feat(entity): add client-to-server entity creation and destruction requests

Extend the network protocol with `C2SEntityCreateRequest` and `C2SEntityDestoryRequest` packets. Refactor entity managers to split public client-facing create/destroy methods that send requests over the network, from internal handlers that process received packets. Add utility functions for converting protobuf Vec3 to glm::vec3.

CMakeLists.txt

@@ -39,6 +39,8 @@ add_subdirectory(third_party/imgui)
 
 add_subdirectory(third_party/dr_libs)
 
+add_subdirectory(third_party/stb)
+
 add_executable(${PROJECT_NAME})
 
 add_subdirectory(src)
@@ -130,14 +132,12 @@ target_link_libraries(${PROJECT_NAME}
     PRIVATE
         SDL3::SDL3                                 
         glad
-        glm::glm
         OpenGL::GL
-        soil2
         Freetype::Freetype
-        tomlplusplus::tomlplusplus
         imgui
         dr_libs
         tbb
+        stb
         protobuf::libprotobuf
         absl::log
         absl::check
@@ -148,6 +148,7 @@ target_link_libraries(${PROJECT_NAME}
         OpenAL::OpenAL
         harfbuzz::harfbuzz
         Opus::Opus
+        assimp::assimp
         $<$<PLATFORM_ID:Windows>:ws2_32>
 
 )

assets/data/block/air.toml

@@ -8,4 +8,5 @@ is_passable = true
 is_transitional = false
 is_transparent = true
 name = 'air'
+name_key = 'block.air'
 roughness = 1.0

assets/data/block/dirt.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = true
 is_transparent = false
 name = 'dirt'
+name_key = 'block.dirt'
 roughness = 1.0

assets/data/block/grass.toml

@@ -8,4 +8,5 @@ is_passable = true
 is_transitional = false
 is_transparent = true
 name = 'grass'
-roughness = 0.9
+name_key = 'block.grass'
+roughness = 0.90000000000000002

assets/data/block/grass_block.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = true
 is_transparent = false
 name = 'grass_block'
-roughness = 0.9
+name_key = 'block.grass_block'
+roughness = 0.90000000000000002

assets/data/block/leaf.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = false
 is_transparent = true
 name = 'leaf'
-roughness = 0.7
+name_key = 'block.leaf'
+roughness = 0.69999999999999996

assets/data/block/log.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = false
 is_transparent = false
 name = 'log'
-roughness = 0.7
+name_key = 'block.log'
+roughness = 0.69999999999999996

assets/data/block/sand.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = true
 is_transparent = false
 name = 'sand'
-roughness = 0.8
+name_key = 'block.sand'
+roughness = 0.80000000000000004

assets/data/block/snowy_grass_block.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = true
 is_transparent = false
 name = 'snowy_grass_block'
-roughness = 0.9
+name_key = 'block.snowy_grass_block'
+roughness = 0.90000000000000002

assets/data/block/stone.toml

@@ -8,4 +8,5 @@ is_passable = false
 is_transitional = true
 is_transparent = false
 name = 'stone'
+name_key = 'block.stone'
 roughness = 0.75

assets/data/block/template.toml

@@ -8,4 +8,5 @@ is_transparent = false
 is_discard = false
 is_blend = false
 is_transitional = false
-roughness = 1.0
+roughness = 1.0
+name_key = "block.template"

assets/data/block/water.toml

@@ -8,4 +8,5 @@ is_passable = true
 is_transitional = false
 is_transparent = true
 name = 'water'
+name_key = 'block.water'
 roughness = 0.02

assets/lang/en_US.json

@@ -35,5 +35,15 @@
     "joingame.join_a_world": "Join A World",
     "joingame.server_ip": "Server Ip",
     "joingame.join_world": "Join World",
-    "error.disable_voice": "Server Disable Voice Chat"
+    "error.disable_voice": "Server Disable Voice Chat",
+    "block.air": "air",
+    "block.dirt": "dirt",
+    "block.grass_block": "grass block",
+    "block.grass": "grass",
+    "block.leaf": "leaf",
+    "block.log": "log",
+    "block.sand": "sand",
+    "block.snowy_grass_block": "snowy grass block",
+    "block.stone": "stone",
+    "block.water": "water"
 }

assets/lang/zh_CN.json

@@ -35,5 +35,15 @@
     "joingame.join_a_world": "加入世界",
     "joingame.server_ip": "服务器IP",
     "joingame.join_world": "加入世界",
-    "error.disable_voice": "服务器已禁用语音聊天"
+    "error.disable_voice": "服务器已禁用语音聊天",
+    "block.air": "空气",
+    "block.dirt": "泥土",
+    "block.grass_block": "草方块",
+    "block.grass": "草",
+    "block.leaf": "树叶",
+    "block.log": "原木",
+    "block.sand": "沙子",
+    "block.snowy_grass_block": "覆雪草方块",
+    "block.stone": "石头",
+    "block.water": "水"
 }

assets/model/creature/pig/collision.json

@@ -0,0 +1,16 @@
+{
+    "boxes": [
+        {
+            "center": [
+                0,
+                0.78,
+                0
+            ],
+            "half": [
+                0.53,
+                0.78,
+                0.406
+            ]
+        }
+    ]
+}

assets/shaders/depth_model_vert.glsl

@@ -7,7 +7,6 @@ uniform mat4 lightSpaceMatrix;
 uniform mat4 modelMatrix;
 
 out vec2 tc;
-flat out int tex_layer;
 
 void main() {
     tc = texCoord;

assets/shaders/model_vert.glsl

@@ -3,7 +3,6 @@
 layout (location = 0) in vec3 pos;
 layout (location = 1) in vec2 texCoord;
 layout (location = 2) in vec3 aNormal;
-layout (location = 3) in vec3 aTangent;
 
 uniform mat4 mv_matrix;
 uniform mat4 proj_matrix;

cmake/Dependencies.cmake

@@ -10,29 +10,8 @@ find_package(harfbuzz REQUIRED)
 find_package(Freetype REQUIRED)
 find_package(SDL3 REQUIRED)
 find_package(Opus REQUIRED)
-
+find_package(assimp REQUIRED)
 # Third-party libraries
-FetchContent_Declare(
-    glm
-    GIT_REPOSITORY https://github.com/g-truc/glm.git
-    GIT_TAG 1.0.3 
-    
-)
-FetchContent_MakeAvailable(glm)
-FetchContent_Declare(
-    soil2
-    GIT_REPOSITORY https://github.com/SpartanJ/SOIL2.git
-    GIT_TAG 1.31  
-    
-)
-FetchContent_MakeAvailable(soil2)
-FetchContent_Declare(
-    tomlplusplus
-    GIT_REPOSITORY https://github.com/marzer/tomlplusplus.git
-    GIT_TAG v3.4.0
-)
-FetchContent_MakeAvailable(tomlplusplus)
-
 
 if (WIN32)
 

include/Cubed/AABB.hpp

@@ -1,20 +0,0 @@
-#pragma once
-#include <glm/glm.hpp>
-
-namespace Cubed {
-
-struct AABB {
-    glm::vec3 min{0.0f, 0.0f, 0.0f};
-    glm::vec3 max{0.0f, 0.0f, 0.0f};
-
-    AABB(glm::vec3 min_point, glm::vec3 max_point)
-        : min(min_point), max(max_point) {}
-
-    bool intersects(const AABB& other) const {
-        return (min.x <= other.max.x && max.x >= other.min.x) &&
-               (min.y <= other.max.y && max.y >= other.min.y) &&
-               (min.z <= other.max.z && max.z >= other.min.z);
-    }
-};
-
-} // namespace Cubed

include/Cubed/app.hpp

@@ -49,7 +49,6 @@ private:
     Window m_window;
 
     TextureManager m_texture_manager;
-
     AudioEngine m_audio;
 
     Renderer m_renderer;

include/Cubed/camera.hpp

@@ -8,7 +8,7 @@
 
 namespace Cubed {
 
-class ClientPlayer;
+class LocalPlayer;
 
 class Camera {
 private:
@@ -18,7 +18,7 @@ private:
         THIRD_PERSON_FRONT,
     };
 
-    ClientPlayer* m_player;
+    LocalPlayer* m_player;
     float m_last_mouse_x, m_last_mouse_y;
     glm::vec3 m_camera_pos;
     bool m_under_water = false;
@@ -35,7 +35,7 @@ public:
 
     void update_move_camera();
 
-    void camera_init(ClientPlayer* player);
+    void camera_init(LocalPlayer* player);
     void hot_reload();
     void update_cursor_position_camera(float offset_x, float offset_y);
 
@@ -47,7 +47,7 @@ public:
     void change_perspective();
     bool is_first_person() const;
     bool handle_event(const Event& e);
-    ClientPlayer* player();
+    LocalPlayer* player();
 };
 
 } // namespace Cubed

include/Cubed/dev_panel.hpp

@@ -7,7 +7,7 @@
 namespace Cubed {
 
 class WorldScene;
-class ClientPlayer;
+class LocalPlayer;
 class App;
 class DevPanel {
     struct ConfigView {
@@ -42,7 +42,7 @@ private:
     WorldScene& m_world_scene;
     Config& m_config;
     ConfigView m_config_view;
-    ClientPlayer* m_player;
+    LocalPlayer* m_player;
     PlayerProfile m_player_profile;
     bool m_need_save_config = false;
     bool m_gen_thread_running = true;
@@ -63,7 +63,7 @@ private:
     void show_server_world_table_bar();
     void show_client_world_table_bar();
     void show_player_tab_item();
-    void show_items_tab_item();
+    // void show_items_tab_item();
     void show_shader_tab_item();
 
     void update_config_view();

include/Cubed/gameplay/block.hpp

@@ -42,6 +42,7 @@ struct LookBlock {
 
 struct BlockData {
     std::string name;
+    std::string name_key;
     BlockType id = 0;
 
     bool is_liquid = false;
@@ -55,11 +56,11 @@ struct BlockData {
     bool is_blend = false;
     bool is_transitional = false;
     float roughness = 1.0f;
-    BlockData(BlockType b_id, std::string_view b_name, bool liquid,
-              bool passable, bool cross_plane, bool transparent, bool gas,
-              bool discard, bool blend, bool transitional, float r)
-        : name(b_name), id(b_id), is_liquid(liquid), is_gas(gas),
-          is_passable(passable), is_cross_plane(cross_plane),
+    BlockData(std::string_view b_name, std::string_view name_k, BlockType b_id,
+              bool liquid, bool passable, bool cross_plane, bool transparent,
+              bool gas, bool discard, bool blend, bool transitional, float r)
+        : name(b_name), name_key(name_k), id(b_id), is_liquid(liquid),
+          is_gas(gas), is_passable(passable), is_cross_plane(cross_plane),
           is_transparent(transparent), is_discard(discard), is_blend(blend),
           is_transitional(transitional), roughness(r) {}
 };
@@ -72,7 +73,7 @@ public:
     static unsigned sums();
     static unsigned cross_plane_sum();
     static const std::string& name_form_id(BlockType id);
-
+    static std::string local_name(BlockType id);
     static bool is_gas(BlockType id);
     static bool is_liquid(BlockType id);
 

include/Cubed/gameplay/chunk.hpp

@@ -0,0 +1,27 @@
+#pragma once
+#include "Cubed/gameplay/chunk_pos.hpp"
+
+#include <glm/glm.hpp>
+#include <tuple>
+namespace Cubed {
+class Chunk {
+public:
+    Chunk() = default;
+    Chunk(const Chunk&) = delete;
+    Chunk(Chunk&&) = delete;
+    Chunk& operator=(const Chunk&) = delete;
+    Chunk& operator=(Chunk&&) = delete;
+    virtual ~Chunk() = default;
+    static int index(int x, int y, int z);
+    static int index(const glm::vec3& pos);
+    static std::tuple<int, int, int> world_to_block(int world_x, int world_y,
+                                                    int world_z, int chunk_x,
+                                                    int chunk_z);
+    static std::tuple<int, int, int> world_to_block(const glm::ivec3& block_pos,
+                                                    ChunkPos chunk_pos);
+    static std::tuple<int, int, int> block_to_world(int x, int y, int z,
+                                                    int chunk_x, int chunk_z);
+    static std::tuple<int, int, int> block_to_world(const glm::ivec3& block_pos,
+                                                    ChunkPos chunk_pos);
+};
+} // namespace Cubed

include/Cubed/gameplay/client_chunk.hpp

@@ -2,6 +2,7 @@
 #include "Cubed/constants.hpp"
 #include "Cubed/gameplay/biome.hpp"
 #include "Cubed/gameplay/block.hpp"
+#include "Cubed/gameplay/chunk.hpp"
 #include "Cubed/gameplay/chunk_pos.hpp"
 #include "Cubed/gameplay/vertex_data.hpp"
 #include "world/chunk_data.pb.h"
@@ -26,7 +27,7 @@ struct ChunkRenderSnapshot {
     glm::vec3 center;
     glm::vec3 half_extents;
 };
-class ClientChunk {
+class ClientChunk : public Chunk {
 public:
     ClientChunk(ClientWorld& world);
     ~ClientChunk();
@@ -35,17 +36,6 @@ public:
     ClientChunk(ClientChunk&&) noexcept;
     ClientChunk& operator=(ClientChunk&&) noexcept;
 
-    static int index(int x, int y, int z);
-    static int index(const glm::vec3& pos);
-    static std::tuple<int, int, int> world_to_block(int world_x, int world_y,
-                                                    int world_z, int chunk_x,
-                                                    int chunk_z);
-    static std::tuple<int, int, int> world_to_block(const glm::ivec3& block_pos,
-                                                    ChunkPos chunk_pos);
-    static std::tuple<int, int, int> block_to_world(int x, int y, int z,
-                                                    int chunk_x, int chunk_z);
-    static std::tuple<int, int, int> block_to_world(const glm::ivec3& block_pos,
-                                                    ChunkPos chunk_pos);
     BiomeType get_biome() const;
     ChunkPos get_chunk_pos() const;
     const std::vector<BlockType>& get_chunk_blocks() const;

include/Cubed/gameplay/client_entity_manager.hpp

@@ -0,0 +1,68 @@
+#pragma once
+#include "Cubed/gameplay/ecs/entity.hpp"
+#include "glm/ext/vector_float3.hpp"
+#include "world/entity.pb.h"
+
+#include <entt/entt.hpp>
+#include <tbb/concurrent_hash_map.h>
+#include <tbb/concurrent_queue.h>
+namespace Cubed {
+class ClientWorld;
+class ClientEntityManager {
+public:
+    enum class Command { CREATE, DESTORY };
+
+    ClientEntityManager(ClientWorld& world);
+    void update();
+    void init();
+
+    void receive_entity_create(S2CEntityCreate& s2c);
+    void receive_entity_destory(EntityID id);
+
+    void destory(EntityID id);
+    void create(std::string_view name, const glm::vec3& pos);
+
+    const entt::registry& get_registry() const;
+
+private:
+    struct EntityCreateElement {
+        EntityID id;
+        std::string name;
+        glm::vec3 pos;
+    };
+    using EntityMap = tbb::concurrent_hash_map<EntityID, entt::entity>;
+    using acc = EntityMap::accessor;
+    using cacc = EntityMap::const_accessor;
+    using CreateFunc = std::function<void(EntityID id)>;
+    using TaskElement = std::variant<EntityCreateElement, EntityID>;
+    using TaskPair = std::pair<Command, TaskElement>;
+
+    ClientWorld& m_world;
+    entt::registry m_registry;
+    EntityMap m_entities;
+    std::unordered_map<std::string_view, CreateFunc> m_factories;
+    tbb::concurrent_queue<TaskPair> m_tasks;
+
+    void handle_task();
+    void handle_entity_destory(EntityID id);
+    // not thread safe
+    void handle_entity_create(EntityID id, std::string_view name,
+                              const glm::vec3& pos);
+    template <typename... Args>
+    void create_entity_in_registry(EntityID id, Args&&... args) {
+        {
+            cacc a;
+            if (m_entities.find(a, id)) {
+                return;
+            }
+        }
+        auto entity = m_registry.create();
+
+        ((m_registry.emplace<std::remove_cvref_t<Args>>(
+             entity, std::forward<Args>(args))),
+         ...);
+        m_entities.emplace(id, entity);
+        return;
+    }
+};
+} // namespace Cubed

include/Cubed/gameplay/client_player.hpp

@@ -1,161 +1,25 @@
 #pragma once
-#include "Cubed/AABB.hpp"
-#include "Cubed/constants.hpp"
-#include "Cubed/gameplay/block.hpp"
-#include "Cubed/gameplay/chunk_pos.hpp"
-#include "Cubed/gameplay/game_mode.hpp"
-#include "Cubed/gameplay/game_time.hpp"
-#include "Cubed/gameplay/player.hpp"
-#include "Cubed/input/event.hpp"
-#include "Cubed/input/input.hpp"
 
