Refactor & More.

Changed the entity system to utilize mix-ins.

Added instanced sprites.

Texture support.

include/Engine/Entity/Camera.h

@@ -1,13 +0,0 @@
-#pragma once
-#include <Engine/Entity/Renderable.h>
-
-namespace Engine {
-    class Camera;
-}
-
-class Engine::Camera : public Renderable {
-public:
-    void Render() override {};
-public:
-    explicit Camera(const Vector2& position) : Renderable(position, 0) {}
-};

include/Engine/Entity/Entity.h

@@ -1,59 +0,0 @@
-#pragma once
-#include <J3ML/LinearAlgebra/Vector2.hpp>
-#include <vector>
-#include <chrono>
-
-namespace Engine {
-    class Entity;
-}
-
-class Engine::Entity {
-protected:
-    // nullptr means no parent.
-    Entity* parent = nullptr;
-
-    // Epoch micro-seconds.
-    long creation_time = 0.0f;
-    std::vector<Entity*> children{};
-    Vector2 position = {0, 0};
-    // Assuming 0 radians is up.
-    float face_angle = 0.0f;
-    void UpdateChildren();
-public:
-    // Movements independent of the face_angle.
-    void MoveX(float speed);
-    void MoveY(float speed);
-    void Move(float angle_rad, float speed);
-
-    // Movements dependent on face angle.
-    void MoveForward(float speed);
-    void MoveBackward(float speed);
-    void MoveLeft(float speed);
-    void MoveRight(float speed);
-
-    void Rotate(float speed);
-    void SetRotation(float new_rotation);
-
-    // Parent child structure.
-    [[nodiscard]] bool AppendChild(Entity* entity);
-    void DestroyChild(Entity* entity);
-    void RemoveChild(Entity* entity);
-public:
-    [[nodiscard]] std::vector<Entity*> GetChildren() const;
-    [[nodiscard]] Entity* GetParent() const;
-
-    // Microseconds.
-    [[nodiscard]] long GetCreationTime() const;
-    [[nodiscard]] long GetAge() const;
-
-    [[nodiscard]] float GetRotation() const;
-    [[nodiscard]] Vector2 GetPosition() const;
-
-public:
-    virtual void Update() {}
-public:
-    virtual ~Entity();
-    explicit Entity(const Vector2& position, float rotation = 0.0f) :
-    creation_time(std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count()),
-    position(position), face_angle(rotation) {}
-};

include/Engine/Entity/Renderable.h

@@ -1,22 +0,0 @@
-#pragma once
-
-#include <Engine/Entity/Entity.h>
-#include <JGL/JGL.h>
-
-namespace Engine {
-    class Renderable;
-}
-
-class Engine::Renderable : public Entity {
-protected:
-    // Higher numbers are farther to the back.
-    unsigned int depth = 0;
-public:
-    [[nodiscard]] unsigned int GetDepth() const { return depth; }
-    void SetDepth(unsigned int new_depth) { depth = new_depth; }
-public:
-    // *must* be overridden.
-    virtual void Render() = 0;
-public:
-    explicit Renderable(const Vector2& position, unsigned int depth = 0, float rotation = 0.0f) : Entity(position, rotation), depth(depth) {}
-};

include/Engine/GameWindow.h

@@ -1,5 +1,6 @@
-#include <rewindow/types/window.h>
 #pragma once
+#include <rewindow/types/window.h>
+#include <rewindow/logger/logger.h>
 
 namespace Engine {
     class DemoGameWindow;
@@ -11,7 +12,16 @@ public:
 public:
     void OnRefresh(float elapsed) override;
 public:
-    DemoGameWindow() : ReWindow::RWindow() {}
-    DemoGameWindow(const std::string& title, int width, int height) : ReWindow::RWindow(title, width, height) {}
+    DemoGameWindow(const std::string& title, int width, int height) : ReWindow::RWindow(title, width, height)
+    {
+        ReWindow::Logger::Error.EnableConsole(false);
+        ReWindow::Logger::Warning.EnableConsole(false);
+        ReWindow::Logger::Debug.EnableConsole(false);
+        SetRenderer(RenderingAPI::OPENGL);
+        Open();
+        InitGL();
+        SetResizable(false);
+        SetVsyncEnabled(false);
+    }
 
