Rework some stuff for memory

examples/snake/src/main.cpp

@@ -14,7 +14,7 @@
 
 class SnakeMovementComponent : public simpleengine::Component {
 public:
-    explicit SnakeMovementComponent(simpleengine::Entity* owning_entity, float movement_speed) : simpleengine::Component(owning_entity), movement_speed(movement_speed) {
+    explicit SnakeMovementComponent(simpleengine::Entity& owning_entity, float movement_speed) : simpleengine::Component(owning_entity), movement_speed(movement_speed) {
 
     }
 
@@ -39,7 +39,7 @@ public:
             movement_direction.y = 1;
         }
 
-        owning_entity->Move(delta_time, movement_direction.x, movement_direction.y);
+        owning_entity.Move(delta_time, movement_direction.x, movement_direction.y);
     }
 private:
     float movement_speed;
@@ -57,7 +57,7 @@ public:
         shape = sf::RectangleShape(sf::Vector2f(15, 15));
         shape.setFillColor(sf::Color::White);
 
-        this->AddComponent(new SnakeMovementComponent(this, movement_speed));
+        this->AddComponent(std::make_unique<SnakeMovementComponent>(*this, movement_speed));
         loc = sf::Vector2f(0, 0);
     }
 
@@ -69,11 +69,11 @@ public:
         UpdateComponents(delta_time);
 
         if (loc.x >= window_size.x) {
-            DestroyEntity();
+            DestroyLater();
         }
 
         if (loc.y >= window_size.y) {
-            DestroyEntity();
+            DestroyLater();
         }
     }
 
@@ -84,7 +84,7 @@ public:
 
 int main(int argc, char *argv[]) {
     simpleengine::Game game(500, 500, "First Example");
-    game.AddEvent(new simpleengine::EntityEvent(game.GetWindow(), new SnakePlayerEntity(game.GetWindow()->getSize())));
+    game.AddEvent(new simpleengine::EntityEvent(game.GetWindow(), std::make_unique<SnakePlayerEntity>(game.GetWindow()->getSize())));
 
     return game.Run();
 }

include/simpleengine/component.h

@@ -9,17 +9,24 @@
 
 #include <SFML/Graphics.hpp>
 
+#include <memory>
+
 namespace simpleengine {
     class Entity;
     class Component {
     public:
-        explicit Component(Entity* owning_entity = nullptr) : owning_entity(owning_entity) {}
-        virtual ~Component() = default;
+        explicit Component(Entity& owning_entity);
+        //virtual ~Component() = default;
+
+        //virtual void Destroying(); // Called when the Component is about to be destroyed.
+        void DestroyLater(); // In most cases, this will be ran next Entity::Update.
+        const bool& IsGettingDestroyed() const;
 
         virtual void Update(const float& delta_time) = 0;
         virtual void Render(sf::RenderTarget* target) {}; // Most components won't need to be rendered.
     protected:
-        Entity* owning_entity;
+        Entity& owning_entity;
+        bool destroying = false;
     };
 }
 

include/simpleengine/components/movement/movement_component.h

@@ -16,7 +16,7 @@ namespace simpleengine {
 
     class MovementComponent : public Component {
     public:
-        explicit MovementComponent(Entity* owning_entity, float movement_speed);
+        MovementComponent(Entity& owning_entity, float movement_speed);
 
         void Update(const float &delta_time) override;
     private:

include/simpleengine/entity.h

@@ -9,43 +9,48 @@
 
 #include <SFML/Graphics.hpp>
 
-#include <stack>
+#include <vector>
+#include <memory>
 
 namespace simpleengine {
     class Component;
     class Game;
     class Event;
-    class Entity {
+
+    class Entity : std::enable_shared_from_this<Entity> {
         friend class Game;
         friend class Event;
     public:
         Entity() = default;
         virtual ~Entity() = default;
+        Entity(const Entity& entity) = delete;
 
         virtual void Move(const float& delta_time, const float& x, const float& y) {};
         virtual void Update(const float& delta_time) = 0;
         virtual void Render(sf::RenderTarget* target) = 0;
-        virtual void Destroying() {}; // Called when the entity is about to be destroyed.
 