-#include <absl/container/flat_hash_set.h>
-#include <glm/glm.hpp>
-#include <optional>
-#include <shared_mutex>
+#include "Cubed/gameplay/ecs/animation.hpp"
+#include "Cubed/gameplay/ecs/identity.hpp"
+#include "Cubed/gameplay/ecs/transform.hpp"
+#include "Cubed/gameplay/player.hpp"
 namespace Cubed {
 
-class ClientWorld;
-class ClientPlayer {
-public:
-    static constexpr float WALK_SOUND_INTERVAL = 0.45f;
-    static constexpr float RUN_SOUND_INTERVAL = 0.3f;
-    using ChunkPosSet = absl::flat_hash_set<ChunkPos, ChunkPos::Hash>;
-    ClientPlayer(ClientWorld& world);
-    ~ClientPlayer();
-
-    bool handle_mouse_button_event(const MouseButtonEvent& e);
-    bool handle_key_event(const KeyEvent& e);
-    bool handle_mouse_wheel_event(const MouseWheelEvent& e);
-
-    void update_front_vec(float offset_x, float offset_y);
-    bool update_player_move_state(Key key, KeyAction action);
-    bool update_scroll(float yoffset);
-
-    void update_chunk_set(const ChunkPosSet& set);
-    const ChunkPosSet& get_chunk_pos_set() const;
-    ChunkPosSet get_chunk_pos_set();
-
-    static AABB get_aabb(const glm::vec3& pos);
-    const glm::vec3& get_front() const;
-    Gait get_gait() const;
-    const std::optional<LookBlock>& get_look_block_pos() const;
-    // thread safe
-    glm::vec3 get_player_pos() const;
-    const MoveState& get_move_state() const;
-
-    void change_mode(GameMode mode);
-    void reload_config();
-    void set_player_pos(const glm::vec3& pos);
-    void set_place_block(unsigned id);
-    void update(float delta_time);
-
-    float& max_walk_speed();
-    float& max_run_speed();
-    float& max_speed();
-    float& acceleration();
-    float& deceleration();
-    float& g();
-    float& fly_y_speed();
-
-    unsigned get_current_block() const;
-
-    void set_gait(Gait gait);
-    GameMode& game_mode();
-
-    ClientWorld& get_world();
-
-    void set_uuid(std::string_view uuid);
-    std::string get_uuid() const;
-    const std::string& get_name() const;
-    void reset_key_status();
-    void init(std::string_view name);
-
-    float yaw() const;
-    float pitch() const;
-    float& angle();
-    float& walk_time();
-    bool ray_cast(const glm::vec3& start, const glm::vec3& dir,
-                  glm::ivec3& block_pos, glm::vec3& normal,
-                  float distance = 4.0f);
-    bool is_underwater() const;
-    void set_underwater(bool u);
-    void place_block(float dt);
-
-private:
-    using enum GameMode;
-    float m_max_walk_speed = DEFAULT_MAX_WALK_SPEED;
-    float m_max_run_speed = DEFAULT_MAX_RUN_SPEED;
-    float m_acceleration = DEFAULT_ACCELERATION;
-    float m_deceleration = DEFAULT_DECELERATION;
-    float m_g = DEFAULT_G;
-    constexpr static float MAX_SPACE_ON_TIME = 0.3f;
-    constexpr static float PLACE_BLOCK_INTERVAL = 0.2f;
-    float m_place_time = PLACE_BLOCK_INTERVAL;
-    std::atomic<float> m_yaw = 0.0f;
-    std::atomic<float> m_pitch = 0.0f;
-
-    float m_sensitivity = 0.15f;
-
-    float m_max_speed = m_max_walk_speed;
-    float m_y_speed = 0.0f;
-    float m_fly_y_speed = 7.5f;
-    bool can_up = true;
-
-    float space_on_time = 0.0f;
-    bool space_on = false;
-    bool is_fly = false;
-
-    float m_xz_speed = 0.0f;
-
-    unsigned m_place_block = 1;
-
-    bool m_moving = false;
-    bool m_sprinting = false;
-    bool m_underwater = false;
-
-    glm::vec3 direction = glm::vec3(0.0f, 0.0f, 0.0f);
-    glm::vec3 move_distance{0.0f, 0.0f, 0.0f};
-    // player is tow block tall, the pos is the lower pos
-
-    glm::vec3 m_player_pos{0.0f, 255.0f, 0.0f};
-    ChunkPos m_last_chunk_pos{0, 0};
-
-    glm::vec3 m_front{0, 0, -1};
-    glm::vec3 m_right{0, 0, 0};
-    static constexpr glm::vec3 M_SIZE{0.6f, 1.8f, 0.6f};
-
-    std::atomic<Gait> m_gait = Gait::STOP;
-    MoveState m_move_state{};
-    MouseState m_mouse_state{};
-    GameMode m_game_mode = CREATIVE;
-    std::optional<LookBlock> m_look_block = std::nullopt;
-    std::string m_name{};
-    mutable std::shared_mutex m_uuid_mutex;
-    std::string m_uuid;
-    ClientWorld& m_world;
-
-    float m_angle{0.0f};
-    float m_walk_time{0.0f};
-
-    std::unordered_map<std::string, Timer> m_timers;
-
-    mutable std::shared_mutex m_player_pos_mutex;
-    mutable std::shared_mutex m_chunk_pos_mutex;
-    ChunkPosSet m_player_chunk_pos_set;
-
-    void update_direction();
-    void update_lookup_block();
-
-    void update_move(float delta_time);
-
-    void update_x_move(glm::vec3& player_pos);
-    void update_y_move(glm::vec3& player_pos);
-    void update_z_move(glm::vec3& player_pos);
-
-    void update_player_chunk();
-
-    void play_walk_sound(float dt);
-    Gait compute_gait() const;
+struct ClientPlayer {
+    Position pos{};
+    Position render_pos{};
+    EntityInfo entity{};
+    WalkPose walk{};
+    Orientation angle{};
+    Orientation render_angle{};
 };
-} // namespace Cubed
+
+struct PlayerRenderData {
+    EntityInfo info{};
+    Position render_pos{};
+    Orientation angle{};
+    Gait gait{};
+};
+
+} // namespace Cubed

include/Cubed/gameplay/client_player_manager.hpp

@@ -0,0 +1,45 @@
+#pragma once
+#include "Cubed/gameplay/client_player.hpp"
+#include "Cubed/gameplay/local_player.hpp"
+#include "Cubed/gameplay/network_client.hpp"
+#include "Cubed/tools/sparse_vector.hpp"
+namespace Cubed {
+class ClientWorld;
+class ClientPlayerManager {
+public:
+    ClientPlayerManager(const ClientPlayerManager&) = delete;
+    ClientPlayerManager(ClientPlayerManager&&) = delete;
+    ClientPlayerManager& operator=(const ClientPlayerManager&) = delete;
+    ClientPlayerManager& operator=(ClientPlayerManager&&) = delete;
+    ClientPlayerManager(ClientWorld& world);
+    ~ClientPlayerManager();
+
+    void init(std::string_view local_name);
+    void update(float dt);
+
+    std::span<PlayerRenderData> render_player_data();
+
+    bool has_player(const Hitbox& hitbox) const;
+
+    LocalPlayer& get_local();
+    const LocalPlayer& get_local() const;
+
+    void receive_remote_player(const PlayerInfoRsp& rsp);
+    void receive_player_logout(const LogoutRsp& rsp);
+
+    void reload_config();
+
+    void report_player_info(NetworkClient* client);
+
+private:
+    ClientWorld& m_world;
+    mutable std::shared_mutex m_players_mutex;
+    using PlayerHandle = SparseVector<ClientPlayer>::Handle;
+    SparseVector<ClientPlayer> m_players;
+    std::vector<PlayerRenderData> m_render_data;
+    std::unordered_map<std::string, PlayerHandle> m_players_handle;
+    LocalPlayer m_local;
+
+    void update_players_data(float dt);
+};
+} // namespace Cubed

include/Cubed/gameplay/client_world.hpp

@@ -5,9 +5,12 @@
 #include "Cubed/gameplay/chat_message.hpp"
 #include "Cubed/gameplay/chunk_pos.hpp"
 #include "Cubed/gameplay/client_chunk.hpp"
-#include "Cubed/gameplay/client_player.hpp"
+#include "Cubed/gameplay/client_entity_manager.hpp"
+#include "Cubed/gameplay/client_player_manager.hpp"
 #include "Cubed/gameplay/game_time.hpp"
+#include "Cubed/gameplay/local_player.hpp"
 #include "Cubed/gameplay/network_client.hpp"
+#include "Cubed/gameplay/world.hpp"
 #include "Cubed/input/event.hpp"
 #include "Cubed/tools/cubed_random.hpp"
 #include "Cubed/tools/priority_thread_pool.hpp"
@@ -19,46 +22,26 @@
 #include <tbb/concurrent_unordered_map.h>
 namespace Cubed {
 
-struct PlayerInfo {
-    std::string name;
-    std::string uuid;
-    glm::vec3 render_pos;
-    glm::vec3 target_pos;
-    float render_yaw;
-    float yaw;
-    float render_pitch;
-    float pitch;
-    Gait gait;
-    float angle = 0.0f;
-    float walk_time = 0.0f;
-    float moving_time = 0.0f;
-};
-
-struct PlayerRenderData {
-    std::string name;
-    std::string uuid;
-    glm::vec3 render_pos;
-    float yaw;
-    float pitch;
-    Gait gait;
-    float angle;
-};
 class WorldScene;
-class ClientWorld {
+class ClientWorld : public World {
 public:
+    ClientWorld(const ClientWorld&) = delete;
+    ClientWorld(ClientWorld&&) = delete;
+    ClientWorld& operator=(const ClientWorld&) = delete;
+    ClientWorld& operator=(ClientWorld&&) = delete;
     ClientWorld(AudioEngine& auido, Config& config, WorldScene& scene);
     ~ClientWorld();
     void init(std::string_view player_name,
               std::shared_ptr<NetworkClient> client);
-    void update(float delta_time);
+    void update(float dt);
     bool handle_event(const Event& e);
     const std::optional<LookBlock>& get_look_block_pos() const;
-    ClientPlayer& get_player();
-    const ClientPlayer& get_player() const;
-    int get_block(const glm::ivec3& block_pos) const;
-    bool is_solid(const glm::ivec3& block_pos) const;
-    bool can_pass_block(const glm::ivec3& block_pos) const;
-    BlockType get_block_tpye(const glm::ivec3& block_pos) const;
+    LocalPlayer& get_player();
+    const LocalPlayer& get_player() const;
+    int get_block(const glm::ivec3& block_pos) const override;
+    bool is_solid(const glm::ivec3& block_pos) const override;
+    bool can_pass_block(const glm::ivec3& block_pos) const override;
+    BlockType get_block_tpye(const glm::ivec3& block_pos) const override;
 
     void rebuild_world();
 
@@ -71,7 +54,6 @@ public:
     void receive_block_change(const BlockChangeRsp& rsp);
     void receive_time(const UpdateTime& rsp);
 
-    void receive_remote_player(const PlayerInfoRsp& rsp);
     void receive_player_logout(const LogoutRsp& rsp);
     void receive_player_water_sound(const PlayerWaterSound& rsp);
     void send_player_water_sound(bool underwater, const glm::vec3& pos);
@@ -90,8 +72,6 @@ public:
     void reset_key_status();
     std::vector<glm::vec4>& planes();
     const std::vector<const ChunkRenderSnapshot*>& render_snapshots() const;
-    const std::vector<PlayerRenderData>& render_player_data() const;
-    std::vector<PlayerRenderData>& render_player_data();
 
     glm::vec3 sunlight_dir() const;
     bool sphere_collide_world(glm::vec3 center, float radius) const;
@@ -99,22 +79,26 @@ public:
     void request_exit();
     bool is_receive_exit();
     int chunk_size() const;
-    static AABB get_block_aabb(const glm::ivec3& pos);
+
     AudioEngine& get_audio();
     const AudioEngine& get_audio() const;
     Config& get_config();
     WorldScene& world_scene();
+    ClientPlayerManager& player_manager();
+    ClientEntityManager& entity_manager();
+    std::shared_ptr<NetworkClient> get_client() const;
     void set_direct_exit();
 
     void receive_chat_message(ChatMsg& msg);
     void send_chat_message(ChatMessage& message);
     void receive_voice_message(VoiceMsg& msg);
     bool enable_voice_chat() const;
+    int get_per_tick_time() const override;
     template <typename Fn>
-    void register_ticktimer(std::string_view id, TickType threshold, Fn&& f) {
-        m_ticktimers.emplace(
-            std::piecewise_construct, std::forward_as_tuple(std::string(id)),
-            std::forward_as_tuple(threshold, std::forward<Fn>(f)));
+    void register_timer(std::string_view id, float threshold, Fn&& f) {
+        m_timers.emplace(std::piecewise_construct,
+                         std::forward_as_tuple(std::string(id)),
+                         std::forward_as_tuple(threshold, std::forward<Fn>(f)));
     }
 
 private:
@@ -135,7 +119,6 @@ private:
                                  ChunkPos::TBBHash>;
     using ChunkPosSet = absl::flat_hash_set<ChunkPos, ChunkPos::Hash>;
     using ChunkPosVector = std::vector<ChunkPos>;
-    using OtherPlayerHashMap = std::unordered_map<std::string, PlayerInfo>;
     using chunk_acc = ChunkHashMap::accessor;
     using chunk_cacc = ChunkHashMap::const_accessor;
 
@@ -146,16 +129,13 @@ private:
 
     static constexpr int WORLD_EXIT_TIMEOUT = 200;
     static constexpr int MAX_UPLOAD_CHUNK_SUM = 16;
-    ClientPlayer m_player;
-    OtherPlayerHashMap m_player_info;
+    ClientEntityManager m_entity_manager;
+    ClientPlayerManager m_player_manager;
     ChunkHashMap m_chunks;
     AudioEngine& m_audio;
     Config& m_config;
     WorldScene& m_world_scene;
     std::vector<glm::vec4> m_planes;
-    std::jthread m_client_thread;
-
-    mutable std::shared_mutex m_player_info_mutex;
 
     tbb::concurrent_queue<std::unique_ptr<ClientChunk>> m_pending_upload_queue;
     tbb::concurrent_queue<ChunkPos> m_dirty_chunk_queue;
@@ -165,9 +145,7 @@ private:
 
     std::deque<ChunkPos> m_dirty_queue;
     std::vector<const ChunkRenderSnapshot*> m_render_snapshots;
-    std::vector<PlayerRenderData> m_render_player_data;
 