 };

include/Engine/Globals.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#include <Engine/Level/Scene.h>
+#include <Engine/types/scene/Scene.h>
 #include <Engine/GameWindow.h>
 
 namespace Globals {

include/Engine/types/InstancedTexture.h

@@ -0,0 +1,24 @@
+#pragma once
+#include <vector>
+#include <JGL/types/Texture.h>
+
+namespace Engine {
+    class InstancedTexture;
+    class InstancedSprite;
+}
+
+class Engine::InstancedTexture {
+protected:
+    JGL::Texture* texture;
+    std::vector<const InstancedSprite*> users{};
+public:
+    [[nodiscard]] size_t ReferenceCount() { return users.size(); }
+    [[nodiscard]] bool InUseBy(const InstancedSprite* rhs);
+    [[nodiscard]] JGL::Texture* GetTexture() const { return texture; }
+public:
+    void AddUser(const InstancedSprite* user);
+    void RemoveUser(const InstancedSprite* user);
+public:
+    InstancedTexture(JGL::Texture* texture, const InstancedSprite* creator) : texture(texture) { users.push_back(creator); }
+    ~InstancedTexture();
+};

include/Engine/types/entity/Camera.h

@@ -0,0 +1,15 @@
+#pragma once
+#include <Engine/types/entity/Entity.h>
+#include <Engine/types/entity/mixins/Movable.h>
+#include <Engine/types/entity/mixins/Renderable.h>
+
+namespace Engine {
+    class Camera;
+}
+
+class Engine::Camera : public Entity, public Movable, public Renderable {
+public:
+    void Render() override {};
+public:
+    explicit Camera(const Vector2& position) : Renderable(0), Movable(position) {}
+};

include/Engine/types/entity/Entity.h

@@ -0,0 +1,36 @@
+#pragma once
+#include <J3ML/LinearAlgebra/Vector2.hpp>
+#include <vector>
+#include <chrono>
+
+namespace Engine {
+    class Entity;
+}
+
+class Engine::Entity {
+protected:
+    // nullptr means no parent.
+    Entity* parent = nullptr;
+
+    // Epoch micro-seconds.
+    long creation_time = 0.0f;
+    std::vector<Entity*> children{};
+    void UpdateChildren();
+public:
+    // Parent child structure.
+    [[nodiscard]] bool AppendChild(Entity* entity);
+    void DestroyChild(Entity* entity);
+    void RemoveChild(Entity* entity);
+public:
+    [[nodiscard]] std::vector<Entity*> GetChildren() const;
+    [[nodiscard]] Entity* GetParent() const;
+
+    // Microseconds.
+    [[nodiscard]] long GetCreationTime() const;
+    [[nodiscard]] long GetAge() const;
+public:
+    virtual void Update() {}
+public:
+    virtual ~Entity();
+    explicit Entity() : creation_time(std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count()) {}
+};

include/Engine/types/entity/Hud.h

@@ -1,5 +1,5 @@
 #pragma once
-#include <Engine/Entity/Renderable.h>
+#include <Engine/types/entity/mixins/Renderable.h>
 
 namespace Engine {
     class Hud;
@@ -7,5 +7,5 @@ namespace Engine {
 
 class Engine::Hud : public Engine::Renderable {
 public:
-    Hud() : Renderable({0, 0}, 0, 0) {};
+    Hud() : Renderable(0) {};
 };

include/Engine/types/entity/InstancedSprite.h

@@ -0,0 +1,28 @@
+#pragma once
+#include <Engine/types/entity/Sprite.h>
+
+namespace Engine {
+    class InstancedSprite;
+}
+
+class Engine::InstancedSprite : public Sprite {
+private:
+    std::string texture_path;
+    std::string alpha_mask_path;
+public:
+    [[nodiscard]] std::string GetTextureFilesystemPath() const { return texture_path; }
+    [[nodiscard]] std::string GetAlphaMaskFilesystemPath() const { return alpha_mask_path; }
+    [[nodiscard]] Texture* GetTexture() override;
+    [[nodiscard]] Texture* GetAlphaMask() override;
+public:
+    /** The Texture *must* be instanced. The alpha-mask *can* be instanced.
+     * You can use SetAlphaMask() to change to a unique one.
+     * To change back to the instanced one if there is one, You can SetAlphaMask(nullptr);
+     * If there is no instanced alpha mask and unique alpha mask is set
+     * to nullptr, Then there is no alpha mask. - Redacted.
+    */
+    InstancedSprite(const Vector2& position, unsigned int layer, const std::string& instanced_texture_filesystem_path,
+                    float face_angle = 0.0f, const Color4& base_color = Colors::White, Texture* unique_alpha_mask = nullptr, const std::string& instanced_alpha_mask_filesystem_path = "")
+                    : texture_path(instanced_texture_filesystem_path), alpha_mask_path(instanced_alpha_mask_filesystem_path),
+                    Sprite(position, layer, face_angle, base_color, nullptr, unique_alpha_mask) {}
+};

include/Engine/types/entity/Sprite.h

@@ -1,6 +1,9 @@
 #pragma once
 
-#include <Engine/Entity/Renderable.h>
+#include <Colors.hpp>
+#include <Engine/types/entity/Entity.h>
+#include <Engine/types/entity/mixins/Movable.h>
+#include <Engine/types/entity/mixins/Renderable.h>
 #include <JGL/types/Texture.h>
 #include <J3ML/Geometry/AABB2D.hpp>
 
