The id of the entity that left the trigger. */
+    EntityID Entity;
+    /** The id of the trigger entity. */
+    EntityID Trigger;
+};
+
+/** Thrown once, when an entity is completely contained inside a trigger. */
+struct TriggerEnter : Event
+{
+    /** The id of the entity that entered the trigger. */
+    EntityID Entity;
+    /** The id of the trigger entity. */
+    EntityID Trigger;
+};
+
+}
+
+#endif

include/Engine/Collision/TriggerSystem.h

@@ -0,0 +1,38 @@
+#ifndef TriggerSystem_h__
+#define TriggerSystem_h__
+
+#include <glm/common.hpp>
+#include <unordered_set>
+
+#include "Core/System.h"
+#include "Core/EventBroker.h"
+#include "ETrigger.h"
+
+class AABB;
+
+class TriggerSystem : public PureSystem
+{
+public:
+    TriggerSystem(EventBroker* eventBroker)
+        : PureSystem(eventBroker, "Trigger")
+    {}
+
+    virtual void UpdateComponent(World* world, ComponentWrapper& collision, double dt) override;
+
+private:
+    std::unordered_map<EntityID, std::unordered_set<EntityID>> m_EntitiesTouchingTrigger;
+    std::unordered_map<EntityID, std::unordered_set<EntityID>> m_EntitiesCompletelyInTrigger;
+
+    //True if leave event was thrown.
+    bool throwLeaveIfWasInTrigger(std::unordered_set<EntityID>& triggerSet, EntityID pId, EntityID tId);
+    template<typename Event>
+    void publish(EntityID pId, EntityID tId)
+    {
+        Event e;
+        e.Trigger = tId;
+        e.Entity = pId;
+        m_EventBroker->Publish(e);
+    }
+};
+
+#endif

include/Engine/Common.h

@@ -4,4 +4,5 @@
 #include <map>
 #include <unordered_map>
 
-#include "Core/Util/Logging.h"
+#include "Core/Util/Logging.h"
+#include "Core/Util/IfDebug.h"

include/Engine/Core/AABB.h

@@ -0,0 +1,29 @@
+#ifndef AABB_h__
+#define AABB_h__
+
+#include "../GLM.h"
+
+class AABB
+{
+public:
+    AABB() = default;
+    //No checks are made. Values in minPos must be less than values in maxPos, i.e. min.x < max.x, etc.
+    AABB(const glm::vec3& minPos, const glm::vec3& maxPos);
+    AABB(const glm::vec4& minPos, const glm::vec4& maxPos);
+    //No checks are made. Size must consist of non-negative numbers.
+    virtual void CreateFromCenter(const glm::vec3& center, const glm::vec3& size);
+    virtual ~AABB();
+
+    const glm::vec3& MinCorner() const { return m_MinCorner; }
+    const glm::vec3& MaxCorner() const { return m_MaxCorner; }
+    const glm::vec3& Center() const { return m_Center; }
+    const glm::vec3 Size() const { return 2.0f * m_HalfSize; }
+    const glm::vec3& HalfSize() const { return m_HalfSize; }
+private:
+    glm::vec3 m_MinCorner;
+    glm::vec3 m_MaxCorner;
+    glm::vec3 m_Center;
+    glm::vec3 m_HalfSize;
+};
+
+#endif

include/Engine/Core/ComponentInfo.h

@@ -12,9 +12,16 @@ struct ComponentInfo
         unsigned int Stride = 0;
 	};
 
+    struct Field_t
+    {
+        std::string Type;
+        unsigned int Offset;
+        unsigned int Stride;
+    };
+
 	std::string Name;
-	std::unordered_map<std::string, std::string> FieldTypes;
-	std::unordered_map<std::string, unsigned int> FieldOffsets;
+    std::unordered_map<std::string, Field_t> Fields;
+    std::vector<const Field_t*> FieldsInOrder;
 	Meta_t Meta;
     std::shared_ptr<char> Defaults = nullptr;
 };

include/Engine/Core/ComponentPool.h

@@ -20,7 +20,7 @@ public:
 	~ComponentPoolForwardIterator() = default;
 	ComponentPoolForwardIterator& operator=(const ComponentPoolForwardIterator& other) = default;
 	ComponentPoolForwardIterator& operator++();
-	ComponentPoolForwardIterator& operator++(int);
+	ComponentPoolForwardIterator operator++(int);
 	bool operator!=(const ComponentPoolForwardIterator& other) const;
 	bool operator==(const ComponentPoolForwardIterator& other) const;
 	ComponentWrapper operator*() const;

include/Engine/Core/ComponentWrapper.h

@@ -21,7 +21,7 @@ struct ComponentWrapper
     template <typename T>
     T& Property(std::string name)
     {
-        unsigned int offset = Info.FieldOffsets.at(name);
+        unsigned int offset = Info.Fields.at(name).Offset;
         return *reinterpret_cast<T*>(&Data[offset]);
     }
 
@@ -78,8 +78,9 @@ public:
     void AddProperty(std::string fieldName, T defaultValue)
     {
         m_DefaultValues.push_back(defaultValue);
-        m_ComponentInfo.FieldTypes[fieldName] = typeid(T).name();
-        m_ComponentInfo.FieldOffsets[fieldName] = m_ComponentInfo.Meta.Stride;
+        m_ComponentInfo.Fields[fieldName].Name = typeid(T).name();
+        m_ComponentInfo.Fields[fieldName].Offset = m_ComponentInfo.Meta.Stride;
+        m_ComponentInfo.Fields[fieldName].Stride = sizeof(T);
         m_ComponentInfo.Meta.Stride += sizeof(T);
     }
     

include/Engine/Core/EFileDropped.h

@@ -0,0 +1,16 @@
+#ifndef EFileDropped_h__
+#define EFileDropped_h__
+
+#include "EventBroker.h"
+
+namespace Events
+{
+
+struct FileDropped : Event
+{
+    std::string Path;
+};
+
+}
+
+#endif

include/Engine/Core/EPlayerDamage.h

@@ -0,0 +1,20 @@
+#ifndef EPlayerDamage_h__
+#define EPlayerDamage_h__
+
+#include "EventBroker.h"
+#include "../Core/Entity.h"
+
+namespace Events
+{
+
+struct PlayerDamage : Event
+{
+    double DamageAmount;
+    EntityID PlayerDamagedID;
+    //optional TypeOfDamage
+    std::string TypeOfDamage;
+};
+
+}
+
+#endif

include/Engine/Core/EPlayerDeath.h

@@ -0,0 +1,20 @@
+#ifndef EPlayerDeath_h__
+#define EPlayerDeath_h__
+
+#include "EventBroker.h"
+#include "../Core/Entity.h"
+
+namespace Events
+{
+
+struct PlayerDeath : Event
+{
+    //KilledBy,KilledByWhat is optional for now. It might be used later in the playerlog-system
+    EntityID KilledBy;
+    EntityID PlayerID;
+    std::string KilledByWhat;
+};
+
+}
+
+#endif

include/Engine/Core/EPlayerHealthPickup.h

@@ -0,0 +1,18 @@
+#ifndef EPlayerHealthPickup_h__
+#define EPlayerHealthPickup_h__
+
+#include "EventBroker.h"
+#include "../Core/Entity.h"
+
+namespace Events
+{
+
+struct PlayerHealthPickup : Event
+{
+    double HealthAmount;
+    EntityID PlayerHealedID;
+};
+
+}
+
+#endif

include/Engine/Core/Entity.h

@@ -2,5 +2,6 @@
 #define Entity_h__
 
 typedef unsigned int EntityID;
+const static unsigned int EntityID_Invalid = -1;
 
