add service locator

.gitignore

@@ -3,3 +3,4 @@ bin/
 debug/
 external/
 compile_commands.json
+src/*~

src/asset.cpp

@@ -1,3 +1,4 @@
+#include <algorithm>
 #include <asset/asset.hpp>
 
 #include <asset/raylib_asset.hpp>
@@ -9,6 +10,7 @@
 #include <iostream>
 #include <filesystem>
 #include <variant>
+#include <ranges>
 
 
 namespace fs = std::filesystem;
@@ -104,6 +106,7 @@ void RaylibAssetLoader::load_asset(std::string path){
 }
 
 void RaylibAssetLoader::unload_asset(std::string path){
+    if (!assets.contains(path)) return;
     Asset asset = assets[path];
 
     std::visit([](auto&& arg) {
@@ -136,7 +139,9 @@ void RaylibAssetLoader::unload_asset(std::string path){
 
 
 void RaylibAssetLoader::unload_all_assets(){
-    for (auto [path,_] : assets){
+    std::vector<std::string> assets_to_unload;
+    std::ranges::copy(std::views::keys(assets),std::back_inserter(assets_to_unload));
+    for (const auto &path : assets_to_unload){
         unload_asset(path);
     }
 }

src/include/asset/raylib_asset.hpp

@@ -25,7 +25,7 @@ class RaylibAssetLoader : public AssetLoader{
 };
 
 
-extern RaylibAssetLoader asset_loader;
+// extern RaylibAssetLoader asset_loader;
 
 
 

src/include/locator.hpp

@@ -1,3 +1,24 @@
 #pragma once
+#include <scene.hpp>
+#include <asset/raylib_asset.hpp>
 
-class ServiceLocator{};
+// A simple Service Locator
+class ServiceLocator {
+private:
+    static inline SceneManager* s_scene_manager = nullptr;
+    static inline RaylibAssetLoader* s_asset_loader = nullptr;
+
+    // static inline Configuration* s_config = nullptr;
+
+    // static inline AssetManager* s_assets = nullptr;
+
+public:
+    static void provide(SceneManager* service) { s_scene_manager = service; }
+    static void provide(RaylibAssetLoader* service) { s_asset_loader = service; }
+
+    static SceneManager& get_scene_manager() { return *s_scene_manager; }
+    static RaylibAssetLoader& get_asset_loader() { return *s_asset_loader; }
+
+    // static SceneManager& get_config() { return *s_config; }
+    // static AssetManager& GetAssets() { return *s_assets; }
+};

src/include/scene.hpp

@@ -10,26 +10,6 @@ enum class SceneType{
 };
 
 
-// Simple global data structure to hold the switch request
-struct EngineState {
-    bool pendingSwitch = false;
-    SceneType nextScene;
-
-    bool shouldQuit = false;
-
-    void request_switch(SceneType type) {
-        nextScene = type;
-        pendingSwitch = true;
-    }
-
-    void quit(){
-        shouldQuit = true;
-    }
-};
-
-// Expose the global state to any file that includes scene.hpp
-extern EngineState g_Engine;
-
 
 class Scene{
 
@@ -73,9 +53,11 @@ class SceneManager{
     private:
         Scene* current_scene = nullptr;
         SceneType next_scene_type;
-        bool should_switch = false;
+        bool pending_switch = false;
+        bool should_quit = false;
 
     public:
+
         SceneManager();
         ~SceneManager();
         
@@ -83,4 +65,7 @@ class SceneManager{
         void render();
         void ui();
         void process_scene_switch();
+        bool should_game_close();
+        void request_switch(SceneType type);
+        void quit();
 };

src/locator.cpp

@@ -1,3 +0,0 @@
-#include <locator.hpp>
-
-// Will contain definition of service locator class 

src/main.cpp

@@ -1,3 +1,4 @@
+#include "locator.hpp"
 #include <asset/raylib_asset.hpp>
 #include <scene.hpp>
 #include <components.hpp>
@@ -16,13 +17,6 @@
 #include <emscripten.h>
 #endif
 
-// Globals
-EngineState g_Engine; 
-RaylibAssetLoader asset_loader;
-
-entt::registry * registry;
-SceneManager* scene_manager;
-
 void UpdateDrawFrame(void) {
     // Update
 
@@ -31,20 +25,20 @@ void UpdateDrawFrame(void) {
     if (dt > 0.1f) dt = 0.1f; 
 
     // Draw
-    scene_manager->update(dt);
+    ServiceLocator::get_scene_manager().update(dt);
 
     BeginDrawing();
     ClearBackground(RAYWHITE);
 
-    scene_manager->render();
+    ServiceLocator::get_scene_manager().render();
 
     rlImGuiBegin();
-    scene_manager->ui();
+    ServiceLocator::get_scene_manager().ui();
     rlImGuiEnd();
 
     EndDrawing();
 
-    scene_manager->process_scene_switch(); // !!! After scene_manager is done with the current loop
+    ServiceLocator::get_scene_manager().process_scene_switch(); // !!! After scene_manager is done with the current loop
 }
 
 int main(){
@@ -53,9 +47,11 @@ int main(){
     int screen_width = 1280;
     int screen_height = 800;
 