@@ -8,23 +11,24 @@ namespace Engine {
     class Sprite;
 }
 
-class Engine::Sprite : public Renderable {
-protected:
+using JGL::Texture;
+class Engine::Sprite : public Entity, public Renderable, public Movable {
+private:
     Texture* texture = nullptr;
-    // Positive alpha mask.
     Texture* alpha_mask = nullptr;
+protected:
     Vector2 scale = {1, 1};
     // Local space, Where the face_angle rotation should be preformed about.
     Vector2 origin = {0, 0};
     Color4 base_color = Colors::White;
-public:
-    [[nodiscard]] Texture* GetTexture();
-    // World space.
-    [[nodiscard]] virtual AABB2D GetBounds();
+protected:
+    [[nodiscard]] virtual Texture* GetTexture();
+    [[nodiscard]] virtual Texture* GetAlphaMask();
+    void SetAlphaMask(Texture* new_alpha_mask);
 public:
     void Render() override;
 public:
     ~Sprite() override;
-    explicit Sprite(const Vector2& pos, unsigned int depth = 0, const float face_angle = 0.0f, const Color4& base_color = Colors::White, Texture* texture = nullptr,
-                    Texture* alpha_mask = nullptr) : Renderable(pos, depth,face_angle), texture(texture), alpha_mask(alpha_mask), base_color(base_color) {}
+    explicit Sprite(const Vector2& pos, unsigned int layer = 0, const float face_angle = 0.0f, const Color4& base_color = Colors::White, Texture* texture = nullptr,
+                    Texture* alpha_mask = nullptr) : Renderable(layer), Movable(pos, face_angle), texture(texture), alpha_mask(alpha_mask), base_color(base_color) {}
 };

include/Engine/types/entity/mixins/BoxCollider.h

@@ -0,0 +1,20 @@
+#pragma once
+#include <J3ML/Geometry/AABB2D.hpp>
+
+namespace Engine {
+    class BoxCollider;
+}
+
+class Engine::BoxCollider {
+private:
+    bool enabled = false;
+public:
+    [[nodiscard]] virtual AABB2D GetBounds() = 0;
+    [[nodiscard]] bool BoxCollides(BoxCollider* rhs);
+    [[nodiscard]] bool BoxCollides(const Vector2& rhs);
+public:
+    void EnableBoxCollision() { enabled = true; }
+    void DisableBoxCollision() { enabled = false; }
+public:
+    explicit BoxCollider(bool enabled = true) : enabled(enabled) {}
+};

include/Engine/types/entity/mixins/Movable.h

@@ -0,0 +1,34 @@
+#pragma once
+
+#include <J3ML/LinearAlgebra/Vector2.hpp>
+
+namespace Engine {
+    class Movable;
+}
+
+// Movable Object.
+class Engine::Movable {
+protected:
+    // Assuming 0 radians is up.
+    float face_angle = 0.0f;
+    Vector2 position = {0, 0};
+public:
+    // Movements independent of the face_angle.
+    void MoveX(float speed);
+    void MoveY(float speed);
+    void Move(float angle_rad, float speed);
+
+    // Movements dependent on face angle.
+    void MoveForward(float speed);
+    void MoveBackward(float speed);
+    void MoveLeft(float speed);
+    void MoveRight(float speed);
+
+    void Rotate(float speed);
+    void SetRotation(float new_rotation);
+public:
+    [[nodiscard]] float GetRotation() const;
+    [[nodiscard]] Vector2 GetPosition() const;
+public:
+    explicit Movable(const Vector2& position, float rad_rotation = 0.0f) : position(position), face_angle(rad_rotation) {}
+};

include/Engine/types/entity/mixins/Renderable.h

@@ -0,0 +1,20 @@
+#pragma once
+#include <Engine/types/entity/Entity.h>
+
+namespace Engine {
+    class Renderable;
+}
+
+class Engine::Renderable {
+protected:
+    // Higher numbers are farther to the back.
+    unsigned int layer = 0;
+public:
+    [[nodiscard]] unsigned int GetLayer() const { return layer; }
+    void SetLayer(unsigned int new_layer) { layer = new_layer; }
+public:
+    // *must* be overridden.
+    virtual void Render() = 0;
+public:
+    explicit Renderable(unsigned int layer) :  layer(layer) {}
+};

include/Engine/types/scene/Fixed.h

@@ -1,8 +1,8 @@
 #pragma once
 
-#include "J3ML/LinearAlgebra/Vector2i.hpp"
-#include "J3ML/Geometry/AABB2D.hpp"
-#include "JGL/types/Texture.h"
+#include <J3ML/LinearAlgebra/Vector2i.hpp>
+#include <J3ML/Geometry/AABB2D.hpp>
+#include <JGL/types/Texture.h>
 
 using J3ML::LinearAlgebra::Vector2i;
 using JGL::Texture;

include/Engine/types/scene/Scene.h

@@ -1,9 +1,9 @@
 #pragma once
 
 #include <vector>
-#include <Engine/Entity/Renderable.h>
-#include <Engine/Entity/Hud.h>
-#include <Engine/Level/Fixed.h>
+#include <Engine/types/InstancedTexture.h>
+#include <Engine/types/entity/Hud.h>
+#include <Engine/types/scene/Fixed.h>
 #include <JGL/types/RenderTarget.h>
 