-    tbb::concurrent_unordered_map<std::string, TickTimer> m_ticktimers;
     std::unordered_map<std::string, Timer> m_timers;
     std::atomic<bool> m_exit_direct{false};
     std::atomic<bool> m_game_running{false};
@@ -175,6 +153,7 @@ private:
     std::atomic<int> m_rendering_distance{24};
     std::atomic<TickType> m_game_ticks{0};
     std::atomic<TickType> m_day_tick{6000};
+    std::atomic<int> m_per_tick_time = DEFAULT_PER_TICK_TIME;
     std::atomic<bool> m_requesting_chunk{false};
     std::atomic<bool> m_is_rebuilding{false};
     std::atomic<int> m_chunk_task_id{0};
@@ -186,10 +165,6 @@ private:
 
     Random m_random;
 
-    void client_run(std::stop_token token);
-
-    void report_player_info();
-
     void set_block(const glm::ivec3& pos, unsigned id);
 
     void update_chunk(const ChunkPosSet& old, const ChunkPosSet& now);

include/Cubed/gameplay/creatures/pig.hpp

@@ -0,0 +1,6 @@
+#pragma once
+
+namespace Cubed {
+struct PigTag {};
+
+} // namespace Cubed

include/Cubed/gameplay/ecs/animation.hpp

@@ -0,0 +1,13 @@
+#pragma once
+
+#include "Cubed/gameplay/player.hpp"
+namespace Cubed {
+
+struct WalkPose {
+    Gait gait = Gait::STOP;
+    // for arm roll caculate
+    float walk_time = 0.0f;
+    // for sound play
+    float moving_time = 0.0f;
+};
+} // namespace Cubed

include/Cubed/gameplay/ecs/client_entity.hpp

@@ -0,0 +1,14 @@
+#pragma once
+#include "Cubed/gameplay/ecs/animation.hpp"
+#include "Cubed/gameplay/ecs/transform.hpp"
+#include "Cubed/gameplay/model.hpp"
+namespace Cubed {
+struct BaseClientCreature {
+
+    Transform transform;
+
+    WalkPose pose;
+
+    ModelID model;
+};
+} // namespace Cubed

include/Cubed/gameplay/ecs/entity.hpp

@@ -0,0 +1,11 @@
+#pragma once
+#include <cstdint>
+namespace Cubed {
+using EntityID = uint64_t;
+
+struct Entity {
+    EntityID id;
+    explicit Entity(EntityID id) : id(id) {}
+};
+
+} // namespace Cubed

include/Cubed/gameplay/ecs/health.hpp

@@ -0,0 +1,10 @@
+#pragma once
+
+namespace Cubed {
+
+struct Health {
+    float hp = 20;
+    float max_hp = 20;
+};
+
+} // namespace Cubed

include/Cubed/gameplay/ecs/identity.hpp

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <string>
+
+namespace Cubed {
+struct EntityInfo {
+    std::string name;
+    std::string uuid;
+};
+} // namespace Cubed

include/Cubed/gameplay/ecs/movement.hpp

@@ -0,0 +1,26 @@
+#pragma once
+#include "Cubed/constants.hpp"
+
+#include <glm/glm.hpp>
+namespace Cubed {
+struct Velocity {
+
+    glm::vec3 value{0.0f};
+
+    glm::vec3 max{4.5f, 7.5f, 7.5f};
+};
+
+struct Movement {
+
+    float acceleration = DEFAULT_ACCELERATION;
+
+    float deceleration = DEFAULT_DECELERATION;
+
+    float jump_power = 7.5f;
+};
+
+struct Gravity {
+
+    float value = DEFAULT_G;
+};
+} // namespace Cubed

include/Cubed/gameplay/ecs/server_entity.hpp

@@ -0,0 +1,27 @@
+#pragma once
+#include "Cubed/gameplay/ecs/health.hpp"
+#include "Cubed/gameplay/ecs/movement.hpp"
+#include "Cubed/gameplay/ecs/state.hpp"
+#include "Cubed/gameplay/ecs/transform.hpp"
+#include "Cubed/gameplay/hitbox.hpp"
+namespace Cubed {
+
+struct BaseServerCreature {
+    Transform transform{};
+
+    Velocity velocity{};
+
+    Movement movement{};
+
+    MoveState move_state{};
+
+    Direction direction{};
+
+    Gravity gravity{};
+
+    Health health{};
+
+    HitboxID hitbox{};
+};
+
+} // namespace Cubed

include/Cubed/gameplay/ecs/state.hpp

@@ -0,0 +1,18 @@
+#pragma once
+
+namespace Cubed {
+struct MoveState {
+
+    bool forward = false;
+    bool back = false;
+    bool left = false;
+    bool right = false;
+
+    bool down = false;
+    bool up = false;
+
+    bool is_fly = false;
+    bool can_up = true;
+};
+
+} // namespace Cubed

include/Cubed/gameplay/ecs/transform.hpp

@@ -0,0 +1,24 @@
+#pragma once
+#include <glm/glm.hpp>
+namespace Cubed {
+struct Position {
+    glm::vec3 value{0.0f};
+};
+
+struct Orientation {
+    float yaw = 0.0f;
+    float pitch = 0.0f;
+    float roll = 0.0f;
+};
+
+struct Direction {
+    glm::vec3 value{0.0f};
+};
+
+struct Transform {
+    Position position{};
+    Orientation orientation{};
+    Direction direction{};
+};
+
+} // namespace Cubed

include/Cubed/gameplay/hitbox.hpp

@@ -0,0 +1,26 @@
+#pragma once
+#include <glm/glm.hpp>
+
+namespace Cubed {
+
+using HitboxID = uint32_t;
+
+struct Hitbox {
+    glm::vec3 center{0.0f};
+    glm::vec3 half{0.0f};
+
+    Hitbox(glm::vec3 center_point, glm::vec3 half_size)
+        : center(center_point), half(half_size) {}
+
+    glm::vec3 min() const { return center - half; }
+
+    glm::vec3 max() const { return center + half; }
+
+    bool intersects(const Hitbox& other) const {
+        return (glm::abs(center.x - other.center.x) <= half.x + other.half.x) &&
+               (glm::abs(center.y - other.center.y) <= half.y + other.half.y) &&
+               (glm::abs(center.z - other.center.z) <= half.z + other.half.z);
+    }
+};
+
+} // namespace Cubed

include/Cubed/gameplay/hitbox_manager.hpp

@@ -0,0 +1,37 @@
+#pragma once
+#include "Cubed/gameplay/hitbox.hpp"
+
+#include <tbb/concurrent_hash_map.h>
+namespace Cubed {
+class HitboxManager {
+public:
+    struct Handle {
+        Hitbox box;
+        HitboxID id = 0;
+    };
+    HitboxManager();
+    ~HitboxManager();
+    static HitboxManager& instance();
+
+    [[nodiscard]]
+    Handle get_hitbox(const std::string& key);
+    [[nodiscard]]
+    Handle get_hitbox(HitboxID id);
+    [[nodiscard]]
+    static Handle hitbox(const std::string& name);
+    [[nodiscard]]
+    static Handle hitbox(HitboxID id);
+    HitboxID get_hitbox_id(const std::string& name);
+    const std::string& get_hitbox_name(HitboxID id);
+
+private:
+    using HitboxMap = tbb::concurrent_hash_map<HitboxID, Hitbox>;
+    using IDMap = tbb::concurrent_hash_map<std::string, HitboxID>;
+    using NameMap = tbb::concurrent_hash_map<HitboxID, std::string>;
+    HitboxID m_next = 0;
+    IDMap m_id_map;
+    NameMap m_name_map;
+    HitboxMap m_hitboxes;
+    Handle load(std::string_view name);
+};
+} // namespace Cubed

include/Cubed/gameplay/item_stack.hpp

@@ -0,0 +1,8 @@
+#pragma once
+#include "Cubed/gameplay/block.hpp"
+namespace Cubed {
+struct ItemStack {
+    BlockType type = 0;
+    size_t sum = 0;
+};
+} // namespace Cubed

include/Cubed/gameplay/local_player.hpp

@@ -0,0 +1,160 @@
+#pragma once
+#include "Cubed/constants.hpp"
+#include "Cubed/gameplay/block.hpp"
+#include "Cubed/gameplay/chunk_pos.hpp"
+#include "Cubed/gameplay/ecs/animation.hpp"
+#include "Cubed/gameplay/ecs/identity.hpp"
+#include "Cubed/gameplay/ecs/movement.hpp"
+#include "Cubed/gameplay/ecs/state.hpp"
+#include "Cubed/gameplay/ecs/transform.hpp"
+#include "Cubed/gameplay/game_mode.hpp"
+#include "Cubed/gameplay/game_time.hpp"
+#include "Cubed/gameplay/hitbox.hpp"
+#include "Cubed/gameplay/item_stack.hpp"
+#include "Cubed/gameplay/player.hpp"
+#include "Cubed/input/event.hpp"
+#include "Cubed/input/input.hpp"
+
+#include <absl/container/flat_hash_set.h>
+#include <glm/glm.hpp>
+#include <optional>
+#include <shared_mutex>
+namespace Cubed {
+
+class ClientWorld;
+class LocalPlayer {
+public:
+    static constexpr size_t HOTBAR_SUM = 10;
+    static constexpr float WALK_SOUND_INTERVAL = 0.45f;
+    static constexpr float RUN_SOUND_INTERVAL = 0.3f;
+    using ChunkPosSet = absl::flat_hash_set<ChunkPos, ChunkPos::Hash>;
+    LocalPlayer(ClientWorld& world);
+    ~LocalPlayer();
+
+    bool handle_mouse_button_event(const MouseButtonEvent& e);
+    bool handle_key_event(const KeyEvent& e);
+    bool handle_mouse_wheel_event(const MouseWheelEvent& e);
+
+    void update_front_vec(float offset_x, float offset_y);
+    bool update_player_move_state(Key key, KeyAction action);
+    bool update_scroll(float yoffset);
+
+    void update_chunk_set(const ChunkPosSet& set);
+
+    const ChunkPosSet& get_chunk_pos_set() const;
+    ChunkPosSet get_chunk_pos_set();
+
+    const glm::vec3& get_front() const;
+
+    const std::optional<LookBlock>& get_look_block_pos() const;
+    // thread safe
+    glm::vec3 get_player_pos() const;
+    const MoveState& get_move_state() const;
+
+    void change_mode(GameMode mode);
+    void reload_config();
+    void set_player_pos(const glm::vec3& pos);
+    void update(float delta_time);
+
+    float& max_walk_speed();
+    float& max_run_speed();
+    float& fly_y_speed();
+
+    const ItemStack& get_current_itemstack() const;
+
+    GameMode& game_mode();
+
+    ClientWorld& get_world();
+
+    void set_uuid(std::string_view uuid);
+    std::string get_uuid() const;
+    const std::string& get_name() const;
+    void reset_input_status();
+    void init(std::string_view name);
+
+    bool ray_cast(const glm::vec3& start, const glm::vec3& dir,
+                  glm::ivec3& block_pos, glm::vec3& normal,
+                  float distance = 4.0f);
+    bool is_underwater() const;
+    void set_underwater(bool u);
+    void place_block(float dt);
+
+    int selected_hotbar() const;
+    void set_hotbar(int pos, const ItemStack& item);
+    std::span<const ItemStack, HOTBAR_SUM> get_hotbar() const;
+
+    glm::vec3& max_speed();
+    float& acceleration();
+    float& deceleration();
+    float& g();
+    void set_gait(Gait gait);
+    float yaw() const;
+    float pitch() const;
+    float& roll();
+    float& walk_time();
+    Gait get_gait() const;
+
+private:
+    using enum GameMode;
+    float m_max_walk_speed = DEFAULT_MAX_WALK_SPEED;
+    float m_max_run_speed = DEFAULT_MAX_RUN_SPEED;
+    float m_max_y_speed = 7.5f;
+    static constexpr float MAX_SPACE_ON_TIME = 0.3f;
+    static constexpr float PLACE_BLOCK_INTERVAL = 0.2f;
+
+    EntityInfo m_info;
+    Position m_pos;
+    WalkPose m_walk_pose;
+    Velocity m_velocity;
+    Orientation m_angle;
+    Movement m_movement;
+    Gravity m_gravity;
+    MoveState m_move_state;
+    Direction m_direction;
+    HitboxID m_hitbox = 0;
+
+    float m_place_time = PLACE_BLOCK_INTERVAL;
+
+    std::array<ItemStack, HOTBAR_SUM> m_hotbar;
+    float m_sensitivity = 0.15f;
+
+    float space_on_time = 0.0f;
+    bool space_on = false;
+
+    int m_selected_hotbar = 0;
+
+    bool m_moving = false;
+    bool m_sprinting = false;
+    bool m_underwater = false;
+
+    // player is tow block tall, the pos is the lower pos
+    ChunkPos m_last_chunk_pos{0, 0};
+
+    glm::vec3 m_front{0, 0, -1};
+    glm::vec3 m_right{0, 0, 0};
+
+    MouseState m_mouse_state{};
+    GameMode m_game_mode = CREATIVE;
+    std::optional<LookBlock> m_look_block = std::nullopt;
+    std::string m_name{};
+    mutable std::shared_mutex m_uuid_mutex;
+    std::string m_uuid;
+    ClientWorld& m_world;
+
+    std::unordered_map<std::string, Timer> m_timers;
+
+    mutable std::shared_mutex m_player_pos_mutex;
+    mutable std::shared_mutex m_chunk_pos_mutex;
+    ChunkPosSet m_player_chunk_pos_set;
+
+    void update_direction();
+    void update_lookup_block();
+
+    void update_move(float delta_time);
+
+    void update_player_chunk();
+
+    void play_walk_sound(float dt);
+    Gait compute_gait() const;
+};
+} // namespace Cubed

include/Cubed/gameplay/model.hpp

@@ -0,0 +1,7 @@
+#pragma once
+#include <cstdint>
+
+using ModelID = uint32_t;
+struct Model {
+    ModelID id;
+};

include/Cubed/gameplay/packet.hpp

@@ -61,6 +61,10 @@ enum class PacketEnum : uint16_t {
     BLOCK_CHANGE_RSP = 3004,
     S2C_CLEAR_ALL_CHUNKS = 3005,
     UPDATE_TIME = 3006,
+    S2C_ENTITY_CREATE = 3007,
+    S2C_ENTITY_DESTORY = 3008,
+    C2S_ENTITY_CREATE_REQUEST = 3009,
+    C2S_ENTITY_DESTORY_REQUEST = 3010,
     CHAT_MSG = 4001,
     VOICE_MSG = 4002,
     PING = 9001,
@@ -111,6 +115,18 @@ template <> constexpr uint16_t get_packet_id<BlockChangeRsp>() {
 template <> constexpr uint16_t get_packet_id<S2C_ClearAllChunks>() {
     return std::to_underlying(PacketEnum::S2C_CLEAR_ALL_CHUNKS);
 }
+template <> constexpr uint16_t get_packet_id<S2CEntityCreate>() {
+    return std::to_underlying(PacketEnum::S2C_ENTITY_CREATE);
+}
+template <> constexpr uint16_t get_packet_id<S2CEntityDestory>() {
+    return std::to_underlying(PacketEnum::S2C_ENTITY_DESTORY);
+}
+template <> constexpr uint16_t get_packet_id<C2SEntityCreateRequest>() {
+    return std::to_underlying(PacketEnum::C2S_ENTITY_CREATE_REQUEST);
+}
+template <> constexpr uint16_t get_packet_id<C2SEntityDestoryRequest>() {
+    return std::to_underlying(PacketEnum::C2S_ENTITY_DESTORY_REQUEST);
+}
 template <> constexpr uint16_t get_packet_id<UpdateTime>() {
     return std::to_underlying(PacketEnum::UPDATE_TIME);
 }
@@ -180,6 +196,12 @@ Packet make_packet(const T& msg) {
     return packet;
 }
 