 #endif

include/Engine/Core/EntityFile.h

@@ -0,0 +1,293 @@
+#ifndef EntityFile_h__
+#define EntityFile_h__
+
+#include <stack>
+#include <boost/lexical_cast.hpp>
+#include <xercesc/util/XercesDefs.hpp>
+#include <xercesc/util/PlatformUtils.hpp>
+#include <xercesc/sax2/SAX2XMLReader.hpp>
+#include <xercesc/sax2/XMLReaderFactory.hpp>
+#include <xercesc/sax2/DefaultHandler.hpp>
+#include <xercesc/sax2/Attributes.hpp>
+#include <xercesc/util/XMLString.hpp>
+#include <xercesc/util/XMLChar.hpp>
+#include <xercesc/sax2/DefaultHandler.hpp>
+#include <xercesc/framework/XMLDocumentHandler.hpp>
+#include <xercesc/framework/psvi/XSElementDeclaration.hpp>
+#include <xercesc/framework/psvi/XSComplexTypeDefinition.hpp>
+#include <xercesc/framework/psvi/XSParticle.hpp>
+#include <xercesc/framework/psvi/XSModelGroup.hpp>
+#include <xercesc/framework/psvi/XSAnnotation.hpp>
+#include <xercesc/framework/psvi/XSValue.hpp>
+#include <xercesc/framework/XMLGrammarPoolImpl.hpp>
+#include <xercesc/dom/DOM.hpp>
+#include <xercesc/dom/DOMLSInput.hpp>
+#include <xercesc/dom/DOMElement.hpp>
+
+#include "../GLM.h"
+#include "Util/XercesString.h"
+#include "ResourceManager.h"
+#include "Entity.h"
+#include "ComponentInfo.h"
+
+class EntityFileHandler
+{
+    friend class EntityFileSAXHandler;
+public:
+    // @param EntityID The entity found
+    // @param EntityID The parent of the entity
+    typedef std::function<void(EntityID, EntityID, const std::string&)> OnStartEntityCallback;
+    void SetStartEntityCallback(OnStartEntityCallback c) { m_OnStartEntityCallback = c; }
+    // @param EntityID The entity the component corresponds to
+    // @param std::string Type name of the component
+    typedef std::function<void(EntityID, const std::string&)> OnStartComponentCallback;
+    void SetStartComponentCallback(OnStartComponentCallback c) { m_OnStartComponentCallback = c; }
+    // @param EntityID Entity 
+    // @param std::string Component name 
+    // @param std::string Field name
+    // @param std::map<std::string, std::string> Field attribute names and values
+    typedef std::function<void(EntityID, const std::string&, const std::string&, const std::map<std::string, std::string>&)> OnStartFieldCallback;
+    void SetStartFieldCallback(OnStartFieldCallback c) { m_OnStartFieldCallback = c; }
+    // @param EntityID Entity 
+    // @param std::string Component name 
+    // @param std::string Field name
+    // @param char* Field data
+    typedef std::function<void(EntityID, const std::string&, const std::string&, const char*)> OnStartFieldDataCallback;
+    void SetStartFieldDataCallback(OnStartFieldDataCallback c) { m_OnStartFieldDataCallback = c; }
+
+private:
+    OnStartEntityCallback m_OnStartEntityCallback = nullptr;
+    OnStartComponentCallback m_OnStartComponentCallback = nullptr;
+    OnStartFieldCallback m_OnStartFieldCallback = nullptr;
+    OnStartFieldDataCallback m_OnStartFieldDataCallback = nullptr;
+};
+
+class EntityFileSAXHandler : public xercesc::DefaultHandler
+{
+public:
+    enum class State
+    {
+        Unknown,
+        Entity,
+        Component,
+        ComponentField
+    };
+
+    EntityFileSAXHandler(const EntityFileHandler* handler, xercesc::SAX2XMLReader* reader)
+        : m_Handler(handler)
+        , m_Reader(reader)
+    {
+        // 0 is imaginary world entity
+        m_EntityStack.push(0);
+        m_StateStack.push(State::Unknown);
+    }
+
+    void startElement(const XMLCh* const _uri, const XMLCh* const _localName, const XMLCh* const _qname, const xercesc::Attributes& attrs) override
+    {
+        std::string name = XS::ToString(_localName);
+
+        if (m_StateStack.top() == State::Unknown || m_StateStack.top() == State::Entity) {
+            if (name == "Entity") {
+                m_StateStack.push(State::Entity);
+                onStartEntity(attrs);
+                return;
+            }
+            if (name == "EntityRef") {
+                onStartEntityRef(attrs);
+                return;
+            }
+        }
+
+        std::string uri = XS::ToString(_uri);
+        if (m_StateStack.top() == State::Entity) {
+            if (uri == "components") {
+                m_StateStack.push(State::Component);
+                onStartComponent(name);
+                return;
+            }
+        }
+        
+        if (m_StateStack.top() == State::Component) {
+            m_StateStack.push(State::ComponentField);
+            onStartComponentField(name, attrs);
+            return;
+        }
+    }
+
+    void characters(const XMLCh* const chars, const XMLSize_t length) override
+    {
+        if (m_StateStack.top() == State::ComponentField) {
+            char* transcoded = xercesc::XMLString::transcode(chars);
+            onFieldData(transcoded);
+        }
+    }
+
+    void endElement(const XMLCh* const _uri, const XMLCh* const _localName, const XMLCh* const _qname) override
+    {
+        std::string name = XS::ToString(_localName);
+        if (m_StateStack.top() == State::Entity) {
+            if (name == "Entity") {
+                m_StateStack.pop();
+                onEndEntity();
+                return;
+            }
+        }
+        
+        std::string uri = XS::ToString(_uri);
+        if (m_StateStack.top() == State::Component) {
+            //if (uri == "components") {
+                m_StateStack.pop();
+                onEndComponent(name);
+                return;
+            //}
+        }
+
+        if (m_StateStack.top() == State::ComponentField) {
+            m_StateStack.pop();
+            onEndComponentField(name);
+            return;
+        }
+    }
+
+    void fatalError(const xercesc::SAXParseException& e) 
+    {
+        XS::ToString s(e.getMessage());
+        LOG_ERROR("SAXParseException: %s", ((std::string)s).c_str());
+        //throw e;
+    }
+
+private:
+    const EntityFileHandler* m_Handler;
+    xercesc::XMLGrammarPool* m_GrammarPool;
+    xercesc::SAX2XMLReader* m_Reader;
+    //State m_CurrentScope = State::Unknown;
+    std::stack<State> m_StateStack;
+    unsigned int m_NextEntityID = 0;
+    std::stack<EntityID> m_EntityStack;
+    std::string m_CurrentComponent;
+    std::string m_CurrentField;
+    std::map<std::string, std::string> m_CurrentAttributes;
+
+    void onStartEntity(const xercesc::Attributes& attrs) 
+    {
+        EntityID parent = m_EntityStack.top();
+
+        if (m_Handler->m_OnStartEntityCallback) {
+            std::string name;
+            auto xName = attrs.getValue(XS::ToXMLCh("name"));
+            if (xName != nullptr) {
+                name = XS::ToString(xName);
+            }
+            m_Handler->m_OnStartEntityCallback(m_NextEntityID, parent, name);
+        }
+
+        m_EntityStack.push(m_NextEntityID);
+        m_NextEntityID++;
+    } 
+    void onEndEntity()
+    {
+        m_EntityStack.pop();
+    }
+    void onStartEntityRef(const xercesc::Attributes& attrs)
+    {
+        std::string path = XS::ToString(attrs.getValue(XS::ToXMLCh("file")));
+        
+        xercesc::SAX2XMLReader* parser = xercesc::XMLReaderFactory::createXMLReader();
+        parser->setContentHandler(this);
+        parser->setErrorHandler(this);
+        parser->parse(path.c_str());
+        delete parser;
+    }
+    void onStartComponent(const std::string& name)
+    {
+        //LOG_DEBUG("    Component: %s", name.c_str());
+        m_CurrentComponent = name;
+        if (m_Handler->m_OnStartComponentCallback) {
+            m_Handler->m_OnStartComponentCallback(m_EntityStack.top(), name);
+        }
+    }
+    void onEndComponent(const std::string& name) { }
+    void onStartComponentField(const std::string& field, const xercesc::Attributes& attrs) 
+    {
+        //LOG_DEBUG("        Field: %s", field.c_str());
+        m_CurrentField = field;
+        m_CurrentAttributes.clear();
+        for (int i = 0; i < attrs.getLength(); i++) {
+            auto name = attrs.getQName(i);
+            auto value = attrs.getValue(name);
+            //LOG_DEBUG("            %s = %s", (char*)XS::ToString(name), (char*)XS::ToString(value));
+            m_CurrentAttributes[XS::ToString(name).operator std::string()] = XS::ToString(value).operator std::string();
+        }
+
+        if (m_Handler->m_OnStartFieldCallback) {
+            m_Handler->m_OnStartFieldCallback(m_EntityStack.top(), m_CurrentComponent, field, m_CurrentAttributes);
+        }
+    }
+    void onEndComponentField(const std::string& field) { }
+
+    void onFieldData(char* data)
+    {
+        //LOG_DEBUG("            Data: %s", data);
+
+        if (m_Handler->m_OnStartFieldDataCallback) {
+            m_Handler->m_OnStartFieldDataCallback(m_EntityStack.top(), m_CurrentComponent, m_CurrentField, data);
+        }
+
+        xercesc::XMLString::release(&data);
+    }
+};
+
+class EntityFileXMLErrorHandler : public xercesc::ErrorHandler
+{
+public:
+	void warning(const xercesc::SAXParseException& e) override
+	{
+		reportParseException("Warning", e);
+	}
+	void error(const xercesc::SAXParseException& e) override
+	{
+		reportParseException("Error", e);
+	}
+	void fatalError(const xercesc::SAXParseException& e) override
+	{
+		reportParseException("FATAL ERROR", e);
+	}
+	void resetErrors() override { }
+
+private:
+	void reportParseException(std::string type, const xercesc::SAXParseException& e)
+	{
+		char* message = xercesc::XMLString::transcode(e.getMessage());
+		char* systemID = xercesc::XMLString::transcode(e.getSystemId());
+		std::cerr << systemID << ":" << e.getLineNumber() << ":" << e.getColumnNumber() << std::endl;
+		std::cerr << type << ": " << message << std::endl;
+		xercesc::XMLString::release(&systemID);
+		xercesc::XMLString::release(&message);
+	}
+};
+
+class EntityFile : public Resource
+{
+    friend class ResourceManager;
+private:
+    EntityFile(boost::filesystem::path path);
+    ~EntityFile();
+
+public:
+    static std::size_t GetTypeStride(std::string typeName);
+    static void WriteAttributeData(char* outData, const ComponentInfo::Field_t& field, const std::map<std::string, std::string>& attributes);
+    static void WriteValueData(char* outData, const ComponentInfo::Field_t& field, const char* valueData);
+
+    xercesc::XMLGrammarPool* GrammarPool() const { return m_GrammarPool; }
+
+    void Parse(const EntityFileHandler* handler) const;
+
+private:
+    boost::filesystem::path m_FilePath;
+    xercesc::XMLGrammarPool* m_GrammarPool;
+    xercesc::SAX2XMLReader* m_SAX2XMLReader;
+	//std::map<std::string, ::ComponentInfo> m_ComponentInfo;
+    //std::vector<std::string> m_EntityReferences;
+};
+
+#endif