 namespace Engine {
@@ -11,11 +11,18 @@ namespace Engine {
     class Scene;
 }
 
+using namespace JGL;
+
 class Engine::Scene {
 protected:
     std::string name;
     Hud* heads_up_display = nullptr;
     Camera* active_camera = nullptr;
+
+    std::vector<InstancedTexture*> instanced_textures{};
+    std::vector<InstancedTexture*> instanced_alpha_masks{};
+
+    std::vector<RenderTarget*> layers{};
     std::vector<Fixed*> fixed_list{};
     std::vector<Entity*> entity_list{};
 protected:
@@ -27,6 +34,8 @@ public:
     [[nodiscard]] size_t EntityCount() const;
     [[nodiscard]] std::string GetName() const;
     [[nodiscard]] Camera* GetActiveCamera() const;
+    [[nodiscard]] Texture* GetInstancedTexture(const InstancedSprite* user);
+    [[nodiscard]] Texture* GetInstancedAlphaMask(const InstancedSprite* user);
 public:
     void AppendEntity(Entity* entity);
     void AppendFixed(Fixed* fixed);

include/Game/Entity/Box.h

@@ -1,16 +0,0 @@
-#pragma once
-
-#include <Engine/Entity/Renderable.h>
-#include <Engine/Globals.h>
-
-namespace Game {
-    class Box;
-}
-
-class Game::Box final : public Engine::Renderable {
-public:
-    void Render() final;
-    void Update() final;
-public:
-    explicit Box(const Vector2& position, unsigned int depth = 0, float rotation = 0.0f) : Renderable(position, depth, rotation) {}
-};

include/Game/entity/Box.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <Engine/types/entity/Entity.h>
+#include <Engine/types/entity/mixins/Movable.h>
+#include <Engine/types/entity/mixins/Renderable.h>
+
+namespace Game {
+    class Box;
+}
+
+class Game::Box final : public Engine::Entity, public Engine::Renderable, public Engine::Movable {
+public:
+    void Render() final;
+    void Update() final;
+public:
+    explicit Box(const Vector2& position, unsigned int depth = 0, float rotation = 0.0f) : Renderable(depth), Movable(position, rotation) {}
+};

include/Game/entity/DemoGameHud.h

@@ -1,4 +1,4 @@
-#include <Engine/Entity/Hud.h>
+#include <Engine/types/entity/Hud.h>
 
 namespace Game {
     class DemoGameHud;

include/Game/scene/ControllableBox.h

@@ -1,5 +1,5 @@
 #pragma once
-#include <Engine/Level/Scene.h>
+#include <Engine/types/scene/Scene.h>
 
 class ControllableBox final : public Engine::Scene {
 public:

include/Game/scene/Loading.h

@@ -1,5 +1,6 @@
 #pragma once
-#include <Engine/Level/Scene.h>
+#include <Engine/types/scene/Scene.h>
+#include <JGL/types/RenderTarget.h>
 
 class LoadingScreen final : public Engine::Scene {
 protected:
@@ -11,6 +12,6 @@ public:
 
     void Init() final;
     void Update() final;
-    void Render(RenderTarget* render_target =  nullptr) final;
+    void Render(JGL::RenderTarget* render_target =  nullptr) final;
     ~LoadingScreen() final;
 };

main.cpp

@@ -1,7 +1,6 @@
 #include <Engine/Globals.h>
-#include <rewindow/logger/logger.h>
-#include <Game/Scene/ControllableBox.h>
-#include <Game/Scene/Loading.h>
+#include <Game/scene/Loading.h>
+#include <Game/scene/ControllableBox.h>
 
 using namespace JGL;
 
@@ -14,16 +13,7 @@ void CreateScenes() {
 };
 
 int main() {
-    ReWindow::Logger::Error.EnableConsole(false);
-    ReWindow::Logger::Warning.EnableConsole(false);
-    ReWindow::Logger::Debug.EnableConsole(false);
-
     Globals::Window = new Engine::DemoGameWindow("Demo Game", 1024, 896);
-    Globals::Window->SetRenderer(RenderingAPI::OPENGL);
-    Globals::Window->Open();
-    Globals::Window->InitGL();
-    Globals::Window->SetResizable(false);
-    Globals::Window->SetVsyncEnabled(false);
 