+template <typename T>
+    requires std::derived_from<T, google::protobuf::Message>
+Packet make_packet(const T* msg) {
+    return make_packet(*msg);
+}
+
 inline PacketHeader decode_packet_header(std::span<const uint8_t> header) {
     if (header.size() < HEADER_LEN)
         throw std::runtime_error("Invalid header");

include/Cubed/gameplay/player.hpp

@@ -1,4 +1,6 @@
 #pragma once
+#include "glm/ext/vector_float3.hpp"
+
 #include <stdexcept>
 #include <utility>
 namespace Cubed {
@@ -17,5 +19,5 @@ inline Gait get_gait_from_id(int id) {
         throw std::runtime_error("Unknown Gait");
     }
 }
-
+static constexpr glm::vec3 PLAYER_SIZE{0.6f, 1.8f, 0.6f};
 } // namespace Cubed

include/Cubed/gameplay/server_chunk.hpp

@@ -2,6 +2,7 @@
 #include "Cubed/constants.hpp"
 #include "Cubed/gameplay/biome.hpp"
 #include "Cubed/gameplay/block.hpp"
+#include "Cubed/gameplay/chunk.hpp"
 #include "Cubed/gameplay/chunk_generator.hpp"
 #include "Cubed/gameplay/chunk_pos.hpp"
 
@@ -11,7 +12,7 @@
 #include <tuple>
 namespace Cubed {
 class ServerWorld;
-class ServerChunk {
+class ServerChunk : public Chunk {
 public:
     ServerChunk(ServerWorld& world, ChunkPos chunk_pos,
                 bool temp_chunk = false);

include/Cubed/gameplay/server_entity_manager.hpp

@@ -0,0 +1,59 @@
+#pragma once
+#include "Cubed/gameplay/ecs/entity.hpp"
+#include "glm/ext/vector_float3.hpp"
+
+#include <entt/entt.hpp>
+#include <tbb/concurrent_hash_map.h>
+#include <tbb/concurrent_queue.h>
+namespace Cubed {
+class ServerWorld;
+class Session;
+class ServerEntityManager {
+public:
+    ServerEntityManager(ServerWorld& world);
+
+    void init();
+    void update();
+    // not thread safe
+    void add_entity(std::string_view name, const glm::vec3& pos);
+    void destory(EntityID id);
+    void handle_player_login(std::shared_ptr<Session> session);
+
+private:
+    enum class Command { CREATE, SEND_ALL_ENTITIES, DESTORY };
+    struct EntityCreateElement {
+        std::string name;
+        glm::vec3 pos;
+    };
+    using EntityMap = tbb::concurrent_hash_map<EntityID, entt::entity>;
+    using acc = EntityMap::accessor;
+    using cacc = EntityMap::const_accessor;
+    using CreateFunc = std::function<EntityID()>;
+    using TaskElement =
+        std::variant<std::shared_ptr<Session>, EntityCreateElement, EntityID>;
+    using TaskPair = std::pair<Command, TaskElement>;
+    ServerWorld& m_world;
+    tbb::concurrent_queue<TaskPair> m_tasks;
+    entt::registry m_registry;
+    EntityID m_next = 0;
+    EntityMap m_entities;
+    std::unordered_map<std::string_view, CreateFunc> m_factories;
+    void create_entity(std::string_view name, const glm::vec3& pos);
+    void handle_entity_create(EntityID id, std::string_view name,
+                              const glm::vec3& pos);
+    void handle_entity_destory(EntityID id);
+    void handle_task();
+    void send_all_entities(std::shared_ptr<Session>& session);
+    template <typename... Args>
+    EntityID create_entity_in_factory(Args&&... args) {
+        auto entity = m_registry.create();
+
+        ((m_registry.emplace<std::remove_cvref_t<Args>>(
+             entity, std::forward<Args>(args))),
+         ...);
+        auto id = m_next++;
+        m_entities.emplace(id, entity);
+        return id;
+    }
+};
+} // namespace Cubed

include/Cubed/gameplay/server_world.hpp

@@ -7,7 +7,9 @@
 #include "Cubed/gameplay/packet.hpp" // IWYU pragma: keep
 #include "Cubed/gameplay/river_worm.hpp"
 #include "Cubed/gameplay/server_chunk.hpp"
+#include "Cubed/gameplay/server_entity_manager.hpp"
 #include "Cubed/gameplay/server_player.hpp"
+#include "Cubed/gameplay/world.hpp"
 #include "Cubed/tools/priority_thread_pool.hpp"
 #include "Cubed/tools/recent_queue.hpp"
 #include "Cubed/tools/sensitive_filter.hpp"
@@ -25,7 +27,7 @@
 #include <vector>
 namespace Cubed {
 class Session;
-class ServerWorld {
+class ServerWorld : public World {
 public:
     enum class ThreadPoolKind { NET, GEN };
     ServerWorld(Config& config);
@@ -84,7 +86,19 @@ public:
 
     void handle_chat_message(ChatMsg& msg);
     void handle_voice_message(VoiceMsg& msg);
+
+    void handle_entity_create(C2SEntityCreateRequest& req);
+    void handle_entity_destory(C2SEntityDestoryRequest& req);
+
     int chunk_size() const;
+
+    std::vector<std::shared_ptr<Session>> get_all_session() const;
+
+    int get_block(const glm::ivec3& block_pos) const override;
+    bool is_solid(const glm::ivec3& block_pos) const override;
+    bool can_pass_block(const glm::ivec3& block_pos) const override;
+    BlockType get_block_tpye(const glm::ivec3& block_pos) const override;
+    int get_per_tick_time() const override;
     template <typename Fn>
     void register_timer(std::string_view id, TickType threshold, Fn&& f) {
         m_timers.emplace(std::piecewise_construct,
@@ -119,13 +133,13 @@ private:
     using PlayerUUIDMap = tbb::concurrent_hash_map<std::string, std::string>;
 
     using chunk_acc = ChunkHashMap::accessor;
-    using chunk_caac = ChunkHashMap::const_accessor;
+    using chunk_cacc = ChunkHashMap::const_accessor;
 
     using uuid_acc = PlayerUUIDMap::accessor;
     using uuid_cacc = PlayerUUIDMap::const_accessor;
 
     Config& m_config;
-
+    ServerEntityManager m_entity_manager;
     // key = uuid
     PlayerHashMap m_players;
     ChunkHashMap m_chunks;
@@ -155,7 +169,7 @@ private:
     std::atomic<bool> m_tick_running{true};
     std::atomic<int> m_per_tick_time = DEFAULT_PER_TICK_TIME; // ms
 
-    mutable std::shared_mutex m_player_mutex;
+    mutable std::shared_mutex m_players_mutex;
     std::mutex m_need_gen_queue_mutex;
     std::condition_variable_any m_gen_cv;
 

include/Cubed/gameplay/systems/physical_system.hpp

@@ -0,0 +1,19 @@
+#pragma once
+#include "Cubed/gameplay/ecs/movement.hpp"
+#include "Cubed/gameplay/ecs/state.hpp"
+#include "Cubed/gameplay/ecs/transform.hpp"
+#include "Cubed/gameplay/world.hpp"
+namespace Cubed {
+
+class PhysicalSystem {
+public:
+    static glm::vec3 get_move_distance(float dt, const Direction& d,
+                                       const Velocity& v);
+
+    static std::tuple<bool, bool, bool>
+    update(float dt, World& world, glm::vec3& moved_pos, Velocity& v,
+           Direction& direction, MoveState& move_state, HitboxID hitbox);
+
+private:
+};
+} // namespace Cubed

include/Cubed/gameplay/systems/speed_system.hpp

@@ -0,0 +1,16 @@
+#pragma once
+
+#include "Cubed/gameplay/ecs/movement.hpp"
+#include "Cubed/gameplay/ecs/state.hpp"
+#include "Cubed/gameplay/ecs/transform.hpp"
+
+namespace Cubed {
+class SpeedSystem {
+public:
+    static void update(float dt, Velocity& v, MoveState& move_state,
+                       Movement& movement, Direction& direction,
+                       const Gravity& g);
+
+private:
+};
+} // namespace Cubed

include/Cubed/gameplay/world.hpp

@@ -0,0 +1,29 @@
+#pragma once
+#include "Cubed/gameplay/block.hpp"
+#include "Cubed/gameplay/hitbox.hpp"
+
+#include <glm/glm.hpp>
+namespace Cubed {
+class World {
+public:
+    World() = default;
+    World(const World&) = delete;
+    World(World&&) = delete;
+    World& operator=(const World&) = delete;
+    World& operator=(World&&) = delete;
+    virtual ~World() = default;
+
+    virtual int get_block(const glm::ivec3& block_pos) const = 0;
+    virtual bool is_solid(const glm::ivec3& block_pos) const = 0;
+    virtual bool can_pass_block(const glm::ivec3& block_pos) const = 0;
+    virtual BlockType get_block_tpye(const glm::ivec3& block_pos) const = 0;
+    virtual int get_per_tick_time() const = 0;
+
+    static Hitbox get_block_aabb(const glm::ivec3& pos) {
+        return {glm::vec3{static_cast<float>(pos.x) + 0.5f,
+                          static_cast<float>(pos.y) + 0.5f,
+                          static_cast<float>(pos.z) + 0.5f},
+                glm::vec3{0.5f, 0.5f, 0.5f}};
+    }
+};
+} // namespace Cubed

include/Cubed/input/input.hpp

@@ -2,15 +2,6 @@
 
 namespace Cubed {
 
-struct MoveState {
-    bool forward = false;
-    bool back = false;
-    bool left = false;
-    bool right = false;
-    bool down = false;
-    bool up = false;
-};
-
 struct MouseState {
     bool left = false;
     bool right = false;

include/Cubed/render/model_manager.hpp

@@ -0,0 +1,45 @@
+#pragma once
+#include "Cubed/gameplay/model.hpp"
+#include "Cubed/render/model_node.hpp"
+#include "Cubed/tools/model_loader.hpp"
+
+#include <tbb/concurrent_hash_map.h>
+namespace Cubed {
+class ModelManager {
+public:
+    struct Handle {
+        const ModelNode& node;
+        ModelID id = 0;
+    };
+
+    ModelManager();
+    ModelManager(const ModelManager&) = delete;
+    ModelManager(ModelManager&&) = delete;
+    ModelManager& operator=(const ModelManager&) = delete;
+    ModelManager& operator=(ModelManager&&) = delete;
+    static ModelManager& instance();
+    ~ModelManager();
+    [[nodiscard]]
+    Handle get_model(const std::string& model_name);
+    [[nodiscard]]
+    Handle get_model(ModelID id);
+    [[nodiscard]]
+    static Handle model(const std::string& model_name);
+    [[nodiscard]]
+    static Handle model(ModelID id);
+    ModelID get_model_id(const std::string& name);
+    const std::string& get_model_name(ModelID id);
+    void init();
+
+private:
+    ModelLoader m_loader;
+    ModelID m_next = 0;
+    using ModelMap = tbb::concurrent_hash_map<ModelID, ModelNode>;
+    using IDMap = tbb::concurrent_hash_map<std::string, ModelID>;
+    using NameMap = tbb::concurrent_hash_map<ModelID, std::string>;
+    ModelMap m_models;
+    IDMap m_id_map;
+    NameMap m_name_map;
+    Handle load_model(std::string_view model_name);
+};
+} // namespace Cubed

include/Cubed/render/model_node.hpp

@@ -0,0 +1,42 @@
+#pragma once
+
+#include "Cubed/primitive_data.hpp"
+#include "Cubed/render/texture.hpp"
+#include "Cubed/render/vertex_array.hpp"
+#include "Cubed/render/vertex_buffer.hpp"
+
+#include <glad/glad.h>
+#include <glm/glm.hpp>
+#include <memory>
+#include <string>
+namespace Cubed {
+
+struct Mesh {
+    std::vector<Vertex3D> vertices;
+    std::vector<uint32_t> indices;
+    std::unique_ptr<VertexBuffer> vbo;
+    std::unique_ptr<VertexBuffer> ebo;
+    std::unique_ptr<VertexArray> vao;
+    std::unique_ptr<Texture> texture;
+    void upload() {
+        vao = std::make_unique<VertexArray>();
+        vao->bind();
+        vbo = std::make_unique<VertexBuffer>();
+        vbo->buffer_data(vertices.data(), vertices.size() * sizeof(Vertex3D));
+        ebo = std::make_unique<VertexBuffer>(BufferType::ELEMENT_ARRAY_BUFFER);
+        ebo->buffer_data(indices.data(), indices.size() * sizeof(uint32_t));
+        vao->attribute(0, 3, GL_FLOAT, sizeof(Vertex3D), (void*)0);
+        vao->attribute(1, 2, GL_FLOAT, sizeof(Vertex3D),
+                       (void*)offsetof(Vertex3D, s));
+        vao->attribute(2, 3, GL_FLOAT, sizeof(Vertex3D),
+                       (void*)offsetof(Vertex3D, nx));
+    };
+};
+struct ModelNode {
+    std::string name;
+    glm::mat4 transform{1.0f};
+    std::vector<Mesh> meshes;
+    std::vector<ModelNode> children;
+};
+
+} // namespace Cubed

include/Cubed/render/model_renderer.hpp

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "Cubed/gameplay/model.hpp"
+#include "Cubed/render/model_node.hpp"
+#include "Cubed/shader.hpp"
+
+#include <glm/glm.hpp>
+namespace Cubed {
+class Renderer;
+class Camera;
+class ModelRender {
+public:
+    ModelRender(Renderer& renderer);
+    void render_model(ModelID id, const glm::vec3& pos, Camera& camera);
+
+    void shadow_pass(ModelID id, const glm::vec3& pos, Camera& camera);
+
+private:
+    Renderer& m_renderer;
+    void render_node(const ModelNode& node, const glm::mat4& parent,
+                     const glm::mat4& view, const Shader& shader, bool shadow);
+    void render_mesh(const Mesh& mesh, bool shadow);
+};
+} // namespace Cubed

include/Cubed/render/player_renderer.hpp

@@ -13,9 +13,7 @@ public:
     PlayerRenderer(Renderer& renderer);
     ~PlayerRenderer();
     void init();
-    void render(const Shader& shader, ClientWorld& world);
-    void shadow_render(const Shader& shader, glm::mat4& light_matrix,
-                       ClientWorld& world);
+    void render(const Shader& shader, ClientWorld& world, bool shadow_render);
 
 private:
     struct PlayerVertex {

include/Cubed/render/renderer.hpp

@@ -4,6 +4,7 @@
 #include "Cubed/constants.hpp"
 #include "Cubed/input/event.hpp"
 #include "Cubed/primitive_data.hpp"
+#include "Cubed/render/model_renderer.hpp"
 #include "Cubed/render/player_renderer.hpp"
 #include "Cubed/render/shader_manager.hpp"
 #include "Cubed/render/vertex_array.hpp"
@@ -19,6 +20,7 @@
 namespace Cubed {
 class TextureManager;
 class ClientWorld;
+class ModelManager;
 class DevPanel;
 class Renderer {
 public:
@@ -79,9 +81,10 @@ public:
 
     bool handle_event(const Event& e);
 