include/Engine/Core/EntityFileParser.h

@@ -0,0 +1,28 @@
+#ifndef EntityFileParser_h__
+#define EntityFileParser_h__
+
+#include "EntityFile.h"
+#include "World.h"
+
+class EntityFileParser
+{
+public:
+    EntityFileParser(const EntityFile* entityFile);
+
+    void MergeEntities(World* world);
+
+private:
+    const EntityFile* m_EntityFile;
+    EntityFileHandler m_Handler;
+    World* m_World = nullptr;
+    // Maps EntityIDs local to the file to real IDs in the world after they've been 
+    // created in order to resolve parent-child relationships.
+    std::map<EntityID, EntityID> m_EntityIDMapper;
+
+    void onStartEntity(EntityID entity, EntityID parent, const std::string& name);
+    void onStartComponent(EntityID entity, const std::string& component);
+    void onStartComponentField(EntityID entity, const std::string& componentType, const std::string& fieldName, const std::map<std::string, std::string>& attributes);
+    void onFieldData(EntityID entity, const std::string& componentType, const std::string& fieldName, const char* fieldData);
+};
+
+#endif

include/Engine/Core/EntityFilePreprocessor.h

@@ -0,0 +1,36 @@
+#ifndef EntityFilePreprocessor_h__
+#define EntityFilePreprocessor_h__
+
+#include <xercesc/framework/psvi/XSElementDeclaration.hpp>
+#include <xercesc/framework/psvi/XSComplexTypeDefinition.hpp>
+#include <xercesc/framework/psvi/XSParticle.hpp>
+#include <xercesc/framework/psvi/XSModelGroup.hpp>
+#include <xercesc/framework/psvi/XSAnnotation.hpp>
+#include <xercesc/framework/psvi/XSValue.hpp>
+#include <xercesc/framework/MemBufFormatTarget.hpp>
+#include <xercesc/framework/MemBufInputSource.hpp>
+#include <xercesc/parsers/XercesDOMParser.hpp>
+
+#include "Util/XercesString.h"
+#include "ResourceManager.h"
+#include "World.h"
+#include "EntityFile.h"
+
+class EntityFilePreprocessor
+{
+public:
+    EntityFilePreprocessor(const EntityFile* entityFile);
+
+    void RegisterComponents(World* world);
+
+private:
+    const EntityFile* m_EntityFile;
+    std::map<std::string, unsigned int> m_ComponentCounts;
+	std::map<std::string, ComponentInfo> m_ComponentInfo;
+
+	void onStartComponent(EntityID entity, std::string type);
+    void parseComponentInfo();
+    void parseDefaults();
+};
+
+#endif

include/Engine/Core/EntityFileWriter.h

@@ -0,0 +1,39 @@
+#ifndef EntityFileWriter_h__
+#define EntityFileWriter_h__
+
+#include <boost/filesystem.hpp>
+#include <xercesc/dom/DOM.hpp>
+#include <xercesc/util/XMLString.hpp>
+#include <xercesc/util/PlatformUtils.hpp>
+#include <xercesc/framework/LocalFileFormatTarget.hpp>
+
+#include "Util/XercesString.h"
+#include "EntityFile.h"
+#include "World.h"
+
+class EntityFileWriter
+{
+public:
+    EntityFileWriter(boost::filesystem::path file)
+        : m_FilePath(file)
+    {
+        using namespace xercesc;
+        m_DOMImplementation = DOMImplementationRegistry::getDOMImplementation(XS::ToXMLCh("LS"));
+        m_DOMLSSerializer = static_cast<DOMImplementationLS*>(m_DOMImplementation)->createLSSerializer();
+        m_DOMLSSerializer->getDomConfig()->setParameter(XMLUni::fgDOMWRTDiscardDefaultContent, true);
+        m_DOMLSSerializer->getDomConfig()->setParameter(XMLUni::fgDOMWRTFormatPrettyPrint, true);
+    }
+
+    void WriteWorld(World* world);
+    void WriteEntity(World* world, EntityID entity);
+
+private:
+    boost::filesystem::path m_FilePath;
+    xercesc::DOMImplementation* m_DOMImplementation;
+    xercesc::DOMLSSerializer* m_DOMLSSerializer;
+
+    void appendEntityChildren(xercesc::DOMElement* parentElement, const World* world, EntityID entity);
+    void appentEntityComponents(xercesc::DOMElement* parentElemetn, const World* world, EntityID entity);
+};
+
+#endif