     CreateScenes();
     Globals::ChangeScene("LoadingScreen");

src/Engine/Animation.cpp

@@ -1,5 +1,5 @@
-#include "Engine/Entity/Animation.h"
-#include "jlog/Logger.hpp"
+#include <Engine/types/entity/Animation.h>
+#include <jlog/Logger.hpp>
 
 float Animation::GetMsBetweenFrames() const {
     return ms_between_frames;

src/Engine/Entity/Entity.cpp

@@ -1,109 +0,0 @@
-#include <J3ML/J3ML.hpp>
-#include <Engine/Entity/Entity.h>
-#include <Engine/Globals.h>
-
-using namespace J3ML;
-void Engine::Entity::MoveX(float speed) {
-    position.x = position.x + (speed * Globals::Window->GetDeltaTime());
-}
-
-void Engine::Entity::MoveY(float speed) {
-    position.y = position.y + (speed * Globals::DeltaTime());
-}
-
-void Engine::Entity::Move(float angle_rad, float speed) {
-    position.x = position.x + (speed * Globals::DeltaTime()) * Math::Cos(angle_rad);
-    position.y = position.y + (speed * Globals::DeltaTime()) * Math::Sin(angle_rad);
-}
-
-void Engine::Entity::MoveForward(float speed) {
-    Move(face_angle, speed);
-}
-
-void Engine::Entity::MoveBackward(float speed) {
-    speed = -speed;
-    position.x = position.x + (speed * Globals::DeltaTime()) * Math::Cos(face_angle);
-    position.y = position.y + (speed * Globals::DeltaTime()) * Math::Sin(face_angle);
-}
-
-void Engine::Entity::MoveLeft(float speed) {
-    position.x = position.x + (speed * Globals::DeltaTime()) * -Math::Sin(face_angle);
-    position.y = position.y + (speed * Globals::DeltaTime()) * Math::Cos(face_angle);
-}
-
-void Engine::Entity::MoveRight(float speed) {
-    position.x = position.x + (speed * Globals::DeltaTime()) * Math::Sin(face_angle);
-    position.y = position.y + (speed * Globals::DeltaTime()) * -Math::Cos(face_angle);
-}
-
-void Engine::Entity::SetRotation(float new_face_angle) {
-    face_angle = new_face_angle;
-
-    if (face_angle < 0)
-        face_angle = fmod(face_angle + Math::Pi * 2, Math::Pi * 2);
-    else if (face_angle >= 2 * M_PI)
-        face_angle = fmod(face_angle, Math::Pi * 2);
-}
-
-void Engine::Entity::Rotate(float speed) {
-    SetRotation(face_angle + speed * Globals::DeltaTime());
-}
-
-float Engine::Entity::GetRotation() const {
-    return face_angle;
-}
-
-Vector2 Engine::Entity::GetPosition() const {
-    return position;
-}
-
-bool Engine::Entity::AppendChild(Entity* entity) {
-    bool success = false;
-    if (!Globals::CurrentScene->EntityListContains(entity)) {
-        entity->parent = this;
-        children.push_back(entity);
-        success = true;
-    }
-    return success;
-}
-
-Engine::Entity::~Entity() {
-    for (auto* e : children)
-        delete e;
-}
-
-void Engine::Entity::UpdateChildren() {
-    for (auto& e : children) {
-        e->Update();
-        if (!e->children.empty())
-            e->UpdateChildren();
-    }
-}
-
-void Engine::Entity::DestroyChild(Entity* entity) {
-    auto it = std::find(children.begin(), children.end(), entity);
-    if (it != children.end())
-        delete *it, children.erase(it);
-}
-
-void Engine::Entity::RemoveChild(Entity* entity) {
-    auto it = std::find(children.begin(), children.end(), entity);
-    if (it != children.end())
-        children.erase(it);
-}
-
-long Engine::Entity::GetCreationTime() const {
-    return creation_time;
-}
-
-long Engine::Entity::GetAge() const {
-    return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count() - creation_time;
-}
-
-Engine::Entity* Engine::Entity::GetParent() const {
-    return parent;
-}
-
-std::vector<Engine::Entity*> Engine::Entity::GetChildren() const {
-    return children;
-}

src/Engine/Entity/Sprite.cpp

@@ -1,21 +0,0 @@
-#include <Engine/Entity/Sprite.h>
-
-Engine::Sprite::~Sprite() {
-    delete texture;
-    delete alpha_mask;
-}
-
-void Engine::Sprite::Render() {
-    if (texture && !alpha_mask)
-        J2D::DrawSprite(texture, position, face_angle, origin, scale, base_color);
-    if (texture && alpha_mask)
-        J2D::DrawSprite(texture, alpha_mask, position, face_angle, origin, scale, base_color);
-}
-
-AABB2D Engine::Sprite::GetBounds() {
-    return { position, texture->GetDimensions() + position };
-}
-
-Texture* Engine::Sprite::GetTexture() {
-    return texture;
-}

src/Engine/GameWindow.cpp

@@ -1,6 +1,5 @@
 #include <Engine/GameWindow.h>
 #include <Engine/Globals.h>
-#include <Engine/Entity/Camera.h>
 #include <JGL/JGL.h>
 