+    ModelRender& model_renderer();
+
 private:
     TextureManager& m_texture_manager;
-
     bool m_init = false;
 
     float m_aspect = 0.0f;
@@ -118,6 +121,7 @@ private:
     std::vector<Vertex2D> m_ui;
 
     WorldRenderer m_world_renderer;
+    ModelRender m_model_renderer;
     Config& m_config;
 
     bool handle_window_resize_event(const WindowResizeEvent& e);

include/Cubed/render/texture.hpp

@@ -38,9 +38,11 @@ enum TextureFormat : GLenum {
     R8 = GL_R8,
     RGB = GL_RGB,
     RGBA8 = GL_RGBA8,
+    BGRA = GL_BGRA
 
 };
-
+// You need to set the texture scaling method, otherwise it will render as
+// black.
 class Texture {
 public:
     explicit Texture(TextureType type);

include/Cubed/render/world_renderer.hpp

@@ -132,7 +132,8 @@ private:
 
     void render_underwater(ClientWorld& world);
     void render_outline(ClientWorld& world);
-    void render_player(ClientWorld& world);
+    void shadow_entity(ClientWorld& world, const glm::mat4& light_matrix);
+    void render_entity(ClientWorld& world);
 
     void render_normal_block(const glm::mat4& model_mat,
                              const glm::mat4& mv_mat, const glm::mat4& norm_mat,

include/Cubed/scene/world_scene.hpp

@@ -6,6 +6,7 @@
 #include "Cubed/gameplay/network_server.hpp"
 #include "Cubed/scene/scene.hpp"
 #include "Cubed/ui/error_ui.hpp"
+#include "Cubed/ui/inventory_ui.hpp"
 #include "Cubed/ui/pasue_menu_ui_manager.hpp"
 #include "Cubed/ui/world_ui_manager.hpp"
 namespace Cubed {
@@ -42,6 +43,7 @@ public:
     bool is_recording() const;
 
 private:
+    enum class PauseUI { PAUSE_MENU, INVENTORY };
     SceneManager& m_scene_manager;
     DevPanel m_dev_panel;
     Camera m_camera;
@@ -53,6 +55,8 @@ private:
     bool m_show_dev_pannel = true;
     bool m_chatting = false;
     PauseMenuUIManager m_pasue_menu;
+    InventoryUI m_inventory_ui;
+    PauseUI m_paused_ui = PauseUI::PAUSE_MENU;
     WorldUIManager m_hud_ui;
     ErrorUI m_error_ui;
     const Argument& m_argument;

include/Cubed/texture_manager.hpp

@@ -48,7 +48,7 @@ public:
     const Texture* get_cross_plane_array() const;
     const Texture* get_image_texture(const std::string& path);
     const Texture* get_pbr_texture() const;
-    const std::vector<std::unique_ptr<Texture>>& item_textures() const;
+    const std::vector<std::unique_ptr<Texture>>& get_item_textures() const;
     const Texture* get_skin() const;
     void init_texture();
 

include/Cubed/tools/cubed_concepts.hpp

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <type_traits>
+namespace Cubed {
+template <typename T>
+concept Ptr = std::is_pointer_v<T>;
+}

include/Cubed/tools/model_loader.hpp

@@ -0,0 +1,22 @@
+#pragma once
+#include "Cubed/render/model_node.hpp"
+
+#include <assimp/Importer.hpp>
+#include <assimp/scene.h>
+namespace Cubed {
+
+class ModelLoader {
+public:
+    ModelLoader();
+    ModelNode load(const std::string& path);
+
+private:
+    Assimp::Importer m_importer;
+    ModelNode process_node(aiNode* node, const aiScene* scene);
+    Mesh process_mesh(aiMesh* mesh, const aiScene* scene);
+    bool process_texture(Mesh& mesh, aiMaterial* material, const aiScene* scene,
+                         aiTextureType type);
+    glm::mat4 convert_matrix(const aiMatrix4x4& matrix);
+};
+
+} // namespace Cubed

include/Cubed/tools/name_space.hpp

@@ -0,0 +1,19 @@
+#pragma once
+
+#include <string_view>
+#include <vector>
+namespace Cubed {
+inline std::vector<std::string_view> parse_namespace(std::string_view str) {
+    std::vector<std::string_view> space;
+    space.reserve(4);
+    std::size_t p = str.find(':');
+    std::size_t start = 0;
+    while (p != std::string_view::npos) {
+        space.emplace_back(str.substr(start, p));
+        start = p + 1;
+        p = str.find(':', p + 1);
+    }
+    space.emplace_back(str.substr(start));
+    return space;
+}
+} // namespace Cubed

include/Cubed/tools/net_utils.hpp

@@ -0,0 +1,21 @@
+#pragma once
+
+#include "Cubed/tools/cubed_concepts.hpp"
+#include "common/vector3.pb.h"
+#include "glm/ext/vector_float3.hpp"
+namespace Cubed {
+namespace Tools {
+template <Ptr T> void set_net_pos(T ptr, const glm::vec3& pos) {
+    Vec3* p = ptr->mutable_pos();
+    p->set_x(pos.x);
+    p->set_y(pos.y);
+    p->set_z(pos.z);
+}
+inline glm::vec3 get_net_pos(const Vec3* p) {
+    return glm::vec3{p->x(), p->y(), p->z()};
+}
+inline glm::vec3 get_net_pos(const Vec3& p) {
+    return glm::vec3{p.x(), p.y(), p.z()};
+}
+} // namespace Tools
+} // namespace Cubed

include/Cubed/tools/shader_tools.hpp

@@ -1,6 +1,5 @@
 #pragma once
 
-#include <SOIL2.h>
 #include <glad/glad.h>
 #include <string>
 #include <utility>
@@ -48,7 +47,7 @@ bool check_opengl_error();
 std::string read_shader_source(const std::string& file_path);
 
 ImageData load_image_data(const std::string& tex_image_path,
-                          bool check_exist = true);
+                          bool check_exist = true, bool full_path = false);
 
 } // namespace Tools
 

include/Cubed/tools/sparse_vector.hpp

@@ -0,0 +1,318 @@
+#pragma once
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+#include <iterator>
+#include <optional>
+#include <utility>
+#include <vector>
+namespace Cubed {
+template <typename T> class SparseVector {
+private:
+    std::vector<std::optional<T>> m_data;
+    std::vector<uint32_t> m_free_list;
+    std::vector<uint32_t> m_generation;
+
+    std::vector<uint32_t> m_dense;
+    std::vector<uint32_t> m_dense_index;
+
+public:
+    struct Handle {
+        uint32_t index;
+        uint32_t generation;
+
+        uint64_t value() const noexcept {
+            return (uint64_t(index) << 32) | generation;
+        }
+
+        bool operator==(const Handle&) const = default;
+
+        struct Hash {
+            size_t operator()(const Handle& h) const noexcept {
+                return h.value();
+            }
+        };
+    };
+
+    using value_type = T;
+    using reference = T&;
+    using const_reference = const T&;
+    using pointer = T*;
+
+    using size_type = size_t;
+
+    class iterator { // NOLINT
+    private:
+        SparseVector* m_owner;
+        size_t m_index;
+
+    public:
+        using iterator_category = std::random_access_iterator_tag;
+        using iterator_concept = std::random_access_iterator_tag;
+        using value_type = T;
+        using difference_type = std::ptrdiff_t;
+        using pointer = T*;
+        using reference = T&;
+
+        iterator(SparseVector* owner, size_t index)
+            : m_owner(owner), m_index(index) {}
+
+        reference operator*() {
+            return m_owner->m_data[m_owner->m_dense[m_index]].value();
+        }
+
+        pointer operator->() { return &(**this); }
+
+        iterator& operator++() {
+            ++m_index;
+            return *this;
+        }
+
+        iterator operator++(int) {
+            iterator tmp = *this;
+            ++(*this);
+            return tmp;
+        }
+
+        iterator& operator--() {
+            --m_index;
+            return *this;
+        }
+
+        iterator operator--(int) {
+            iterator tmp = *this;
+            --(*this);
+            return tmp;
+        }
+
+        bool operator==(const iterator& other) const {
+            return m_owner == other.m_owner && m_index == other.m_index;
+        }
+
+        bool operator!=(const iterator& other) const {
+            return !(*this == other);
+        }
+
+        iterator operator+(difference_type n) const {
+            return iterator(m_owner, m_index + n);
+        }
+
+        iterator operator-(difference_type n) const {
+            return iterator(m_owner, m_index - n);
+        }
+
+        difference_type operator-(const iterator& other) const {
+            return static_cast<difference_type>(m_index) -
+                   static_cast<difference_type>(other.m_index);
+        }
+
+        iterator& operator+=(difference_type n) {
+            m_index += n;
+            return *this;
+        }
+
+        iterator& operator-=(difference_type n) {
+            m_index -= n;
+            return *this;
+        }
+
+        reference operator[](difference_type n) const { return *(*this + n); }
+
+        bool operator<(const iterator& other) const {
+            return m_index < other.m_index;
+        }
+
+        bool operator>(const iterator& other) const {
+            return m_index > other.m_index;
+        }
+
+        bool operator<=(const iterator& other) const {
+            return m_index <= other.m_index;
+        }
+
+        bool operator>=(const iterator& other) const {
+            return m_index >= other.m_index;
+        }
+        friend iterator operator+(difference_type n, const iterator& it) {
+            return it + n;
+        }
+    };
+
+    class const_iterator { // NOLINT
+    private:
+        const SparseVector* m_owner;
+        size_t m_index;
+
+    public:
+        using iterator_category = std::random_access_iterator_tag;
+        using iterator_concept = std::random_access_iterator_tag;
+        using value_type = T;
+        using difference_type = std::ptrdiff_t;
+        using pointer = const T*;
+        using reference = const T&;
+
+        const_iterator(const SparseVector* owner, size_t index)
+            : m_owner(owner), m_index(index) {}
+
+        reference operator*() const {
+            return m_owner->m_data[m_owner->m_dense[m_index]].value();
+        }
+
+        pointer operator->() const { return &(**this); }
+
+        const_iterator& operator++() {
+            ++m_index;
+            return *this;
+        }
+
+        const_iterator operator++(int) {
+            const_iterator tmp = *this;
+            ++(*this);
+            return tmp;
+        }
+
+        const_iterator& operator--() {
+            --m_index;
+            return *this;
+        }
+
+        const_iterator operator--(int) {
+            const_iterator tmp = *this;
+            --(*this);
+            return tmp;
+        }
+
+        bool operator==(const const_iterator& other) const {
+            return m_owner == other.m_owner && m_index == other.m_index;
+        }
+
+        bool operator!=(const const_iterator& other) const {
+            return !(*this == other);
+        }
+
+        const_iterator operator+(difference_type n) const {
+            return const_iterator(m_owner, m_index + n);
+        }
+
+        const_iterator operator-(difference_type n) const {
+            return const_iterator(m_owner, m_index - n);
+        }
+
+        difference_type operator-(const const_iterator& other) const {
+            return static_cast<difference_type>(m_index) -
+                   static_cast<difference_type>(other.m_index);
+        }
+
+        const_iterator& operator+=(difference_type n) {
+            m_index += n;
+            return *this;
+        }
+
+        const_iterator& operator-=(difference_type n) {
+            m_index -= n;
+            return *this;
+        }
+
+        reference operator[](difference_type n) const { return *(*this + n); }
+
+        bool operator<(const const_iterator& other) const {
+            return m_index < other.m_index;
+        }
+
+        bool operator>(const const_iterator& other) const {
+            return m_index > other.m_index;
+        }
+
+        bool operator<=(const const_iterator& other) const {
+            return m_index <= other.m_index;
+        }
+
+        bool operator>=(const const_iterator& other) const {
+            return m_index >= other.m_index;
+        }
+        friend const_iterator operator+(difference_type n,
+                                        const const_iterator& it) {
+            return it + n;
+        }
+    };
+
+    template <class U> [[nodiscard]] Handle insert(U&& value) {
+        uint32_t id;
+        if (!m_free_list.empty()) {
+            id = m_free_list.back();
+            m_free_list.pop_back();
+            m_data[id].emplace(std::forward<U>(value));
+
+            m_dense_index[id] = m_dense.size();
+        } else {
+            id = m_data.size();
+            m_data.push_back(std::forward<U>(value));
+            m_generation.push_back(1);
+            m_dense_index.emplace_back(m_dense.size());
+        }
+
+        m_dense.push_back(id);
+        return {id, m_generation[id]};
+    }
+
+    template <typename... Args> Handle emplace(Args&&... args) {
+        return insert(T(std::forward<Args>(args)...));
+    }
+
+    void erase(Handle h) {
+
+        if (!exists(h)) {
+            return;
+        }
+        uint32_t id = h.index;
+        m_free_list.push_back(id);
+        uint32_t index = m_dense_index[id];
+        uint32_t last_id = m_dense.back();
+        m_dense[index] = last_id;
+        m_dense_index[last_id] = index;
+
+        m_dense.pop_back();
+        m_data[id].reset();
+        ++m_generation[id];
+    }
+
+    T& operator[](Handle h) {
+        assert(exists(h));
+        return m_data[h.index].value();
+    }
+
+    const T& operator[](Handle h) const {
+        assert(exists(h));
+        return m_data[h.index].value();
+    }
+
+    bool exists(Handle h) const {
+        return h.index < m_generation.size() &&
+               m_generation[h.index] == h.generation;
+    }
+
+    void reserve(size_t n) {
+        m_data.reserve(n);
+        m_generation.reserve(n);
+        m_dense.reserve(n);
+        m_dense_index.reserve(n);
+    }
+
+    size_t size() const { return m_dense.size(); }
+
+    bool empty() const { return m_dense.empty(); }
+
+    iterator begin() { return iterator(this, 0); }
+
+    iterator end() { return iterator(this, m_dense.size()); }
+
+    const_iterator begin() const { return const_iterator(this, 0); }
+
+    const_iterator end() const { return const_iterator(this, m_dense.size()); }
+
+    const_iterator cbegin() const { return begin(); }
+
+    const_iterator cend() const { return end(); }
+};
+
+} // namespace Cubed

include/Cubed/tools/toml.utils.hpp

@@ -29,6 +29,12 @@ std::optional<T> safe_get_value(const toml::table& table, std::string_view key,
     return value;
 }
 
+inline std::optional<std::string>
+safe_get_value(const toml::table& table, std::string_view key,
+               std::string_view default_value) {
+    return safe_get_value(table, key, std::string(default_value));
+}
+
 } // namespace TOML
 
 } // namespace Cubed

include/Cubed/ui/anchor.hpp

@@ -12,4 +12,7 @@ enum class Anchor {
     BOTTOM_LEFT,
     BOTTOM_CENTER,
     BOTTOM_RIGHT,
+
+    FOLLOW_MOUSE
+
 };

include/Cubed/ui/column_layout.hpp

@@ -12,9 +12,6 @@ public:
     ColumnLayout& operator=(ColumnLayout&&) = delete;
     ColumnLayout(Widget* parent);
     ~ColumnLayout();
-
-    void update(float dt) override;
-
     float width() const override;
     float height() const override;
 