include/Engine/Core/EntityXMLFile.h

@@ -1,141 +0,0 @@
-#ifndef EntityXMLFile_h__
-#define EntityXMLFile_h__
-
-#include <sstream>
-
-#include "../Common.h"
-#include "../GLM.h"
-#include <xercesc/dom/DOM.hpp>
-#include <xercesc/dom/DOMLSInput.hpp>
-#include <xercesc/dom/DOMElement.hpp>
-#include <xercesc/framework/Wrapper4InputSource.hpp>
-#include <xercesc/framework/LocalFileInputSource.hpp>
-#include <xercesc/framework/LocalFileFormatTarget.hpp>
-#include <xercesc/framework/MemBufFormatTarget.hpp>
-#include <xercesc/framework/MemBufInputSource.hpp>
-#include <xercesc/sax/HandlerBase.hpp>
-#include <xercesc/util/PlatformUtils.hpp>
-#include <xercesc/util/XMLFloat.hpp>
-#include <xercesc/framework/XMLGrammarPoolImpl.hpp>
-#include <xercesc/parsers/XercesDOMParser.hpp>
-#include <xercesc/framework/psvi/XSElementDeclaration.hpp>
-#include <xercesc/framework/psvi/XSComplexTypeDefinition.hpp>
-#include <xercesc/framework/psvi/XSParticle.hpp>
-#include <xercesc/framework/psvi/XSModelGroup.hpp>
-#include <xercesc/framework/psvi/XSAnnotation.hpp>
-#include <xercesc/framework/psvi/XSValue.hpp>
-#include <xercesc/framework/XMLValidator.hpp>
-
-#include "ResourceManager.h"
-#include "Entity.h"
-#include "ComponentInfo.h"
-class World;
-
-class EntityPreprocessorXMLErrorHandler : public xercesc::DOMErrorHandler
-{
-public:
-	bool handleError(const xercesc::DOMError &e) override
-	{
-		char* message = xercesc::XMLString::transcode(e.getMessage());
-		std::cerr << "Preprocessor DOMError: " << message << std::endl;
-		xercesc::XMLString::release(&message);
-		return false;
-	}
-};
-
-class EntityParserXMLErrorHandler : public xercesc::ErrorHandler
-{
-public:
-	void warning(const xercesc::SAXParseException& e) override
-	{
-		reportParseException("Warning", e);
-	}
-	void error(const xercesc::SAXParseException& e) override
-	{
-		reportParseException("Error", e);
-	}
-	void fatalError(const xercesc::SAXParseException& e) override
-	{
-		reportParseException("FATAL ERROR", e);
-	}
-	void resetErrors() override { }
-
-private:
-	void reportParseException(std::string type, const xercesc::SAXParseException& e)
-	{
-		char* message = xercesc::XMLString::transcode(e.getMessage());
-		char* systemID = xercesc::XMLString::transcode(e.getSystemId());
-		std::cerr << systemID << ":" << e.getLineNumber() << ":" << e.getColumnNumber() << std::endl;
-		std::cerr << type << ": " << message << std::endl;
-		xercesc::XMLString::release(&systemID);
-		xercesc::XMLString::release(&message);
-	}
-};
-
-class XSTR
-{
-public:
-	XSTR(const XMLCh* const xmlString) 
-	{
-		m_AsChar = xercesc::XMLString::transcode(xmlString);
-	}
-
-	XSTR(const char* normalString)
-	{
-		m_AsXMLCh = xercesc::XMLString::transcode(normalString);
-	}
-
-	~XSTR()
-	{
-		if (m_AsChar != nullptr) {
-			xercesc::XMLString::release(&m_AsChar);
-		}
-		if (m_AsXMLCh != nullptr) {
-			xercesc::XMLString::release(&m_AsXMLCh);
-		}
-	}
-
-	operator const char*() const { return m_AsChar; }
-	operator const XMLCh*() const { return m_AsXMLCh; }
-
-private:
-	char* m_AsChar = nullptr;
-	XMLCh* m_AsXMLCh = nullptr;
-};
-
-class EntityXMLFile : public Resource
-{
-	friend class ResourceManager;
-
-private:
-	EntityXMLFile(std::string path);
-
-public:
-    ~EntityXMLFile();
-
-    void PopulateWorld(World* world);
-
-private:
-    static unsigned int InstanceCount;
-
-	std::string m_EntityFile;
-	xercesc::XMLGrammarPool* m_GrammarPool = nullptr;
-	EntityParserXMLErrorHandler* m_ErrorHandler = nullptr;
-	xercesc::XercesDOMParser* m_DOMParser = nullptr;
-	xercesc::DOMDocument* m_DOMDocument = nullptr;
-	std::map<std::string, ComponentInfo> m_ComponentInfo;
-
-    // Preprocesses the entity file to insert include-by-copy child entities
-    // TODO: Make this work in memory instead of saving to file
-    void preprocess(std::string inPath, std::string outPath);
-
-    void parseComponentInfo();
-    void parseDefaults();
-    void predictComponentAllocation();
-    void parseEntityGraph(World* world, xercesc::DOMElement* parent, EntityID parentEntity);
-    std::size_t getTypeStride(std::string typeName);
-    float getFloatAttribute(const xercesc::DOMElement* element, const char* attribute) const;
-    void writeData(const xercesc::DOMElement* element, std::string typeName, char* outData);
-};
-
-#endif

include/Engine/Core/EventBroker.h

@@ -13,6 +13,8 @@
 	relay = decltype(relay)(std::bind(handler, this, std::placeholders::_1)); \
 	m_EventBroker->Subscribe(relay);
 