 

src/Engine/types/InstancedTexture.cpp

@@ -0,0 +1,28 @@
+#include <Engine/types/InstancedTexture.h>
+#include <Engine/types/entity/InstancedSprite.h>
+
+using namespace Engine;
+void InstancedTexture::AddUser(const InstancedSprite* user) {
+    // Prevent double references.
+    if (!InUseBy(user))
+        users.push_back(user);
+}
+
+void InstancedTexture::RemoveUser(const InstancedSprite* user) {
+    auto it = std::find(users.begin(), users.end(), user);
+    if (it != users.end())
+        users.erase(it);
+}
+
+bool InstancedTexture::InUseBy(const InstancedSprite* rhs) {
+    for (const auto* u : users)
+        if (u == rhs)
+            return true;
+    return false;
+}
+
+InstancedTexture::~InstancedTexture() {
+    delete texture;
+    for (const auto* is: users)
+        delete is;
+}

src/Engine/types/entity/Entity.cpp

@@ -0,0 +1,53 @@
+#include <J3ML/J3ML.hpp>
+#include <Engine/types/entity/Entity.h>
+#include <Engine/Globals.h>
+
+bool Engine::Entity::AppendChild(Entity* entity) {
+    if (!Globals::CurrentScene->EntityListContains(entity)) {
+        entity->parent = this;
+        children.push_back(entity);
+        return true;
+    }
+    return false;
+}
+
+Engine::Entity::~Entity() {
+    for (auto* e : children)
+        delete e;
+}
+
+void Engine::Entity::UpdateChildren() {
+    for (auto& e : children) {
+        e->Update();
+        if (!e->children.empty())
+            e->UpdateChildren();
+    }
+}
+
+void Engine::Entity::DestroyChild(Entity* entity) {
+    auto it = std::find(children.begin(), children.end(), entity);
+    if (it != children.end())
+        delete *it, children.erase(it);
+}
+
+void Engine::Entity::RemoveChild(Entity* entity) {
+    auto it = std::find(children.begin(), children.end(), entity);
+    if (it != children.end())
+        children.erase(it);
+}
+
+long Engine::Entity::GetCreationTime() const {
+    return creation_time;
+}
+
+long Engine::Entity::GetAge() const {
+    return std::chrono::duration_cast<std::chrono::microseconds>(std::chrono::high_resolution_clock::now().time_since_epoch()).count() - creation_time;
+}
+
+Engine::Entity* Engine::Entity::GetParent() const {
+    return parent;
+}
+
+std::vector<Engine::Entity*> Engine::Entity::GetChildren() const {
+    return children;
+}

src/Engine/types/entity/InstancedSprite.cpp

@@ -0,0 +1,13 @@
+#include <Engine/types/entity/InstancedSprite.h>
+#include <Engine/Globals.h>
+
+using namespace Engine;
+Texture* InstancedSprite::GetTexture() {
+    return Globals::CurrentScene->GetInstancedTexture(this);
+}
+
+Texture* InstancedSprite::GetAlphaMask() {
+    if (Sprite::GetAlphaMask())
+        return Sprite::GetAlphaMask();
+    return Globals::CurrentScene->GetInstancedAlphaMask(this);
+}

src/Engine/types/entity/Moby.cpp

@@ -0,0 +1,57 @@
+#include "Engine/types/entity/mixins/Movable.h"
+#include "Engine/Globals.h"
+
+using namespace J3ML;
+void Engine::Movable::MoveX(float speed) {
+    position.x = position.x + (speed * Globals::Window->GetDeltaTime());
+}
+
+void Engine::Movable::MoveY(float speed) {
+    position.y = position.y + (speed * Globals::DeltaTime());
+}
+
+void Engine::Movable::Move(float angle_rad, float speed) {
+    position.x = position.x + (speed * Globals::DeltaTime()) * Math::Cos(angle_rad);
+    position.y = position.y + (speed * Globals::DeltaTime()) * Math::Sin(angle_rad);
+}
+
+void Engine::Movable::MoveForward(float speed) {
+    Move(face_angle, speed);
+}
+
+void Engine::Movable::MoveBackward(float speed) {
+    speed = -speed;
+    position.x = position.x + (speed * Globals::DeltaTime()) * Math::Cos(face_angle);
+    position.y = position.y + (speed * Globals::DeltaTime()) * Math::Sin(face_angle);
+}
+
+void Engine::Movable::MoveLeft(float speed) {
+    position.x = position.x + (speed * Globals::DeltaTime()) * -Math::Sin(face_angle);
+    position.y = position.y + (speed * Globals::DeltaTime()) * Math::Cos(face_angle);
+}
+
+void Engine::Movable::MoveRight(float speed) {
+    position.x = position.x + (speed * Globals::DeltaTime()) * Math::Sin(face_angle);
+    position.y = position.y + (speed * Globals::DeltaTime()) * -Math::Cos(face_angle);
+}
+
+void Engine::Movable::SetRotation(float new_face_angle) {
+    face_angle = new_face_angle;
+
+    if (face_angle < 0)
+        face_angle = fmod(face_angle + Math::Pi * 2, Math::Pi * 2);
+    else if (face_angle >= 2 * M_PI)
+        face_angle = fmod(face_angle, Math::Pi * 2);
+}
+
+void Engine::Movable::Rotate(float speed) {
+    SetRotation(face_angle + speed * Globals::DeltaTime());
+}
+
+float Engine::Movable::GetRotation() const {
+    return face_angle;
+}
+
+Vector2 Engine::Movable::GetPosition() const {
+    return position;
+}