@@ -29,5 +26,7 @@ private:
     float m_content_height = 0.0f;
     float m_content_width = 0.0f;
     ColumnLayoutAnchor m_layout_anchor = ColumnLayoutAnchor::CENTER;
+
+    void on_update(float dt) override;
 };
 } // namespace Cubed

include/Cubed/ui/image.hpp

@@ -13,13 +13,19 @@ public:
     Image& operator=(const Image&) = delete;
     Image& operator=(Image&&) = delete;
     Image(Widget* parent);
-
-    Image& set_image(const std::string& path, TextureManager& texture_manager);
+    // If you need to set width and height to the material's size, pass true,
+    // If you set fill parent, please pass false.
+    Image& set_image(const std::string& path, TextureManager& texture_manager,
+                     bool change_size);
+    // If you need to set width and height to the material's size, pass true
+    // If you set fill parent, please pass false.
+    Image& set_texture(const Texture* texture, bool change_size);
     float width() const override;
     float height() const override;
     const Texture* texture() const;
     Image& set_scale(float scale);
     float scale() const;
+    bool has_texture() const;
 
 private:
     void on_render(Renderer& renderer) override;

include/Cubed/ui/inventory_ui.hpp

@@ -0,0 +1,30 @@
+#pragma once
+
+#include "Cubed/ui/item_slot.hpp"
+#include "Cubed/ui/label.hpp"
+#include "Cubed/ui/ui_manager.hpp"
+namespace Cubed {
+class WorldScene;
+class InventoryUI : public UIManager {
+public:
+    InventoryUI(WorldScene& m_scene);
+
+    void init() override;
+    void on_re_enter();
+    void update(float dt) override;
+
+private:
+    WorldScene& m_scene;
+    std::vector<ItemSlot*> m_slots;
+    std::vector<ItemSlot*> m_hotbar;
+    Label* m_item_info = nullptr;
+
+    Image* m_selected_image = nullptr;
+    BlockType m_selected_block = 0;
+    void update_item_info();
+    bool handle_mouse_button_event(const MouseButtonEvent& e) override;
+
+    ItemSlot* get_hovered_slot();
+    std::pair<ItemSlot*, size_t> get_hovered_hotbar_slot();
+};
+} // namespace Cubed

include/Cubed/ui/item_slot.hpp

@@ -0,0 +1,33 @@
+#pragma once
+
+#include "Cubed/gameplay/block.hpp"
+#include "Cubed/ui/image.hpp"
+#include "Cubed/ui/widget.hpp"
+namespace Cubed {
+class TextureManager;
+class ItemSlot : public Widget {
+public:
+    static constexpr float DEFAULT_WIDTH = 16.0f;
+    static constexpr float DEFAULT_HEIGHT = 16.0f;
+    ItemSlot(Widget* parent);
+
+    ItemSlot& set_default_background(TextureManager& m_texture_manager);
+    ItemSlot& set_scale(float m_scale);
+    ItemSlot& set_item(BlockType id, const Texture* texture);
+    float width() const override;
+    float height() const override;
+    bool handle_mouse_move_event(const MouseMoveEvent& e) override;
+    BlockType block() const;
+    bool hovered() const;
+
+private:
+    static constexpr const char* DEFAULT_SLOT_PATH = "texture/ui/slot.png";
+    void on_render(Renderer& renderer) override;
+    void on_update(float dt) override;
+    std::unique_ptr<Image> m_background;
+    std::unique_ptr<Image> m_foreground;
+    BlockType m_block_type;
+    float m_scale = 1.0f;
+    bool m_hovered = false;
+};
+} // namespace Cubed

include/Cubed/ui/rect.hpp

@@ -21,6 +21,7 @@ public:
     Rect& set_alpha(float alpha);
 
     Color color() const;
+    virtual bool supports_border() const override;
 
 private:
     void on_update(float dt) override;

include/Cubed/ui/row_layout.hpp

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "Cubed/ui/widget.hpp"
+namespace Cubed {
+class RowLayout : public Widget {
+public:
+    RowLayout(Widget* parent);
+    ~RowLayout();
+    float width() const override;
+    float height() const override;
+
+    RowLayout& set_spacing(int spacing);
+
+    void layout();
+
+private:
+    int m_spacing = 0;
+    float m_content_height = 0.0f;
+    float m_content_width = 0.0f;
+    void on_update(float dt) override;
+};
+} // namespace Cubed

include/Cubed/ui/widget.hpp

@@ -2,9 +2,11 @@
 #include "Cubed/input/event.hpp"
 #include "Cubed/ui/anchor.hpp"
 
+#include <array>
 #include <glm/glm.hpp>
 #include <memory>
 #include <vector>
+
 namespace Cubed {
 class Renderer;
 
@@ -31,7 +33,7 @@ public:
     virtual void render(Renderer& renderer);
     virtual Widget& set_anchor(Anchor anchor);
     virtual Widget& set_offset(glm::ivec2 offset);
-    virtual Widget& set_window_size(int width, int height);
+    static void set_window_size(int width, int height);
     virtual Widget& set_visible(bool visible);
     // Returns the final display size
 
@@ -43,7 +45,9 @@ public:
     virtual Widget& set_fill_parent(bool fill);
     virtual Widget& set_fill_width(bool fill);
     virtual Widget& set_fill_height(bool fill);
-
+    virtual Widget& set_border_size(int size);
+    virtual Widget& set_border_visale(bool visable);
+    virtual bool supports_border() const;
     virtual glm::vec2 pos() const;
 
     virtual bool handle_key_event(const KeyEvent& e);
@@ -63,16 +67,17 @@ public:
 
 protected:
     Widget* m_parent = nullptr;
-    float m_window_height = 0.0f;
-    float m_window_width = 0.0f;
-    float m_width = 0.0f;
-    float m_height = 0.0f;
+    static inline float m_window_height = 0.0f;
+    static inline float m_window_width = 0.0f;
+
     // Center is at the top-left corner, position is at the top-left corner
     Anchor m_anchor = Anchor::TOP_LEFT;
     bool m_visible = true;
     bool m_fill_parent = false;
     bool m_fill_height = false;
     bool m_fill_width = false;
+    bool m_show_border = false;
+    int m_border_size = 5;
     glm::ivec2 m_offset{0, 0};
 
     std::vector<std::unique_ptr<Widget>>& children();
@@ -82,9 +87,22 @@ protected:
     virtual void on_update(float dt);
     virtual void on_render(Renderer& renderer);
     virtual glm::vec2 compute_position() const;
+    virtual void update_border();
+    void set_width_internal(float width);
+    void set_height_internal(float height);
 
 private:
     std::vector<std::unique_ptr<Widget>> m_children;
+    /*
+    0 - up
+    1 - down
+    2 - left
+    3 - right
+    */
+    std::array<std::unique_ptr<Widget>, 4> m_border;
     TraversalOrder m_order = TraversalOrder::BACK_TO_FRONT;
+    glm::vec2 m_mouse_pos;
+    float m_width = 0.0f;
+    float m_height = 0.0f;
 };
 } // namespace Cubed

include/Cubed/ui/world_ui_manager.hpp

@@ -2,6 +2,8 @@
 
 #include "Cubed/ui/chat_box.hpp"
 #include "Cubed/ui/image.hpp"
+#include "Cubed/ui/item_slot.hpp"
+#include "Cubed/ui/row_layout.hpp"
 #include "Cubed/ui/ui_manager.hpp"
 #include "Cubed/ui/widget.hpp"
 
@@ -26,10 +28,14 @@ public:
 
 private:
     bool handle_key_event(const KeyEvent& e) override;
+    void update_hotbar();
     WorldScene& m_scene;
 
     ChatBox* m_chat_box = nullptr;
     Image* m_mircophone = nullptr;
     Label* m_disbable_voice = nullptr;
+    RowLayout* m_hotbar = nullptr;
+
+    std::vector<ItemSlot*> m_hotbar_slot;
 };
 } // namespace Cubed

include/entt/config/config.h

@@ -0,0 +1,134 @@
+#ifndef ENTT_CONFIG_CONFIG_H
+#define ENTT_CONFIG_CONFIG_H
+
+#if __has_include(<entt/ext/config.h>)
+#    include <entt/ext/config.h>
+#endif
+
+#include <version>
+#include "version.h"
+
+// NOLINTBEGIN(cppcoreguidelines-macro-usage)
+
+#ifdef ENTT_USE_STL
+#    define ENTT_FORCE_STL
+#endif
+
+#if defined(__cpp_exceptions) && !defined(ENTT_NO_EXCEPTION)
+#    define ENTT_THROW throw
+#    define ENTT_TRY try
+#    define ENTT_CATCH catch(...)
+#else
+#    define ENTT_THROW
+#    define ENTT_TRY if(true)
+#    define ENTT_CATCH if(false)
+#endif
+
+#if defined(__cpp_consteval)
+#    define ENTT_CONSTEVAL consteval
+#else
+#    define ENTT_CONSTEVAL constexpr
+#endif
+
+#ifdef ENTT_USE_ATOMIC
+#    include "../stl/atomic.hpp"
+#    define ENTT_MAYBE_ATOMIC(Type) stl::atomic<Type>
+#else
+#    define ENTT_MAYBE_ATOMIC(Type) Type
+#endif
+
+#ifndef ENTT_ID_TYPE
+#    include "../stl/cstdint.hpp"
+#    define ENTT_ID_TYPE stl::uint32_t
+#else
+#    include "../stl/cstdint.hpp" // provides coverage for types in the std namespace
+#endif
+
+#ifndef ENTT_SPARSE_PAGE
+#    define ENTT_SPARSE_PAGE 4096
+#endif
+
+#ifndef ENTT_PACKED_PAGE
+#    define ENTT_PACKED_PAGE 1024
+#endif
+
+#ifdef ENTT_DISABLE_ASSERT
+#    undef ENTT_ASSERT
+#    define ENTT_ASSERT(condition, msg) (void(0))
+#elif !defined ENTT_ASSERT
+#    include <cassert>
+#    define ENTT_ASSERT(condition, msg) assert(((condition) && (msg)))
+#endif
+
+#ifdef ENTT_DISABLE_ASSERT
+#    undef ENTT_ASSERT_CONSTEXPR
+#    define ENTT_ASSERT_CONSTEXPR(condition, msg) (void(0))
+#elif !defined ENTT_ASSERT_CONSTEXPR
+#    define ENTT_ASSERT_CONSTEXPR(condition, msg) ENTT_ASSERT(condition, msg)
+#endif
+
+#define ENTT_FAIL(msg) ENTT_ASSERT(false, msg);
+
+#ifdef ENTT_NO_ETO
+#    define ENTT_ETO_TYPE(Type) void
+#else
+#    define ENTT_ETO_TYPE(Type) Type
+#endif
+
+#ifdef ENTT_NO_MIXIN
+#    define ENTT_STORAGE(Mixin, ...) __VA_ARGS__
+#else
+#    define ENTT_STORAGE(Mixin, ...) Mixin<__VA_ARGS__>
+#endif
+
+#ifdef ENTT_STANDARD_CPP
+#    define ENTT_NONSTD false
+#else
+#    define ENTT_NONSTD true
+#    if defined __clang__ || defined __GNUC__
+#        define ENTT_PRETTY_FUNCTION __PRETTY_FUNCTION__
+#        define ENTT_PRETTY_FUNCTION_PREFIX '='
+#        define ENTT_PRETTY_FUNCTION_SUFFIX ']'
+#    elif defined _MSC_VER
+#        define ENTT_PRETTY_FUNCTION __FUNCSIG__
+#        define ENTT_PRETTY_FUNCTION_PREFIX '<'
+#        define ENTT_PRETTY_FUNCTION_SUFFIX '>'
+#    endif
+#endif
+
+#ifndef ENTT_EXPORT
+#    if defined _WIN32 || defined __CYGWIN__ || defined _MSC_VER
+#        define ENTT_EXPORT __declspec(dllexport)
+#        define ENTT_IMPORT __declspec(dllimport)
+#        define ENTT_HIDDEN
+#    elif defined __GNUC__ && __GNUC__ >= 4
+#        define ENTT_EXPORT __attribute__((visibility("default")))
+#        define ENTT_IMPORT __attribute__((visibility("default")))
+#        define ENTT_HIDDEN __attribute__((visibility("hidden")))
+#    else /* Unsupported compiler */
+#        define ENTT_EXPORT
+#        define ENTT_IMPORT
+#        define ENTT_HIDDEN
+#    endif
+#endif
+
+#ifndef ENTT_API
+#    if defined ENTT_API_EXPORT
+#        define ENTT_API ENTT_EXPORT
+#    elif defined ENTT_API_IMPORT
+#        define ENTT_API ENTT_IMPORT
+#    else /* No API */
+#        define ENTT_API
+#    endif
+#endif
+
+#if defined _MSC_VER
+#    pragma detect_mismatch("entt.version", ENTT_VERSION)
+#    pragma detect_mismatch("entt.noexcept", ENTT_XSTR(ENTT_TRY))
+#    pragma detect_mismatch("entt.id", ENTT_XSTR(ENTT_ID_TYPE))
+#    pragma detect_mismatch("entt.nonstd", ENTT_XSTR(ENTT_NONSTD))
+#endif
+
+// NOLINTEND(cppcoreguidelines-macro-usage)
+
+#endif

include/entt/config/macro.h

@@ -0,0 +1,11 @@
+#ifndef ENTT_CONFIG_MACRO_H
+#define ENTT_CONFIG_MACRO_H
+
+// NOLINTBEGIN(cppcoreguidelines-macro-usage)
+
+#define ENTT_STR(arg) #arg
+#define ENTT_XSTR(arg) ENTT_STR(arg)
+
+// NOLINTEND(cppcoreguidelines-macro-usage)
+
+#endif

include/entt/config/version.h

@@ -0,0 +1,18 @@
+#ifndef ENTT_CONFIG_VERSION_H
+#define ENTT_CONFIG_VERSION_H
+
+#include "macro.h"
+
+// NOLINTBEGIN(cppcoreguidelines-macro-*,modernize-macro-*)
+
+#define ENTT_VERSION_MAJOR 4
+#define ENTT_VERSION_MINOR 0
+#define ENTT_VERSION_PATCH 0
+
+#define ENTT_VERSION \
+    ENTT_XSTR(ENTT_VERSION_MAJOR) \
+    "." ENTT_XSTR(ENTT_VERSION_MINOR) "." ENTT_XSTR(ENTT_VERSION_PATCH)
+
+// NOLINTEND(cppcoreguidelines-macro-*,modernize-macro-*)
+
+#endif