+typedef unsigned int EventID;
+
 class EventBroker;
 
 class BaseEventRelay
@@ -31,6 +33,7 @@ public:
     virtual bool Receive(const std::shared_ptr<Event> event) = 0;
 
 protected:
+    EventID m_EventID;
     std::string m_ContextTypeName;
     std::string m_EventTypeName;
     EventBroker* m_Broker;
@@ -95,6 +98,7 @@ public:
 
 private:
     bool m_IsProcessing = false;
+    EventID m_NextEventID = 0;
 
     typedef std::string ContextTypeName_t; // typeid(ContextType).name()
     typedef std::string EventTypeName_t; // typeid(EventType).name()
@@ -103,14 +107,14 @@ private:
     typedef std::unordered_map<ContextTypeName_t, EventRelays_t> ContextRelays_t;
     ContextRelays_t m_ContextRelays;
     std::vector<BaseEventRelay*> m_RelaysToSubscribe;
-    std::vector<BaseEventRelay*> m_RelaysToUnsubscribe;
+    std::vector<std::tuple<EventID, ContextTypeName_t, EventTypeName_t>> m_RelaysToUnsubscribe;
 
     typedef std::list<std::pair<EventTypeName_t, std::shared_ptr<Event>>> EventQueue_t;
     std::shared_ptr<EventQueue_t> m_EventQueueRead;
     std::shared_ptr<EventQueue_t> m_EventQueueWrite;
 
     void subscribeImmediate(BaseEventRelay& relay);
-    void unsubscribeImmediate(BaseEventRelay& relay);
+    void unsubscribeImmediate(std::tuple<EventID, ContextTypeName_t, EventTypeName_t> identifier);
 };
 
 template <typename EventType>

include/Engine/Core/InputManager.h

@@ -16,6 +16,7 @@
 #include "ELockMouse.h"
 #include "EGamepadAxis.h"
 #include "EGamepadButton.h"
+#include "EFileDropped.h"
 
 class InputManager
 {
@@ -71,6 +72,8 @@ private:
     static void GLFWCharCallback(GLFWwindow* window, unsigned int c);
     static std::vector<std::pair<double, double>> GLFWScrollCallbackQueue;
     static void GLFWScrollCallback(GLFWwindow* window, double xoffset, double yoffset);
+    static std::vector<std::string> GLFWDropCallbackQueue;
+    static void GLFWDropCallback(GLFWwindow* window, int count, const char* paths[]);
 };
 
 #endif

include/Engine/Core/MemoryPool.h

@@ -253,7 +253,7 @@ public:
 	}
 
 	//Postfix increment i.e. iter++. Prefer pre-increment (++iter) for efficiency.
-	MemoryPoolForwardIterator& operator++(int)
+	MemoryPoolForwardIterator operator++(int)
 	{
 		MemoryPoolForwardIterator<T> copyIter(*this);
 		operator++();

include/Engine/Core/OctTree.h

@@ -0,0 +1,104 @@
+#ifndef OctTree_h__
+#define OctTree_h__
+
+#include "Core/AABB.h"
+
+class Ray;
+
+class OctTree
+{
+public:
+    struct Output
+    {
+        float CollideDistance;
+    };
+
+    OctTree();
+    ~OctTree();
+    //For the root OctTree, [octTreeBounds] should be a box containing the entire level.
+    OctTree(const AABB& octTreeBounds, int subDivisions);
+
+    //We cannot copy the OctTree as of now, because of the recursive dynamic allocation.
+    //Define these if the OctTree suddenly needs to be copied, think of the children OctChild* ptrs. 
+    OctTree(const OctTree& other) = delete;
+    OctTree(const OctTree&& other) = delete;
+    OctTree& operator= (const OctTree& other) = delete;
+    //Add a dynamic object (one that moves around) into the tree.
+    void AddDynamicObject(const AABB& box);
+    //Add a static object (that does not move) into the tree.
+    void AddStaticObject(const AABB& box);
+    //Get the boxes that are in the same area as the input [box], the boxes are put in [outBoxes].
+    void BoxesInSameRegion(const AABB& box, std::vector<AABB>& outBoxes);
+    //Empty the tree of all objects, static and dynamic.
+    void ClearObjects();
+    //Empty the tree of all dynamic objects. Static objects remain in the tree.
+    void ClearDynamicObjects();
+
+    //Returns true if the ray collides with something in the tree. Result is written to [data].
+    bool RayCollides(const Ray& ray, Output& data);
+    //Returns true if the box collides with something in the tree. 
+    //On collision with a box, that box is written to [outBoxIntersected].
+    //Note: More efficient than calling BoxesInSameRegion from outside and testing there.
+    bool BoxCollides(const AABB& boxToTest, AABB& outBoxIntersected);
+
+private:
+    struct OctChild;    //Fwd declaration;
+    struct ContainedObject
+    {
+        ContainedObject()
+            : Box(AABB())
+            , Checked(false)
+        {}
+        ContainedObject(AABB box)
+            : Box(box)
+            , Checked(false)
+        {}
+        AABB Box;
+        bool Checked;
+    };
+    OctChild* m_Root;
+    std::vector<ContainedObject> m_StaticObjects;
+    std::vector<ContainedObject> m_DynamicObjects;
+
+    bool m_UpdatedOnce;
+    unsigned int m_BoxID;
+    glm::vec3 m_PrevPos;
+    glm::quat m_PrevOri;
+
+    void falsifyObjectChecks();
+
+    struct OctChild
+    {
+        ~OctChild();
+        OctChild(const AABB& octTreeBounds, 
+            int subDivisions, 
+            std::vector<OctTree::ContainedObject>& staticObjects, 
+            std::vector<OctTree::ContainedObject>& dynamicObjects);
+        OctChild(const OctChild& other) = delete;
+        OctChild(const OctChild&& other) = delete;
+        OctChild& operator= (const OctChild& other) = delete;
+        void AddDynamicObject(const AABB& box);
+        void AddStaticObject(const AABB& box);
+        void BoxesInSameRegion(const AABB& box, std::vector<AABB>& outBoxes) const;
+        void ClearObjects();
+        void ClearDynamicObjects();
+        bool RayCollides(const Ray& ray, Output& data) const;
+        bool BoxCollides(const AABB& boxToTest, AABB& outBoxIntersected) const;
+
+        OctChild* m_Children[8];
+        //Indices into the lists in OctTree.
+        std::vector<int> m_StaticObjIndices;
+        std::vector<int> m_DynamicObjIndices;
+        AABB m_Box;
+        //Reference to the lists in OctTree.
+        std::vector<OctTree::ContainedObject>& m_StaticObjectsRef;
+        std::vector<OctTree::ContainedObject>& m_DynamicObjectsRef;
+
+        inline bool hasChildren() const;
+        int childIndexContainingPoint(const glm::vec3& point) const;
+        std::vector<int> childIndicesContainingBox(const AABB& box) const;
+    };
+};
+
+
+#endif

include/Engine/Core/Ray.h

@@ -0,0 +1,31 @@
+#ifndef Ray_h__
+#define Ray_h__
+
+#include "../GLM.h"
+#include "Common.h"
+
+class Ray
+{
+public:
+    Ray(const glm::vec3& origin, const glm::vec3& dir)
+        : m_Origin(origin)
+        , m_Direction(glm::normalize(dir))
+    {
+        DEBUG_IF(true) {
+            if (glm::any(glm::isnan(m_Direction))) {
+                LOG_WARNING("Ray Direction was set to the zero-vector, expect unknown side effects and/or crashes.");
+            }
+        }
+    }
+    const glm::vec3& Origin() const { return m_Origin; }
+    const glm::vec3& Direction() const { return m_Direction; }
+    //Sets the ray origin at parameter.
+    void SetOrigin(const glm::vec3& origin) { m_Origin = origin; }
+    //Normalizes the parameter and sets direction to it.
+    void SetDirection(const glm::vec3& direction) { m_Direction = glm::normalize(direction); }
+private:
+    glm::vec3 m_Origin;
+    glm::vec3 m_Direction;
+};
+
+#endif // Ray_h__

include/Engine/Core/System.h

@@ -7,10 +7,13 @@
 
 class System
 {
+    friend class SystemPipeline;
+
 protected:
     System(EventBroker* eventBroker)
         : m_EventBroker(eventBroker)
     { }
+    virtual ~System() = default;
 
     EventBroker* m_EventBroker;
 };
@@ -24,6 +27,7 @@ protected:
         : System(eventBroker)
         , m_ComponentType(componentType)
     { }
+    virtual ~PureSystem() = default;
 
     const std::string m_ComponentType;
 