src/Engine/types/entity/Sprite.cpp

@@ -0,0 +1,29 @@
+#include <Engine/types/entity/Sprite.h>
+#include <JGL/JGL.h>
+
+Engine::Sprite::~Sprite() {
+    delete texture;
+    delete alpha_mask;
+}
+
+void Engine::Sprite::Render() {
+    auto* t = GetTexture();
+    auto* a = GetAlphaMask();
+
+    if (t && !a)
+        return J2D::DrawSprite(t, position, face_angle, origin, scale, base_color);
+    if (t && a)
+        return J2D::DrawSprite(t, a, position, face_angle, origin, scale, base_color);
+}
+
+Texture* Engine::Sprite::GetTexture() {
+    return texture;
+}
+
+Texture* Engine::Sprite::GetAlphaMask() {
+    return alpha_mask;
+}
+
+void Engine::Sprite::SetAlphaMask(Texture* new_alpha_mask) {
+    alpha_mask = new_alpha_mask;
+}

src/Engine/types/entity/mixins/BoxCollider.cpp

@@ -0,0 +1,14 @@
+#include "Engine/types/entity/mixins/BoxCollider.h"
+
+using namespace Engine;
+bool BoxCollider::BoxCollides(BoxCollider* rhs) {
+    if (GetBounds().Intersects(rhs->GetBounds()))
+        return true;
+    if (GetBounds().Contains(rhs->GetBounds()))
+        return true;
+    return false;
+}
+
+bool BoxCollider::BoxCollides(const Vector2& rhs) {
+    return GetBounds().Contains(rhs);
+}

src/Engine/types/scene/Fixed.cpp

@@ -1,4 +1,4 @@
-#include <Engine/Level/Fixed.h>
+#include "Engine/types/scene/Fixed.h"
 
 bool Engine::Fixed::Collidable() const {
     return collidable;

src/Engine/types/scene/Scene.cpp

@@ -1,32 +1,35 @@
-#include <Engine/Level/Scene.h>
-#include <Engine/Entity/Camera.h>
+#include <Engine/types/scene/Scene.h>
+#include <Engine/types/entity/Camera.h>
+#include <Engine/types/entity/InstancedSprite.h>
+#include <JGL/JGL.h>
 #include <algorithm>
 
-bool Engine::Scene::EntityListContains(const Entity* entity) const {
+using namespace Engine;
+bool Scene::EntityListContains(const Entity* entity) const {
     auto flat = GetFlatEntityList(entity_list);
-    
+
     for (auto* e : flat)
         if (e == entity)
             return true;
     return false;
 }
 
-bool Engine::Scene::FixedListContains(const Fixed* fixed) const {
+bool Scene::FixedListContains(const Fixed* fixed) const {
     for (auto* f : fixed_list)
         if (f == fixed)
             return true;
     return false;
 }
 
-size_t Engine::Scene::FixedCount() const {
+size_t Scene::FixedCount() const {
     return fixed_list.size();
 }
 
-size_t Engine::Scene::EntityCount() const {
+size_t Scene::EntityCount() const {
     return GetFlatEntityList(entity_list).size();
 }
 
-void Engine::Scene::Update() {
+void Scene::Update() {
     if (active_camera)
         active_camera->Update();
 
@@ -35,7 +38,7 @@ void Engine::Scene::Update() {
             e->Update();
 }
 
-void Engine::Scene::Render(RenderTarget* render_target) {
+void Scene::Render(RenderTarget* render_target) {
     // The Camera and the HUD are ignored here because they're special cases.
     std::vector<Renderable*> display_list{};
     for (auto* e : GetFlatEntityList(entity_list))
@@ -45,7 +48,7 @@ void Engine::Scene::Render(RenderTarget* render_target) {
                     display_list.push_back(r);
 
     std::sort(display_list.begin(), display_list.end(), [](Renderable* a, Renderable* b) {
-        return a->GetDepth() > b->GetDepth();
+        return a->GetLayer() > b->GetLayer();
     });
 
     J2D::Begin( render_target, true);
@@ -66,7 +69,7 @@ void Engine::Scene::Render(RenderTarget* render_target) {
     J2D::End();
 }
 
-Engine::Scene::~Scene() {
+Scene::~Scene() {
     for (auto* f : fixed_list)
         delete f;
 
@@ -77,7 +80,7 @@ Engine::Scene::~Scene() {
     delete active_camera;
 }
 
-void Engine::Scene::Unload() {
+void Scene::Unload() {
     for (auto* f : fixed_list)
         delete f;
 
@@ -87,50 +90,50 @@ void Engine::Scene::Unload() {
     delete heads_up_display;
 }
 
-void Engine::Scene::AppendEntity(Entity* entity) {
+void Scene::AppendEntity(Entity* entity) {
     if (!EntityListContains(entity))
         entity_list.push_back(entity);
 }
 