-    // initialized scene manager
-    scene_manager = new SceneManager();
-    registry = new entt::registry();
+    RaylibAssetLoader asset_loader;  
+    SceneManager scene_manager;  
+
+    ServiceLocator::provide(&asset_loader); 
+    ServiceLocator::provide(&scene_manager); // Depends on asset loader!
 
     rlImGuiSetup(true);
 
@@ -86,15 +82,13 @@ int main(){
 #ifdef __EMSCRIPTEN__
     emscripten_set_main_loop(UpdateDrawFrame, 0, 1);
 #else
-    while (!WindowShouldClose() && !g_Engine.shouldQuit){
+    while (!ServiceLocator::get_scene_manager().should_game_close()){
         UpdateDrawFrame();
     }
 #endif
 
     CloseWindow();
     rlImGuiShutdown();
-    delete scene_manager;
-    delete registry;
     return 0;
 }
 

src/scenes/game_play_scene.cpp

@@ -1,3 +1,4 @@
+#include "locator.hpp"
 #include <player.hpp>
 #include <movement.hpp>
 #include <scene.hpp>
@@ -13,10 +14,10 @@
 GamePlayScene::GamePlayScene() {
     registry = entt::registry();
 
-    asset_loader.load_asset("assets/snake_head.png");
-    asset_loader.load_asset("assets/fruit.png");
-    create_player(registry,asset_loader.get_texture("assets/snake_head.png"));
-    create_fruit(registry,asset_loader.get_texture("assets/fruit.png"));
+    ServiceLocator::get_asset_loader().load_asset("assets/snake_head.png");
+    ServiceLocator::get_asset_loader().load_asset("assets/fruit.png");
+    create_player(registry,ServiceLocator::get_asset_loader().get_texture("assets/snake_head.png"));
+    create_fruit(registry,ServiceLocator::get_asset_loader().get_texture("assets/fruit.png"));
 
 }
 
@@ -47,13 +48,17 @@ void GamePlayScene::ui() {
     ImGui::Begin("Exit", nullptr, flags);
 
     if (ImGui::Button("X",{40.f,40.f})){
-        g_Engine.request_switch(SceneType::MENU);
+        ServiceLocator::get_scene_manager().request_switch(SceneType::MENU);
     }
 
     ImGui::End();
 }
 
 GamePlayScene::~GamePlayScene(){
-    asset_loader.unload_asset("assets/snake_head.png");
-    asset_loader.unload_asset("assets/fruit.png");
+
+    ServiceLocator::get_scene_manager();
+    ServiceLocator::get_asset_loader();
+
+    ServiceLocator::get_asset_loader().unload_asset("assets/snake_head.png");
+    ServiceLocator::get_asset_loader().unload_asset("assets/fruit.png");
 }

src/scenes/menu_scene.cpp

@@ -1,3 +1,4 @@
+#include "locator.hpp"
 #include <player.hpp>
 #include <movement.hpp>
 #include <scene.hpp>
@@ -38,13 +39,13 @@ void MenuScene::ui() {
 
     // ImGui::SetCursorPos(centeredPos);
     if (ImGui::Button("Play",button_size)){
-        g_Engine.request_switch(SceneType::GAMEPLAY);
+        ServiceLocator::get_scene_manager().request_switch(SceneType::GAMEPLAY);
     }
 
     ImGui::Dummy(ImVec2(0, 10)); // Gap
 
     if (ImGui::Button("Quit",button_size)){
-        g_Engine.quit();   
+        ServiceLocator::get_scene_manager().quit();   
     }
 
     ImGui::End();

src/scenes/scene.cpp

@@ -1,3 +1,4 @@
+#include "raylib.h"
 #include <scene.hpp>
 
 SceneManager::SceneManager(){
@@ -9,11 +10,14 @@ SceneManager::~SceneManager(){
 }
 
 void SceneManager::process_scene_switch(){
-    if (!g_Engine.pendingSwitch) return;
     
-    delete current_scene;
+    if (!pending_switch) return;
+    
+    if (current_scene){
+        delete current_scene;
+    }
 
-    switch(g_Engine.nextScene){
+    switch(next_scene_type){
         case SceneType::MENU:
             current_scene = new MenuScene();
             break;
@@ -21,19 +25,32 @@ void SceneManager::process_scene_switch(){
             current_scene = new GamePlayScene();
             break;
     }
-    g_Engine.pendingSwitch = false;
+    pending_switch = false;
 }
 
 void SceneManager::update(float dt){
-    if (current_scene){
-        current_scene->update(dt);
-    }
+    if (!current_scene) return;
+    current_scene->update(dt);
 }
 
 void SceneManager::render(){
-        current_scene->render();
+    if (!current_scene) return;
+    current_scene->render();
 }
 
 void SceneManager::ui(){
-        current_scene->ui();
+    if (!current_scene) return;
+    current_scene->ui();
+}
+
+bool SceneManager::should_game_close(){
+    return should_quit || WindowShouldClose();
+}
+
+void SceneManager::request_switch(SceneType type){
+        next_scene_type = type;
+        pending_switch = true;
+}
+void SceneManager::quit(){
+    should_quit = true;
 }