@@ -38,6 +42,7 @@ protected:
     ImpureSystem(EventBroker* eventBroker)
         : System(eventBroker)
     { }
+    virtual ~ImpureSystem() = default;
 
     virtual void Update(World* world, double dt) = 0;
 };

include/Engine/Core/SystemPipeline.h

@@ -14,23 +14,28 @@ public:
     { }
     ~SystemPipeline()
     {
-        for (auto& pair : m_PureSystems) {
-            for (auto& system : pair.second) {
-                delete system;
+        for (UnorderedSystems& group : m_OrderedSystemGroups) {
+            for (auto& pair : group.Systems) {
+                delete pair.second;
             }
         }
     }
 
     template <typename T, typename... Arguments>
-    void AddSystem(Arguments... args)
+    //All systems with orderlevel 0 will be updated first, then 1, 2, etc.
+    void AddSystem(int updateOrderLevel, Arguments... args)
     {
+        if (updateOrderLevel + 1 > m_OrderedSystemGroups.size()) {
+            m_OrderedSystemGroups.resize(updateOrderLevel + 1);
+        }
+        UnorderedSystems& group = m_OrderedSystemGroups[updateOrderLevel];
         System* system = new T(m_EventBroker, args...);
-        m_Systems[typeid(T).name()] = system;
+        group.Systems[typeid(T).name()] = system;
 
         if (std::is_base_of<PureSystem, T>::value) {
             PureSystem* pureSystem = static_cast<PureSystem*>(system);
             if (!pureSystem->m_ComponentType.empty()) {
-                m_PureSystems[pureSystem->m_ComponentType].push_back(pureSystem);
+                group.PureSystems[pureSystem->m_ComponentType].push_back(pureSystem);
             } else {
                 LOG_ERROR("Failed to add pure system \"%s\": Missing component type!", typeid(T).name());
             }
@@ -38,41 +43,47 @@ public:
 
         if (std::is_base_of<ImpureSystem, T>::value) {
             ImpureSystem* impureSystem = static_cast<ImpureSystem*>(system);
-            m_ImpureSystems.push_back(impureSystem);
+            group.ImpureSystems.push_back(impureSystem);
         }
     }
 
     void Update(World* world, double dt)
     {
-        // Process events
-        for (auto& pair : m_Systems) {
-            m_EventBroker->Process(pair.first);
-        }
-
-        // Update
-        for (auto& pair : m_PureSystems) {
-            const std::string& componentName = pair.first;
-            auto& systems = pair.second;
-            const ComponentPool* pool = world->GetComponents(componentName);
-            if (pool == nullptr) {
-                continue;
+        for (UnorderedSystems& group : m_OrderedSystemGroups) {
+            // Process events
+            for (auto& pair : group.Systems) {
+                m_EventBroker->Process(pair.first);
             }
-            for (auto& component : *pool) {
-                for (auto& system : systems) {
-                    system->UpdateComponent(world, component, dt);
+
+            // Update
+            for (auto& pair : group.PureSystems) {
+                const std::string& componentName = pair.first;
+                auto& systems = pair.second;
+                const ComponentPool* pool = world->GetComponents(componentName);
+                if (pool == nullptr) {
+                    continue;
+                }
+                for (auto& component : *pool) {
+                    for (auto& system : systems) {
+                        system->UpdateComponent(world, component, dt);
+                    }
                 }
             }
-        }
-        for (auto& system : m_ImpureSystems) {
-            system->Update(world, dt);
+            for (auto& system : group.ImpureSystems) {
+                system->Update(world, dt);
+            }
         }
     }
 
 private:
     EventBroker* m_EventBroker;
-    std::map<std::string, System*> m_Systems;
-    std::map<std::string, std::vector<PureSystem*>> m_PureSystems;
-    std::vector<ImpureSystem*> m_ImpureSystems;
+    struct UnorderedSystems
+    {
+        std::map<std::string, System*> Systems;
+        std::map<std::string, std::vector<PureSystem*>> PureSystems;
+        std::vector<ImpureSystem*> ImpureSystems;
+    };
+    std::vector<UnorderedSystems> m_OrderedSystemGroups;
 };
 
 #endif

include/Engine/Core/Util/IfDebug.h

@@ -0,0 +1,12 @@
+// Example:
+// DEBUG_IF(condition) {
+//    // This code is executed only in debug mode and if condition is true.
+// }
+// NOTE: condition statement is not executed at all in release mode.
+#ifndef DEBUG_IF
+#ifndef DEBUG
+#define DEBUG_IF(c) if(c)
+#else
+#define DEBUG_IF(c) if(false)
+#endif
+#endif

include/Engine/Core/Util/XercesString.h

@@ -0,0 +1,46 @@
+#ifndef Util_XercesString_h__
+#define Util_XercesString_h__
+
+#include <string>
+#include <xercesc/util/XercesDefs.hpp>
+#include <xercesc/util/XMLString.hpp>
+
+namespace XS
+{
+
+class ToString
+{
+public:
+    ToString(const XMLCh* const str) { m_AsChar = xercesc::XMLString::transcode(str); }
+    ~ToString()
+    {
+        if (m_AsChar != nullptr) {
+            xercesc::XMLString::release(&m_AsChar);
+        }
+    }
+
+    operator std::string() const { return std::string(m_AsChar); }
+private:
+    char* m_AsChar = nullptr;
+};
+
+class ToXMLCh
+{
+public:
+    ToXMLCh(const std::string str) { m_Transcoded = xercesc::XMLString::transcode(str.c_str()); }
+    ToXMLCh(const char* str) { m_Transcoded = xercesc::XMLString::transcode(str); }
+    ~ToXMLCh()
+    {
+        if (m_Transcoded != nullptr) {
+            xercesc::XMLString::release(&m_Transcoded);
+        }
+    }
+
+    operator const XMLCh*() const { return m_Transcoded; }
+private:
+    XMLCh* m_Transcoded = nullptr;
+};
+
+}
+
+#endif

include/Engine/Core/World.h

@@ -16,13 +16,14 @@ public:
     EntityID CreateEntity(EntityID parent = 0);
     // Delete entity and all components within
     void DeleteEntity(EntityID entity);
-
+    // Check if an entity exists
+    bool ValidEntity(EntityID entity) const;
     // Register a component type and allocate space for it
     void RegisterComponent(ComponentInfo& ci);
     // Attach a component to an entity and fill it with default values
     ComponentWrapper AttachComponent(EntityID entity, std::string componentType);
     // Check if an entity has a component
-    bool HasComponent(EntityID entity, std::string componentType);
+    bool HasComponent(EntityID entity, std::string componentType) const;
     // Get a component of an entity
     ComponentWrapper GetComponent(EntityID entity, std::string componentType);
     // Delete a component off an entity
@@ -37,14 +38,19 @@ public:
     const std::unordered_map<std::string, ComponentPool*>& GetComponentPools() const { return m_ComponentPools; }
     // Get the entity children map
     const std::unordered_multimap<EntityID, EntityID>& GetEntityChildren() const { return m_EntityChildren; }
+    // Set the textual name of an entity
+    void SetName(EntityID entity, const std::string& name);
+    // Get the textual name of an entity
+    std::string GetName(EntityID entity) const;
 
 private:
-    EntityID m_CurrentEntityID = 1;
+    EntityID m_CurrentEntityID = 0;
 
     std::unordered_map<EntityID, EntityID> m_EntityParents;
     // TODO: This should be a more effective structure
     std::unordered_multimap<EntityID, EntityID> m_EntityChildren;
     std::unordered_map<std::string, ComponentPool*> m_ComponentPools;
+    std::unordered_map<EntityID, std::string> m_EntityNames;
 