-void Engine::Scene::AppendFixed(Fixed* fixed) {
+void Scene::AppendFixed(Fixed* fixed) {
     if (!FixedListContains(fixed))
         fixed_list.push_back(fixed);
 }
 
-void Engine::Scene::DestroyEntity(Entity *entity) {
+void Scene::DestroyEntity(Entity *entity) {
     auto it = std::find(entity_list.begin(), entity_list.end(), entity);
     if (it != entity_list.end())
         delete *it, entity_list.erase(it);
 }
 
-void Engine::Scene::DestroyFixed(Fixed* fixed) {
+void Scene::DestroyFixed(Fixed* fixed) {
     auto it = std::find(fixed_list.begin(), fixed_list.end(), fixed);
     if (it != fixed_list.end())
         delete *it, fixed_list.erase(it);
 }
 
-void Engine::Scene::RemoveEntity(Entity* entity) {
+void Scene::RemoveEntity(Entity* entity) {
     auto it = std::find(entity_list.begin(), entity_list.end(), entity);
     if (it != entity_list.end())
         entity_list.erase(it);
 }
 
 
-void Engine::Scene::RemoveFixed(Fixed* fixed) {
+void Scene::RemoveFixed(Fixed* fixed) {
     auto it = std::find(fixed_list.begin(), fixed_list.end(), fixed);
     if (it != fixed_list.end())
         fixed_list.erase(it);
 }
 
-std::string Engine::Scene::GetName() const {
+std::string Scene::GetName() const {
     return name;
 }
 
-Engine::Camera* Engine::Scene::GetActiveCamera() const {
+Camera* Scene::GetActiveCamera() const {
     return active_camera;
 }
 
-std::vector<Engine::Entity*> Engine::Scene::GetFlatEntityList(const std::vector<Entity*>& ent_list) const {
+std::vector<Entity*> Scene::GetFlatEntityList(const std::vector<Entity*>& ent_list) const {
     std::vector<Entity*> result{};
 
     for (auto* e : ent_list) {
@@ -142,3 +145,28 @@ std::vector<Engine::Entity*> Engine::Scene::GetFlatEntityList(const std::vector<
     return result;
 }
 
+Texture* Scene::GetInstancedTexture(const InstancedSprite* user) {
+    for (auto* itx : instanced_textures)
+        if (itx->InUseBy(user))
+            return itx->GetTexture();
+
+    auto* t = new Texture(user->GetTextureFilesystemPath());
+    auto* itx = new InstancedTexture(t, user);
+    instanced_textures.push_back(itx);
+    return t;
+}
+
+Texture* Scene::GetInstancedAlphaMask(const InstancedSprite* user) {
+    for (auto* itx : instanced_alpha_masks)
+        if (itx->InUseBy(user))
+            return itx->GetTexture();
+
+    if (!user->GetAlphaMaskFilesystemPath().empty()) {
+        auto *t = new Texture(user->GetTextureFilesystemPath());
+        auto *itx = new InstancedTexture(t, user);
+        instanced_textures.push_back(itx);
+        return t;
+    }
+    return nullptr;
+}
+

src/Game/Entities/Box.cpp

@@ -1,4 +1,6 @@
-#include <Game/Entity/Box.h>
+#include <Game/entity/Box.h>
+#include <Engine/Globals.h>
+#include <JGL/JGL.h>
 
 void Game::Box::Render() {
     J2D::FillRect(Colors::Red, Vector2(position), {20, 20});
@@ -13,4 +15,4 @@ void Game::Box::Update() {
         MoveX(-500);
     if (Globals::Window->IsKeyDown(Keys::D))
         MoveX(500);
-    }
+}

src/Game/Entities/DemoGameHud.cpp

@@ -1,5 +1,6 @@
-#include <Game/Entity/DemoGameHud.h>
+#include <Game/entity/DemoGameHud.h>
 #include <Engine/Globals.h>
+#include <JGL/JGL.h>
 
 void Game::DemoGameHud::Render() {
     J2D::DrawString(Colors::Whites::Ivory, "Framerate: " + std::to_string((int) Globals::Window->GetRefreshRate()), 0, 0, 1, 16);

src/Game/Scene/ControllableBox.cpp

@@ -1,6 +1,6 @@
-#include <Game/Scene/ControllableBox.h>
-#include <Game/Entity/DemoGameHud.h>
-#include <Game/Entity/Box.h>
+#include <Game/scene/ControllableBox.h>
+#include <Game/entity/DemoGameHud.h>
+#include <Game/entity/Box.h>
 
 void ControllableBox::Init() {
     auto* hud = new Game::DemoGameHud();

src/Game/Scene/Loading.cpp

@@ -1,5 +1,6 @@
-#include <Game/Scene/Loading.h>
+#include <Game/scene/Loading.h>
 #include <Engine/Globals.h>
+#include <JGL/JGL.h>
 
 void LoadingScreen::Init() {
     RedactedSoftware = new JGL::Texture("assets/sprites/Re3D.png");