include/entt/container/dense_set.hpp

@@ -0,0 +1,890 @@
+#ifndef ENTT_CONTAINER_DENSE_SET_HPP
+#define ENTT_CONTAINER_DENSE_SET_HPP
+
+#include <compare>
+#include "../config/config.h"
+#include "../core/bit.hpp"
+#include "../core/compressed_pair.hpp"
+#include "../core/type_traits.hpp"
+#include "../stl/bit.hpp"
+#include "../stl/cmath.hpp"
+#include "../stl/concepts.hpp"
+#include "../stl/cstddef.hpp"
+#include "../stl/functional.hpp"
+#include "../stl/iterator.hpp"
+#include "../stl/limits.hpp"
+#include "../stl/memory.hpp"
+#include "../stl/tuple.hpp"
+#include "../stl/type_traits.hpp"
+#include "../stl/utility.hpp"
+#include "../stl/vector.hpp"
+#include "fwd.hpp"
+
+namespace entt {
+
+/*! @cond ENTT_INTERNAL */
+namespace internal {
+
+static constexpr stl::size_t dense_set_placeholder_position = (stl::numeric_limits<stl::size_t>::max)();
+
+template<typename It>
+class dense_set_iterator final {
+    template<typename>
+    friend class dense_set_iterator;
+
+    static_assert(stl::is_pointer_v<It>, "Not a pointer type");
+
+public:
+    using value_type = stl::remove_const_t<stl::remove_pointer_t<It>>::second_type;
+    using pointer = const value_type *;
+    using reference = const value_type &;
+    using difference_type = stl::ptrdiff_t;
+    using iterator_category = stl::random_access_iterator_tag;
+
+    constexpr dense_set_iterator() noexcept
+        : it{} {}
+
+    constexpr dense_set_iterator(const It iter) noexcept
+        : it{iter} {}
+
+    template<typename Other>
+    requires (!stl::same_as<It, Other> && stl::constructible_from<It, Other>)
+    constexpr dense_set_iterator(const dense_set_iterator<Other> &other) noexcept
+        : it{other.it} {}
+
+    constexpr dense_set_iterator &operator++() noexcept {
+        return ++it, *this;
+    }
+
+    constexpr dense_set_iterator operator++(int) noexcept {
+        const dense_set_iterator orig = *this;
+        return ++(*this), orig;
+    }
+
+    constexpr dense_set_iterator &operator--() noexcept {
+        return --it, *this;
+    }
+
+    constexpr dense_set_iterator operator--(int) noexcept {
+        const dense_set_iterator orig = *this;
+        return operator--(), orig;
+    }
+
+    constexpr dense_set_iterator &operator+=(const difference_type value) noexcept {
+        it += value;
+        return *this;
+    }
+
+    constexpr dense_set_iterator operator+(const difference_type value) const noexcept {
+        dense_set_iterator copy = *this;
+        return (copy += value);
+    }
+
+    constexpr dense_set_iterator &operator-=(const difference_type value) noexcept {
+        return (*this += -value);
+    }
+
+    constexpr dense_set_iterator operator-(const difference_type value) const noexcept {
+        return (*this + -value);
+    }
+
+    [[nodiscard]] constexpr reference operator[](const difference_type value) const noexcept {
+        return it[value].second;
+    }
+
+    [[nodiscard]] constexpr pointer operator->() const noexcept {
+        return stl::addressof(operator[](0));
+    }
+
+    [[nodiscard]] constexpr reference operator*() const noexcept {
+        return operator[](0);
+    }
+
+    template<typename Other>
+    [[nodiscard]] constexpr stl::ptrdiff_t operator-(const dense_set_iterator<Other> &other) const noexcept {
+        return it - other.it;
+    }
+
+    template<typename Other>
+    [[nodiscard]] constexpr bool operator==(const dense_set_iterator<Other> &other) const noexcept {
+        return it == other.it;
+    }
+
+    template<typename Other>
+    [[nodiscard]] constexpr auto operator<=>(const dense_set_iterator<Other> &other) const noexcept {
+        return it <=> other.it;
+    }
+
+private:
+    It it;
+};
+
+template<typename It>
+class dense_set_local_iterator final {
+    template<typename>
+    friend class dense_set_local_iterator;
+
+    static_assert(stl::is_pointer_v<It>, "Not a pointer type");
+
+public:
+    using value_type = stl::remove_const_t<stl::remove_pointer_t<It>>::second_type;
+    using pointer = const value_type *;
+    using reference = const value_type &;
+    using difference_type = stl::ptrdiff_t;
+    using iterator_category = stl::forward_iterator_tag;
+
+    constexpr dense_set_local_iterator() noexcept = default;
+
+    constexpr dense_set_local_iterator(It iter, const stl::size_t pos) noexcept
+        : it{iter},
+          offset{pos} {}
+
+    template<typename Other>
+    requires (!stl::same_as<It, Other> && stl::constructible_from<It, Other>)
+    constexpr dense_set_local_iterator(const dense_set_local_iterator<Other> &other) noexcept
+        : it{other.it},
+          offset{other.offset} {}
+
+    constexpr dense_set_local_iterator &operator++() noexcept {
+        return offset = it[static_cast<difference_type>(offset)].first, *this;
+    }
+
+    constexpr dense_set_local_iterator operator++(int) noexcept {
+        const dense_set_local_iterator orig = *this;
+        return ++(*this), orig;
+    }
+
+    [[nodiscard]] constexpr pointer operator->() const noexcept {
+        return stl::addressof(it[static_cast<difference_type>(offset)].second);
+    }
+
+    [[nodiscard]] constexpr reference operator*() const noexcept {
+        return *operator->();
+    }
+
+    template<typename Other>
+    [[nodiscard]] constexpr bool operator==(const dense_set_local_iterator<Other> &other) const noexcept {
+        return offset == other.offset;
+    }
+
+    [[nodiscard]] constexpr stl::size_t index() const noexcept {
+        return offset;
+    }
+
+private:
+    It it{};
+    stl::size_t offset{dense_set_placeholder_position};
+};
+
+} // namespace internal
+/*! @endcond */
+
+/**
+ * @brief Associative container for unique objects of a given type.
+ *
+ * Internally, elements are organized into buckets. Which bucket an element is
+ * placed into depends entirely on its hash. Elements with the same hash code
+ * appear in the same bucket.
+ *
+ * @tparam Type Value type of the associative container.
+ * @tparam Hash Type of function to use to hash the values.
+ * @tparam KeyEqual Type of function to use to compare the values for equality.
+ * @tparam Allocator Type of allocator used to manage memory and elements.
+ */
+template<typename Type, typename Hash, typename KeyEqual, typename Allocator>
+class dense_set {
+    static constexpr float default_threshold = 0.875f;
+    static constexpr stl::size_t minimum_capacity = 8u;
+    static constexpr stl::size_t placeholder_position = internal::dense_set_placeholder_position;
+
+    using node_type = stl::pair<stl::size_t, Type>;
+    using alloc_traits = stl::allocator_traits<Allocator>;
+    static_assert(stl::is_same_v<typename alloc_traits::value_type, Type>, "Invalid value type");
+    using sparse_container_type = stl::vector<stl::size_t, typename alloc_traits::template rebind_alloc<stl::size_t>>;
+    using packed_container_type = stl::vector<node_type, typename alloc_traits::template rebind_alloc<node_type>>;
+
+    [[nodiscard]] stl::size_t value_to_bucket(const auto &value) const noexcept {
+        return fast_mod(static_cast<size_type>(sparse.second()(value)), bucket_count());
+    }
+
+    [[nodiscard]] auto constrained_find(const auto &value, const stl::size_t bucket) {
+        for(auto offset = sparse.first()[bucket]; offset != placeholder_position; offset = packed.first()[offset].first) {
+            if(packed.second()(packed.first()[offset].second, value)) {
+                return begin() + static_cast<iterator::difference_type>(offset);
+            }
+        }
+
+        return end();
+    }
+
+    [[nodiscard]] auto constrained_find(const auto &value, const stl::size_t bucket) const {
+        for(auto offset = sparse.first()[bucket]; offset != placeholder_position; offset = packed.first()[offset].first) {
+            if(packed.second()(packed.first()[offset].second, value)) {
+                return cbegin() + static_cast<const_iterator::difference_type>(offset);
+            }
+        }
+
+        return cend();
+    }
+
+    template<typename Other>
+    [[nodiscard]] auto insert_or_do_nothing(Other &&value) {
+        const auto index = value_to_bucket(value);
+
+        if(auto it = constrained_find(value, index); it != end()) {
+            return stl::make_pair(it, false);
+        }
+
+        packed.first().emplace_back(sparse.first()[index], stl::forward<Other>(value));
+        sparse.first()[index] = packed.first().size() - 1u;
+        rehash_if_required();
+
+        return stl::make_pair(--end(), true);
+    }
+
+    void move_and_pop(const stl::size_t pos) {
+        if(const auto last = size() - 1u; pos != last) {
+            size_type *curr = &sparse.first()[value_to_bucket(packed.first().back().second)];
+            packed.first()[pos] = stl::move(packed.first().back());
+            for(; *curr != last; curr = &packed.first()[*curr].first) {}
+            *curr = pos;
+        }
+
+        packed.first().pop_back();
+    }
+
+    void rehash_if_required() {
+        if(const auto bc = bucket_count(); size() > static_cast<size_type>(static_cast<float>(bc) * max_load_factor())) {
+            rehash(bc * 2u);
+        }
+    }
+
+public:
+    /*! @brief Allocator type. */
+    using allocator_type = Allocator;
+    /*! @brief Key type of the container. */
+    using key_type = Type;
+    /*! @brief Value type of the container. */
+    using value_type = Type;
+    /*! @brief Unsigned integer type. */
+    using size_type = stl::size_t;
+    /*! @brief Signed integer type. */
+    using difference_type = stl::ptrdiff_t;
+    /*! @brief Type of function to use to hash the elements. */
+    using hasher = Hash;
+    /*! @brief Type of function to use to compare the elements for equality. */
+    using key_equal = KeyEqual;
+    /*! @brief Random access iterator type. */
+    using iterator = internal::dense_set_iterator<typename packed_container_type::pointer>;
+    /*! @brief Constant random access iterator type. */
+    using const_iterator = internal::dense_set_iterator<typename packed_container_type::const_pointer>;
+    /*! @brief Reverse iterator type. */
+    using reverse_iterator = stl::reverse_iterator<iterator>;
+    /*! @brief Constant reverse iterator type. */
+    using const_reverse_iterator = stl::reverse_iterator<const_iterator>;
+    /*! @brief Forward iterator type. */
+    using local_iterator = internal::dense_set_local_iterator<typename packed_container_type::pointer>;
+    /*! @brief Constant forward iterator type. */
+    using const_local_iterator = internal::dense_set_local_iterator<typename packed_container_type::const_pointer>;
+
+    /*! @brief Default constructor. */
+    dense_set()
+        : dense_set{minimum_capacity} {}
+
+    /**
+     * @brief Constructs an empty container with a given allocator.
+     * @param allocator The allocator to use.
+     */
+    explicit dense_set(const allocator_type &allocator)
+        : dense_set{minimum_capacity, hasher{}, key_equal{}, allocator} {}
+
+    /**
+     * @brief Constructs an empty container with a given allocator and user
+     * supplied minimal number of buckets.
+     * @param cnt Minimal number of buckets.
+     * @param allocator The allocator to use.
+     */
+    dense_set(const size_type cnt, const allocator_type &allocator)
+        : dense_set{cnt, hasher{}, key_equal{}, allocator} {}
+
+    /**
+     * @brief Constructs an empty container with a given allocator, hash
+     * function and user supplied minimal number of buckets.
+     * @param cnt Minimal number of buckets.
+     * @param hash Hash function to use.
+     * @param allocator The allocator to use.
+     */
+    dense_set(const size_type cnt, const hasher &hash, const allocator_type &allocator)
+        : dense_set{cnt, hash, key_equal{}, allocator} {}
+
+    /**
+     * @brief Constructs an empty container with a given allocator, hash
+     * function, compare function and user supplied minimal number of buckets.
+     * @param cnt Minimal number of buckets.
+     * @param hash Hash function to use.
+     * @param equal Compare function to use.
+     * @param allocator The allocator to use.
+     */
+    explicit dense_set(const size_type cnt, const hasher &hash = hasher{}, const key_equal &equal = key_equal{}, const allocator_type &allocator = allocator_type{})
+        : sparse{allocator, hash},
+          packed{allocator, equal} {
+        rehash(cnt);
+    }
+
+    /*! @brief Default copy constructor. */
+    dense_set(const dense_set &) = default;
+
+    /**
+     * @brief Allocator-extended copy constructor.
+     * @param other The instance to copy from.
+     * @param allocator The allocator to use.
+     */
+    dense_set(const dense_set &other, const allocator_type &allocator)
+        : sparse{stl::piecewise_construct, stl::forward_as_tuple(other.sparse.first(), allocator), stl::forward_as_tuple(other.sparse.second())},
+          packed{stl::piecewise_construct, stl::forward_as_tuple(other.packed.first(), allocator), stl::forward_as_tuple(other.packed.second())},
+          threshold{other.threshold} {}
+
+    /*! @brief Default move constructor. */
+    dense_set(dense_set &&) noexcept = default;
+
+    /**
+     * @brief Allocator-extended move constructor.
+     * @param other The instance to move from.
+     * @param allocator The allocator to use.
+     */
+    dense_set(dense_set &&other, const allocator_type &allocator)
+        : sparse{stl::piecewise_construct, stl::forward_as_tuple(stl::move(other.sparse.first()), allocator), stl::forward_as_tuple(stl::move(other.sparse.second()))},
+          packed{stl::piecewise_construct, stl::forward_as_tuple(stl::move(other.packed.first()), allocator), stl::forward_as_tuple(stl::move(other.packed.second()))},
+          threshold{other.threshold} {}
+
+    /*! @brief Default destructor. */
+    ~dense_set() = default;
+
+    /**
+     * @brief Default copy assignment operator.
+     * @return This container.
+     */
+    dense_set &operator=(const dense_set &) = default;
+
+    /**
+     * @brief Default move assignment operator.
+     * @return This container.
+     */
+    dense_set &operator=(dense_set &&) noexcept = default;
+
+    /**
+     * @brief Exchanges the contents with those of a given container.
+     * @param other Container to exchange the content with.
+     */
+    void swap(dense_set &other) noexcept {
+        using stl::swap;
+        swap(sparse, other.sparse);
+        swap(packed, other.packed);
+        swap(threshold, other.threshold);
+    }
+
+    /**
+     * @brief Returns the associated allocator.
+     * @return The associated allocator.
+     */
+    [[nodiscard]] constexpr allocator_type get_allocator() const noexcept {
+        return sparse.first().get_allocator();
+    }
+
+    /**
+     * @brief Returns an iterator to the beginning.
+     *
+     * If the array is empty, the returned iterator will be equal to `end()`.
+     *
+     * @return An iterator to the first instance of the internal array.
+     */
+    [[nodiscard]] const_iterator cbegin() const noexcept {
+        return packed.first().data();
+    }
+
+    /*! @copydoc cbegin */
+    [[nodiscard]] const_iterator begin() const noexcept {
+        return cbegin();
+    }
+
+    /*! @copydoc begin */
+    [[nodiscard]] iterator begin() noexcept {
+        return packed.first().data();
+    }
+
+    /**
+     * @brief Returns an iterator to the end.
+     * @return An iterator to the element following the last instance of the
+     * internal array.
+     */
+    [[nodiscard]] const_iterator cend() const noexcept {
+        return packed.first().data() + packed.first().size();
+    }
+
+    /*! @copydoc cend */
+    [[nodiscard]] const_iterator end() const noexcept {
+        return cend();
+    }
+
+    /*! @copydoc end */
+    [[nodiscard]] iterator end() noexcept {
+        return packed.first().data() + packed.first().size();
+    }
+
+    /**
+     * @brief Returns a reverse iterator to the beginning.
+     *
+     * If the array is empty, the returned iterator will be equal to `rend()`.
+     *
+     * @return An iterator to the first instance of the reversed internal array.
+     */
+    [[nodiscard]] const_reverse_iterator crbegin() const noexcept {
+        return stl::make_reverse_iterator(cend());
+    }
+
+    /*! @copydoc crbegin */
+    [[nodiscard]] const_reverse_iterator rbegin() const noexcept {
+        return crbegin();
+    }
+
+    /*! @copydoc rbegin */
+    [[nodiscard]] reverse_iterator rbegin() noexcept {
+        return stl::make_reverse_iterator(end());
+    }
+
+    /**
+     * @brief Returns a reverse iterator to the end.