     EntityID generateEntityID();
 };

include/Engine/Editor/EditorSystem.h

@@ -1,5 +1,7 @@
 #include <imgui/imgui.h>
 #include <glm/gtx/common.hpp>
+#include <boost/filesystem/path.hpp>
+#include <nativefiledialog/nfd.h>
 #include "../Core/System.h"
 #include "../Core/EMousePress.h"
 #include "../Core/EMouseRelease.h"
@@ -8,6 +10,10 @@
 #include "../Input/EInputCommand.h"
 #include "../Rendering/IRenderer.h"
 #include "../Rendering/RenderSystem.h"
+#include "../Core/EFileDropped.h"
+#include "../Core/EntityFilePreprocessor.h"
+#include "../Core/EntityFileParser.h"
+#include "../Core/EntityFileWriter.h"
 
 class EditorSystem : public ImpureSystem
 {
@@ -22,6 +28,8 @@ private:
 
     bool m_Enabled;
     bool m_Visible;
+    boost::filesystem::path m_DefaultEntityDir;
+    boost::filesystem::path m_CurrentFile;
     std::vector<glm::vec2> m_PickingQueue;
 
     enum class WidgetMode
@@ -38,17 +46,25 @@ private:
         Global
     } m_WidgetSpace = WidgetSpace::Global;
 
-    EntityID m_Widget = 0;
-    EntityID m_WidgetX = 0;
-    EntityID m_WidgetY = 0;
-    EntityID m_WidgetZ = 0;
-    EntityID m_WidgetOrigin = 0;
+    EntityID m_Widget = EntityID_Invalid;
+    EntityID m_WidgetX = EntityID_Invalid;
+    EntityID m_WidgetPlaneX = EntityID_Invalid;
+    EntityID m_WidgetY = EntityID_Invalid;
+    EntityID m_WidgetPlaneY = EntityID_Invalid;
+    EntityID m_WidgetZ = EntityID_Invalid;
+    EntityID m_WidgetPlaneZ = EntityID_Invalid;
+    EntityID m_WidgetOrigin = EntityID_Invalid;
     glm::vec3 m_WidgetCurrentAxis;
     float m_WidgetPickingDepth = 0.f;
 
-    EntityID m_Selection = 0;
-    EntityID m_LastSelection = 0;
+    EntityID m_Selection = EntityID_Invalid;
+    EntityID m_LastSelection = EntityID_Invalid;
+    EntityID m_UIDraggingEntity = EntityID_Invalid;
     glm::vec3 m_Position;
+    std::string m_LastDroppedFile;
+
+    static boost::filesystem::path openDialog(boost::filesystem::path defaultPath);
+    static boost::filesystem::path saveDialog(boost::filesystem::path defaultPath);
 
     EventRelay<EditorSystem, Events::InputCommand> m_EInputCommand;
     bool OnInputCommand(const Events::InputCommand& e);
@@ -58,13 +74,19 @@ private:
     bool OnMousePress(const Events::MousePress& e);
     EventRelay<EditorSystem, Events::MouseMove> m_EMouseMove;
     bool OnMouseMove(const Events::MouseMove& e);
-
+    EventRelay<EditorSystem, Events::FileDropped> m_EFileDropped;
+    bool OnFileDropped(const Events::FileDropped& e);
+    
     void Picking();
-
+    void createWidget();
     void updateWidget();
     void setWidgetMode(WidgetMode newMode);
     void setWidgetSpace(WidgetSpace space);
     void drawUI(World* world, double dt);
     bool createDeleteButton(std::string componentType);
+    bool createEntityNode(World* world, EntityID entity);
     void changeParent(EntityID entity, EntityID newParent);
+    void fileImport(World* world);
+    void fileSave(World* world);
+    void fileSaveAs(World* world);
 };

include/Engine/Network/Client.h

@@ -1,14 +1,84 @@
 #ifndef Client_h__
 #define Client_h__
 
-#include <boost\asio.hpp>
+#include <string>
+#include <ctime>
 
-class Client
+#include <glm/common.hpp>
+#include <boost/asio.hpp>
+
+#include "Network/Network.h"
+#include "Network/MessageType.h"
+#include "Network/PlayerDefinition.h"
+#include "Network/SnapshotDefinitions.h"
+#include "Core/World.h"
+#include "Core/EventBroker.h"
+#include "Core/ConfigFile.h"
+#include "Input/EInputCommand.h"
+
+class Client : public Network
 {
-	Client();
-	~Client();
+public:
+    Client(ConfigFile* config);
+    ~Client();
+    void Start(World* world, EventBroker* eventBroker) override;
+    void Update() override;
+    void Close();
+private:
+    // Assio UDP logic
+    boost::asio::ip::udp::endpoint m_ReceiverEndpoint;
+    boost::asio::io_service m_IOService;
+    boost::asio::ip::udp::socket m_Socket;
 
+    // Sending message to server logic
+    int bytesRead = -1;
+    char readBuf[1024] = { 0 };
+    int snapshotInterval = 33;
+    std::clock_t previousSnapshotMessage = std::clock();
 
+    // Packet loss logic
+    unsigned int m_PacketID = 0;
+    unsigned int m_PreviousPacketID = 0;
+    unsigned int m_SendPacketID = 0;
+
+    // Game logic
+    World* m_World;
+    std::string m_PlayerName;
+    int m_PlayerID = -1;
+
+    // Network logic
+    PlayerDefinition m_PlayerDefinitions[MAXCONNECTIONS];
+    SnapshotDefinitions m_NextSnapshot;
+    bool m_ThreadIsRunning = true;
+    double m_DurationOfPingTime;
+    std::clock_t m_StartPingTime;
+    // Use to check if we should send disconnect message
+    // if game is turned of by closing window.
+    bool m_WasStarted = false;
+
+    // Private member functions
+    void readFromServer();
+    void sendSnapshotToServer();
+    int receive(char* data, size_t length);
+    void send(Packet& packet);
+    void connect();
+    void disconnect();
+    void ping();
+    void moveMessageHead(char*& data, size_t& length, size_t stepSize);
+    void parseMessageType(Packet& packet);
+    void parseEventMessage(Packet& packet);
+    void parseConnect(Packet& packet);
+    void parsePing();
+    void parseServerPing();
+    void parseSnapshot(Packet& packet);
+    void identifyPacketLoss();
+    bool isConnected();
+    EntityID createPlayer();
+
+    // Events
+    EventBroker* m_EventBroker;
+    EventRelay<Client, Events::InputCommand> m_EInputCommand;
+    bool OnInputCommand(const Events::InputCommand &e);
 };
 