-        void DestroyEntity() {
-            destroying = true;
-        }
+        // Called when the entity is about to be destroyed.
+        // Make sure to call this in your extending Entity.
+        virtual void Destroying();
 
-        const bool& IsGettingDestroyed() const {
-            return destroying;
-        }
+        void DestroyLater(); // In most cases, this will be ran next EntityEvent::Update()
+        const bool& IsGettingDestroyed() const;
 
         // If your event does not extend from EntityEvent, you will need to execute this yourself inside Event::Update.
         void UpdateComponents(const float& delta_time);
 
-        void AddComponent(Component* component);
+        void AddComponent(std::unique_ptr<Component> component);
+
+        std::shared_ptr<Entity> GetShared() {
+            return shared_from_this();
+        }
     private:
         // This is ran from class `Game` and `Event`. It runs the `UpdateComponents` method and then the `Update` method.
         void UpdateEntity(const float& delta_time) {
             UpdateComponents(delta_time);
         }
 
-        std::vector<Component*> components;
+        std::vector<std::unique_ptr<Component>> components;
         bool destroying = false;
     };
 }

include/simpleengine/events/entity_event.h

@@ -13,14 +13,10 @@
 namespace simpleengine {
     class EntityEvent : public Event {
     public:
-        explicit EntityEvent(sf::RenderWindow* window, Entity* entity) : simpleengine::Event(window), entity(entity) {
+        explicit EntityEvent(sf::RenderWindow* window, std::unique_ptr<Entity> entity) : simpleengine::Event(window), entity(std::move(entity)) {
 
         }
 
-        ~EntityEvent() override {
-            delete entity;
-        }
-
         void CheckForQuit() override {
             /*if (sf::Keyboard::isKeyPressed(sf::Keyboard::Escape)) {
                 quit = true;
@@ -29,13 +25,17 @@ namespace simpleengine {
 
         void Update(const float& delta_time) override {
             entity->Update(delta_time);
+
+            if (entity->IsGettingDestroyed()) {
+                entity->DestroyLater();
+            }
         }
 
         void Render(sf::RenderTarget* target) override {
             entity->Render(target);
         }
     private:
-        Entity* entity;
+        std::unique_ptr<Entity> entity;
     };
 }
 

include/simpleengine/game.h

@@ -12,6 +12,8 @@
 #include <SFML/Audio.hpp>
 
 #include <stack>
+#include "entity.h"
+
 
 namespace simpleengine {
     class Event;

src/component.cpp

@@ -0,0 +1,19 @@
+//
+// Created by SeanOMik on 7/3/2020.
+// Github: https://github.com/SeanOMik
+// Email: seanomik@gmail.com
+//
+
+#include "component.h"
+
+simpleengine::Component::Component(Entity& owning_entity) : owning_entity(owning_entity) {
+
+}
+
+void simpleengine::Component::DestroyLater() {
+    destroying = true;
+}
+
+const bool &simpleengine::Component::IsGettingDestroyed() const {
+    return destroying;
+}

src/components/movement/movement_component.cpp

@@ -5,27 +5,29 @@
 //
 
 #include "components/movement/movement_component.h"
+
+#include <utility>
 #include "entity.h"
 
-simpleengine::MovementComponent::MovementComponent(simpleengine::Entity *owning_entity, float movement_speed) :
+simpleengine::MovementComponent::MovementComponent(Entity& owning_entity, float movement_speed) :
     Component(owning_entity), movement_speed(movement_speed) {
 
 }
 
 void simpleengine::MovementComponent::Update(const float &delta_time) {
     if (sf::Keyboard::isKeyPressed(sf::Keyboard::A)) {
-        owning_entity->Move(delta_time, -1, 0);
+        owning_entity.Move(delta_time, -1, 0);
     }
 
     if (sf::Keyboard::isKeyPressed(sf::Keyboard::W)) {
-        owning_entity->Move(delta_time, 0, -1);
+        owning_entity.Move(delta_time, 0, -1);
     }
 
     if (sf::Keyboard::isKeyPressed(sf::Keyboard::D)) {
-        owning_entity->Move(delta_time, 1, 0);
+        owning_entity.Move(delta_time, 1, 0);
     }
 
     if (sf::Keyboard::isKeyPressed(sf::Keyboard::S)) {
-        owning_entity->Move(delta_time, 0, 1);
+        owning_entity.Move(delta_time, 0, 1);
     }
 }

src/entity.cpp

@@ -8,11 +8,29 @@
 #include "component.h"
 
 void simpleengine::Entity::UpdateComponents(const float& delta_time) {
-    for (Component* component : components) {
+    for (std::unique_ptr<Component>& component : components) {
         component->Update(delta_time);
+
+        if (component->IsGettingDestroyed()) {
+            components.erase(std::remove(components.begin(), components.end(), component));
+        }
     }
 }
 
-void simpleengine::Entity::AddComponent(simpleengine::Component *component) {
-    components.emplace_back(component);
+void simpleengine::Entity::AddComponent(std::unique_ptr<Component> component) {
+    components.push_back(std::move(component));
+}
+
+void simpleengine::Entity::Destroying() {
+    for (std::unique_ptr<Component>& component : components) {
+        component->DestroyLater();
+    }
+}
+
+void simpleengine::Entity::DestroyLater() {
+    destroying = true;
+}
+
+const bool &simpleengine::Entity::IsGettingDestroyed() const {
+    return destroying;
 }