+     * @return An iterator to the element following the last instance of the
+     * reversed internal array.
+     */
+    [[nodiscard]] const_reverse_iterator crend() const noexcept {
+        return stl::make_reverse_iterator(cbegin());
+    }
+
+    /*! @copydoc crend */
+    [[nodiscard]] const_reverse_iterator rend() const noexcept {
+        return crend();
+    }
+
+    /*! @copydoc rend */
+    [[nodiscard]] reverse_iterator rend() noexcept {
+        return stl::make_reverse_iterator(begin());
+    }
+
+    /**
+     * @brief Checks whether a container is empty.
+     * @return True if the container is empty, false otherwise.
+     */
+    [[nodiscard]] bool empty() const noexcept {
+        return packed.first().empty();
+    }
+
+    /**
+     * @brief Returns the number of elements in a container.
+     * @return Number of elements in a container.
+     */
+    [[nodiscard]] size_type size() const noexcept {
+        return packed.first().size();
+    }
+
+    /**
+     * @brief Returns the maximum possible number of elements.
+     * @return Maximum possible number of elements.
+     */
+    [[nodiscard]] size_type max_size() const noexcept {
+        return packed.first().max_size();
+    }
+
+    /*! @brief Clears the container. */
+    void clear() noexcept {
+        sparse.first().clear();
+        packed.first().clear();
+        rehash(0u);
+    }
+
+    /**
+     * @brief Inserts an element into the container, if it does not exist.
+     * @param value An element to insert into the container.
+     * @return A pair consisting of an iterator to the inserted element (or to
+     * the element that prevented the insertion) and a bool denoting whether the
+     * insertion took place.
+     */
+    stl::pair<iterator, bool> insert(const value_type &value) {
+        return insert_or_do_nothing(value);
+    }
+
+    /*! @copydoc insert */
+    stl::pair<iterator, bool> insert(value_type &&value) {
+        return insert_or_do_nothing(stl::move(value));
+    }
+
+    /**
+     * @brief Inserts elements into the container, if they do not exist.
+     * @param first An iterator to the first element of the range of elements.
+     * @param last An iterator past the last element of the range of elements.
+     */
+    void insert(stl::input_iterator auto first, stl::input_iterator auto last) {
+        for(; first != last; ++first) {
+            insert(*first);
+        }
+    }
+
+    /**
+     * @brief Constructs an element in-place, if it does not exist.
+     *
+     * The element is also constructed when the container already has the key,
+     * in which case the newly constructed object is destroyed immediately.
+     *
+     * @tparam Args Types of arguments to forward to the constructor of the
+     * element.
+     * @param args Arguments to forward to the constructor of the element.
+     * @return A pair consisting of an iterator to the inserted element (or to
+     * the element that prevented the insertion) and a bool denoting whether the
+     * insertion took place.
+     */
+    template<typename... Args>
+    stl::pair<iterator, bool> emplace(Args &&...args) {
+        if constexpr(((sizeof...(Args) == 1u) && ... && stl::is_same_v<stl::decay_t<Args>, value_type>)) {
+            return insert_or_do_nothing(stl::forward<Args>(args)...);
+        } else {
+            auto &node = packed.first().emplace_back(stl::piecewise_construct, stl::make_tuple(packed.first().size()), stl::forward_as_tuple(stl::forward<Args>(args)...));
+            const auto index = value_to_bucket(node.second);
+
+            if(auto it = constrained_find(node.second, index); it != end()) {
+                packed.first().pop_back();
+                return stl::make_pair(it, false);
+            }
+
+            stl::swap(node.first, sparse.first()[index]);
+            rehash_if_required();
+
+            return stl::make_pair(--end(), true);
+        }
+    }
+
+    /**
+     * @brief Removes an element from a given position.
+     * @param pos An iterator to the element to remove.
+     * @return An iterator following the removed element.
+     */
+    iterator erase(const_iterator pos) {
+        const auto diff = pos - cbegin();
+        erase(*pos);
+        return begin() + diff;
+    }
+
+    /**
+     * @brief Removes the given elements from a container.
+     * @param first An iterator to the first element of the range of elements.
+     * @param last An iterator past the last element of the range of elements.
+     * @return An iterator following the last removed element.
+     */
+    iterator erase(const_iterator first, const_iterator last) {
+        const auto dist = first - cbegin();
+
+        for(auto from = last - cbegin(); from != dist; --from) {
+            erase(packed.first()[static_cast<size_type>(from) - 1u].second);
+        }
+
+        return (begin() + dist);
+    }
+
+    /**
+     * @brief Removes the element associated with a given value.
+     * @param value Value of an element to remove.
+     * @return Number of elements removed (either 0 or 1).
+     */
+    size_type erase(const value_type &value) {
+        for(size_type *curr = &sparse.first()[value_to_bucket(value)]; *curr != placeholder_position; curr = &packed.first()[*curr].first) {
+            if(packed.second()(packed.first()[*curr].second, value)) {
+                const auto index = *curr;
+                *curr = packed.first()[*curr].first;
+                move_and_pop(index);
+                return 1u;
+            }
+        }
+
+        return 0u;
+    }
+
+    /**
+     * @brief Returns the number of elements matching a value (either 1 or 0).
+     * @param key Key value of an element to search for.
+     * @return Number of elements matching the key (either 1 or 0).
+     */
+    [[nodiscard]] size_type count(const value_type &key) const {
+        return find(key) != end();
+    }
+
+    /**
+     * @brief Returns the number of elements matching a key (either 1 or 0).
+     * @param key Key value of an element to search for.
+     * @return Number of elements matching the key (either 1 or 0).
+     */
+    [[nodiscard]] size_type count(const auto &key) const
+    requires is_transparent_v<hasher> && is_transparent_v<key_equal> {
+        return find(key) != end();
+    }
+
+    /**
+     * @brief Finds an element with a given value.
+     * @param value Value of an element to search for.
+     * @return An iterator to an element with the given value. If no such
+     * element is found, a past-the-end iterator is returned.
+     */
+    [[nodiscard]] iterator find(const value_type &value) {
+        return constrained_find(value, value_to_bucket(value));
+    }
+
+    /*! @copydoc find */
+    [[nodiscard]] const_iterator find(const value_type &value) const {
+        return constrained_find(value, value_to_bucket(value));
+    }
+
+    /**
+     * @brief Finds an element that compares _equivalent_ to a given value.
+     * @param value Value of an element to search for.
+     * @return An iterator to an element with the given value. If no such
+     * element is found, a past-the-end iterator is returned.
+     */
+    [[nodiscard]] iterator find(const auto &value)
+    requires is_transparent_v<hasher> && is_transparent_v<key_equal> {
+        return constrained_find(value, value_to_bucket(value));
+    }
+
+    /*! @copydoc find */
+    [[nodiscard]] const_iterator find(const auto &value) const
+    requires is_transparent_v<hasher> && is_transparent_v<key_equal> {
+        return constrained_find(value, value_to_bucket(value));
+    }
+
+    /**
+     * @brief Returns a range containing all elements with a given value.
+     * @param value Value of an element to search for.
+     * @return A pair of iterators pointing to the first element and past the
+     * last element of the range.
+     */
+    [[nodiscard]] stl::pair<iterator, iterator> equal_range(const value_type &value) {
+        const auto it = find(value);
+        return {it, it + !(it == end())};
+    }
+
+    /*! @copydoc equal_range */
+    [[nodiscard]] stl::pair<const_iterator, const_iterator> equal_range(const value_type &value) const {
+        const auto it = find(value);
+        return {it, it + !(it == cend())};
+    }
+
+    /**
+     * @brief Returns a range containing all elements that compare _equivalent_
+     * to a given value.
+     * @param value Value of an element to search for.
+     * @return A pair of iterators pointing to the first element and past the
+     * last element of the range.
+     */
+    [[nodiscard]] stl::pair<iterator, iterator> equal_range(const auto &value)
+    requires is_transparent_v<hasher> && is_transparent_v<key_equal> {
+        const auto it = find(value);
+        return {it, it + !(it == end())};
+    }
+
+    /*! @copydoc equal_range */
+    [[nodiscard]] stl::pair<const_iterator, const_iterator> equal_range(const auto &value) const
+    requires is_transparent_v<hasher> && is_transparent_v<key_equal> {
+        const auto it = find(value);
+        return {it, it + !(it == cend())};
+    }
+
+    /**
+     * @brief Checks if the container contains an element with a given value.
+     * @param value Value of an element to search for.
+     * @return True if there is such an element, false otherwise.
+     */
+    [[nodiscard]] bool contains(const value_type &value) const {
+        return (find(value) != cend());
+    }
+
+    /**
+     * @brief Checks if the container contains an element that compares
+     * _equivalent_ to a given value.
+     * @param value Value of an element to search for.
+     * @return True if there is such an element, false otherwise.
+     */
+    [[nodiscard]] bool contains(const auto &value) const
+    requires is_transparent_v<hasher> && is_transparent_v<key_equal> {
+        return (find(value) != cend());
+    }
+
+    /**
+     * @brief Returns an iterator to the beginning of a given bucket.
+     * @param index An index of a bucket to access.
+     * @return An iterator to the beginning of the given bucket.
+     */
+    [[nodiscard]] const_local_iterator cbegin(const size_type index) const {
+        return {packed.first().data(), sparse.first()[index]};
+    }
+
+    /**
+     * @brief Returns an iterator to the beginning of a given bucket.
+     * @param index An index of a bucket to access.
+     * @return An iterator to the beginning of the given bucket.
+     */
+    [[nodiscard]] const_local_iterator begin(const size_type index) const {
+        return cbegin(index);
+    }
+
+    /**
+     * @brief Returns an iterator to the beginning of a given bucket.
+     * @param index An index of a bucket to access.
+     * @return An iterator to the beginning of the given bucket.
+     */
+    [[nodiscard]] local_iterator begin(const size_type index) {
+        return {packed.first().data(), sparse.first()[index]};
+    }
+
+    /**
+     * @brief Returns an iterator to the end of a given bucket.
+     * @param index An index of a bucket to access.
+     * @return An iterator to the end of the given bucket.
+     */
+    [[nodiscard]] const_local_iterator cend([[maybe_unused]] const size_type index) const {
+        return {};
+    }
+
+    /**
+     * @brief Returns an iterator to the end of a given bucket.
+     * @param index An index of a bucket to access.
+     * @return An iterator to the end of the given bucket.
+     */
+    [[nodiscard]] const_local_iterator end(const size_type index) const {
+        return cend(index);
+    }
+
+    /**
+     * @brief Returns an iterator to the end of a given bucket.
+     * @param index An index of a bucket to access.
+     * @return An iterator to the end of the given bucket.
+     */
+    [[nodiscard]] local_iterator end([[maybe_unused]] const size_type index) {
+        return {};
+    }
+
+    /**
+     * @brief Returns the number of buckets.
+     * @return The number of buckets.
+     */
+    [[nodiscard]] size_type bucket_count() const {
+        return sparse.first().size();
+    }
+
+    /**
+     * @brief Returns the maximum number of buckets.
+     * @return The maximum number of buckets.
+     */
+    [[nodiscard]] size_type max_bucket_count() const {
+        return sparse.first().max_size();
+    }
+
+    /**
+     * @brief Returns the number of elements in a given bucket.
+     * @param index The index of the bucket to examine.
+     * @return The number of elements in the given bucket.
+     */
+    [[nodiscard]] size_type bucket_size(const size_type index) const {
+        return static_cast<size_type>(stl::distance(begin(index), end(index)));
+    }
+
+    /**
+     * @brief Returns the bucket for a given element.
+     * @param value The value of the element to examine.
+     * @return The bucket for the given element.
+     */
+    [[nodiscard]] size_type bucket(const value_type &value) const {
+        return value_to_bucket(value);
+    }
+
+    /**
+     * @brief Returns the average number of elements per bucket.
+     * @return The average number of elements per bucket.
+     */
+    [[nodiscard]] float load_factor() const {
+        return static_cast<float>(size()) / static_cast<float>(bucket_count());
+    }
+
+    /**
+     * @brief Returns the maximum average number of elements per bucket.
+     * @return The maximum average number of elements per bucket.
+     */
+    [[nodiscard]] float max_load_factor() const {
+        return threshold;
+    }
+
+    /**
+     * @brief Sets the desired maximum average number of elements per bucket.
+     * @param value A desired maximum average number of elements per bucket.
+     */
+    void max_load_factor(const float value) {
+        ENTT_ASSERT(value > 0.f, "Invalid load factor");
+        threshold = value;
+        rehash(0u);
+    }
+
+    /**
+     * @brief Reserves at least the specified number of buckets and regenerates
+     * the hash table.
+     * @param cnt New number of buckets.
+     */
+    void rehash(const size_type cnt) {
+        auto value = cnt > minimum_capacity ? cnt : minimum_capacity;
+        const auto cap = static_cast<size_type>(static_cast<float>(size()) / max_load_factor());
+        value = value > cap ? value : cap;
+
+        if(const auto sz = stl::bit_ceil(value); sz != bucket_count()) {
+            sparse.first().resize(sz);
+
+            for(auto &&elem: sparse.first()) {
+                elem = placeholder_position;
+            }
+
+            for(size_type pos{}, last = size(); pos < last; ++pos) {
+                const auto index = value_to_bucket(packed.first()[pos].second);
+                packed.first()[pos].first = stl::exchange(sparse.first()[index], pos);
+            }
+        }
+    }
+
+    /**
+     * @brief Reserves space for at least the specified number of elements and
+     * regenerates the hash table.
+     * @param cnt New number of elements.
+     */
+    void reserve(const size_type cnt) {
+        packed.first().reserve(cnt);
+        rehash(static_cast<size_type>(stl::ceil(static_cast<float>(cnt) / max_load_factor())));
+    }
+
+    /**
+     * @brief Returns the function used to hash the elements.
+     * @return The function used to hash the elements.
+     */
+    [[nodiscard]] hasher hash_function() const {
+        return sparse.second();
+    }
+
+    /**
+     * @brief Returns the function used to compare elements for equality.
+     * @return The function used to compare elements for equality.
+     */
+    [[nodiscard]] key_equal key_eq() const {
+        return packed.second();
+    }
+
+private:
+    compressed_pair<sparse_container_type, hasher> sparse;
+    compressed_pair<packed_container_type, key_equal> packed;
+    float threshold{default_threshold};
+};
+
+} // namespace entt
+
+#endif

include/entt/container/fwd.hpp

@@ -0,0 +1,38 @@
+#ifndef ENTT_CONTAINER_FWD_HPP
+#define ENTT_CONTAINER_FWD_HPP
+
+#include "../stl/functional.hpp"
+#include "../stl/memory.hpp"
+#include "../stl/utility.hpp"
+#include "../stl/vector.hpp"
+
+namespace entt {
+
+template<
+    typename Key,
+    typename Type,
+    typename = stl::hash<Key>,
+    typename = stl::equal_to<>,
+    typename = stl::allocator<stl::pair<const Key, Type>>>
+class dense_map;
+
+template<
+    typename Type,
+    typename = stl::hash<Type>,
+    typename = stl::equal_to<>,
+    typename = stl::allocator<Type>>
+class dense_set;
+
+template<typename...>
+class basic_table;
+
+/**
+ * @brief Alias declaration for the most common use case.
+ * @tparam Type Element types.
+ */
+template<typename... Type>
+using table = basic_table<stl::vector<Type>...>;
+
+} // namespace entt
+
+#endif