 #endif

include/Engine/Network/MessageType.h

@@ -0,0 +1,17 @@
+#ifndef MessageType_h__
+#define MessageType_h__
+
+// Message types used by both server and client.
+// Used to determine what type of message was sent.
+enum class MessageType
+{
+	Connect,
+	Disconnect,
+	ClientPing,
+	ServerPing,
+	Message,
+	Snapshot,
+	Event,
+};
+
+#endif

include/Engine/Network/Network.h

@@ -0,0 +1,19 @@
+#ifndef Network_h__
+#define Network_h__
+
+#include "Core/World.h"
+#include "Core/EventBroker.h"
+#include "Network/Packet.h"
+
+#define MAXCONNECTIONS 8
+#define INPUTSIZE 128
+
+class Network
+{
+public:
+    virtual ~Network() { };
+    virtual void Start(World* m_world, EventBroker *eventBroker) = 0;
+    virtual void Update() = 0;
+};
+
+#endif

include/Engine/Network/Packet.h

@@ -0,0 +1,61 @@
+#ifndef Packet_h__
+#define Packet_h__
+
+#include <string>
+#include "Network/MessageType.h"
+#include "Core/Util/Logging.h"
+
+// Defines the 
+class Packet
+{
+public:
+    // arg1: Type of message (Connect, Disconnect...)
+    // arg2: PacketID for identifying packet loss.
+    Packet(MessageType type, unsigned int& packetID);
+    // Used to create packet from already existing data buffer.
+    Packet(char* data, const int sizeOfPacket);
+    
+    ~Packet();
+    // Add primitive types like int, float, char...
+    template<typename T>
+    void WritePrimitive(T val)
+    {
+        // Check if we are trying to add more than the package can fit.
+        if (m_MaxPacketSize < m_Offset + sizeof(T)) {
+            LOG_WARNING("Packet AddPrimitive(): You are trying to add more than we have allocated for!");
+        }
+        memcpy(m_Data + m_Offset, &val, sizeof(T));
+        m_Offset += sizeof(T);
+    }
+    // Pops the first element as if it was a primitive.
+    template<typename T>
+    T ReadPrimitive()
+    {
+        if (m_Offset < m_ReturnDataOffset + sizeof(T)) {
+            LOG_WARNING("Packet PopFrontPrimitive(): You are trying to remove more than what exists in this packet!");
+            return -1;
+        }
+        T returnValue;
+        memcpy(&returnValue, m_Data + m_ReturnDataOffset, sizeof(T));
+        m_ReturnDataOffset += sizeof(T);
+        return returnValue;
+    }
+    // Add a string to the message
+    void WriteString(std::string str);
+    // Add data to the message
+    void WriteData(char* data, int sizeOfData);
+    // Pops the first element as if it was a string.
+    std::string ReadString();
+    char* ReadData(int SizeOfData);
+
+    int Size() { return m_Offset; };
+    char* Data() { return m_Data; };
+
+private:
+    char* m_Data;
+    unsigned int m_ReturnDataOffset = 0;
+    int m_Offset = 0;
+    unsigned int m_MaxPacketSize = 128;
+};
+
+#endif

include/Engine/Network/PlayerDefinition.h

@@ -0,0 +1,11 @@
+#ifndef PlayerDefinition_h__
+#define PlayerDefinition_h__
+#include <string>
+
+struct PlayerDefinition {
+    int EntityID = -1;
+    std::string Name = "";
+    boost::asio::ip::udp::endpoint Endpoint;
+};
+
+#endif

include/Engine/Network/Server.h

@@ -1,12 +1,85 @@
 #ifndef Server_h__
 #define Server_h__
 
-#include <boost\asio.hpp>
+#include <string>
+#include <ctime>
 
-class Server
+#include <glm/common.hpp>
+#include <boost/asio/ip/udp.hpp>
+
+#include "Network/MessageType.h"
+#include "Network/PlayerDefinition.h"
+#include "Core/World.h"
+#include "Core/EventBroker.h"
+#include "Network/Network.h"
+
+class Server : public Network
 {
-	Server();
-	~Server();
+public:
+    Server();
+    ~Server();
+    void Start(World* m_world, EventBroker *eventBroker) override;
+    void Update() override;
+    void Close();
+
+private:
+    // UDP logic
+    boost::asio::ip::udp::endpoint m_ReceiverEndpoint;
+    boost::asio::io_service m_IOService;
+    boost::asio::ip::udp::socket m_Socket;
+    PlayerDefinition m_PlayerDefinitions[MAXCONNECTIONS];
+
+    // Sending messages to client logic
+    char readBuffer[1024] = { 0 };
+    int bytesRead = 0;
+    // time for previouse message
+    std::clock_t previousePingMessage = std::clock();
+    std::clock_t previousSnapshotMessage = std::clock();
+    std::clock_t timOutTimer = std::clock();
+    // How often we send messages (milliseconds)
+    int intervalMs = 1000;
+    int snapshotInterval = 50;
+    int checkTimeOutInterval = 100;
+
+    //Timers
+    std::clock_t m_StartPingTime;
+    std::clock_t m_StopTimes[8];
+
+    // Game logic
+    World* m_World;
+    EventBroker* m_EventBroker;
+    // vec.size() = ammount of players to create, stores playerID's
+    std::vector<unsigned int> m_PlayersToCreate;
+    
+    // Packet loss logic
+    unsigned int m_PacketID;
+    unsigned int m_PreviousPacketID;
+    unsigned int m_SendPacketID;
+    
+    // Close logic
+    bool m_ThreadIsRunning = true;
+
+    // Private member functions
+    int  receive(char* data, size_t length);
+    void readFromClients();
+    void send(Packet& packet, int playerID);
+    void send(Packet& packet);
+    void moveMessageHead(char*& data, size_t& length, size_t stepSize);
+    void broadcast(std::string message);
+    void broadcast(Packet& packet);
+    void sendSnapshot();
+    void sendPing();
+    void checkForTimeOuts();
+    void disconnect(int i);
+    void parseMessageType(Packet& packet);
+    void parseEvent(Packet& packet);
+    void parseConnect(Packet& packet);
+    void parseDisconnect();
+    void parseClientPing();
+    void parseServerPing();
+    void parseSnapshot(Packet& packet);
+    void identifyPacketLoss();
+    EntityID createPlayer();
 };
 
 #endif

include/Engine/Network/SnapshotDefinitions.h

@@ -0,0 +1,12 @@
+#ifndef SnapshotDefinitions_h__
+#define SnapshotDefinitions_h__
+
+struct SnapshotDefinitions
+{
+	// "+Forward" is 8 characters * sizeof(char) = 8
+	std::string InputForward;
+	// "+Right" is 6 characters * sizeof(char) = 6
+    std::string InputRight;
+};
+
+#endif

include/Engine/Rendering/IRenderer.h

@@ -42,7 +42,7 @@ public:
     virtual PickData Pick(glm::vec2 screenCord) = 0;
 
 protected:
-	Rectangle m_Resolution = Rectangle(1280, 720);
+	Rectangle m_Resolution = Rectangle::Rectangle(1280, 720);
 	bool m_Fullscreen = false;
 	bool m_VSYNC = false;
 	int m_GLVersion[2];

include/Engine/Rendering/RenderSystem.h

@@ -18,7 +18,7 @@ class RenderSystem : public ImpureSystem
 {
 public:
     RenderSystem(EventBroker* eventBrokerer, const IRenderer* renderer, RenderFrame* renderFrame);
-    
+
     virtual void Update(World* world, double dt) override;
 
     static glm::vec3 AbsolutePosition(World* world, EntityID entity);
@@ -40,7 +40,7 @@ private:
 
     EventRelay<RenderSystem, Events::SetCamera> m_ESetCamera;
     bool OnSetCamera(const Events::SetCamera &event);
-    EntityID m_CurrentCamera = -1;
+    EntityID m_CurrentCamera = EntityID_Invalid;
 
     void switchCamera(EntityID entity);
 
@@ -50,8 +50,8 @@ private:
     glm::mat4 m_ViewMatrix;
     glm::mat4 m_ProjectionMatrix;
     
-    glm::mat4 ModelMatrix(EntityID entity);
-    void fillModels(std::list<std::shared_ptr<RenderJob>>& jobs);
+    glm::mat4 ModelMatrix(EntityID entity, World* world);
+    void fillModels(std::list<std::shared_ptr<RenderJob>>& jobs, World* world);
 
     EventRelay<RenderSystem, Events::InputCommand> m_EInputCommand;
     bool OnInputCommand(const Events::InputCommand& e);