fixed main screen

src/app/AssetLoader.cpp

@@ -0,0 +1,122 @@
+#include "app/AssetLoader.h"
+#include <SDL3_image/SDL_image.h>
+#include <algorithm>
+
+AssetLoader::AssetLoader() = default;
+
+AssetLoader::~AssetLoader() {
+    shutdown();
+}
+
+void AssetLoader::init(SDL_Renderer* renderer) {
+    m_renderer = renderer;
+}
+
+void AssetLoader::shutdown() {
+    // Destroy textures
+    {
+        std::lock_guard<std::mutex> lk(m_texturesMutex);
+        for (auto &p : m_textures) {
+            if (p.second) SDL_DestroyTexture(p.second);
+        }
+        m_textures.clear();
+    }
+
+    // Clear queue and errors
+    {
+        std::lock_guard<std::mutex> lk(m_queueMutex);
+        m_queue.clear();
+    }
+    {
+        std::lock_guard<std::mutex> lk(m_errorsMutex);
+        m_errors.clear();
+    }
+
+    m_totalTasks = 0;
+    m_loadedTasks = 0;
+    m_renderer = nullptr;
+}
+
+void AssetLoader::setBasePath(const std::string& basePath) {
+    m_basePath = basePath;
+}
+
+void AssetLoader::queueTexture(const std::string& path) {
+    {
+        std::lock_guard<std::mutex> lk(m_queueMutex);
+        m_queue.push_back(path);
+    }
+    m_totalTasks.fetch_add(1, std::memory_order_relaxed);
+}
+
+bool AssetLoader::performStep() {
+    std::string path;
+    {
+        std::lock_guard<std::mutex> lk(m_queueMutex);
+        if (m_queue.empty()) return true;
+        path = m_queue.front();
+        m_queue.erase(m_queue.begin());
+    }
+
+    {
+        std::lock_guard<std::mutex> lk(m_currentLoadingMutex);
+        m_currentLoading = path;
+    }
+
+    std::string fullPath = m_basePath.empty() ? path : (m_basePath + "/" + path);
+
+    SDL_Surface* surf = IMG_Load(fullPath.c_str());
+    if (!surf) {
+        std::lock_guard<std::mutex> lk(m_errorsMutex);
+        m_errors.push_back(std::string("IMG_Load failed: ") + fullPath + " -> " + SDL_GetError());
+    } else {
+        SDL_Texture* tex = SDL_CreateTextureFromSurface(m_renderer, surf);
+        SDL_DestroySurface(surf);
+        if (!tex) {
+            std::lock_guard<std::mutex> lk(m_errorsMutex);
+            m_errors.push_back(std::string("CreateTexture failed: ") + fullPath);
+        } else {
+            std::lock_guard<std::mutex> lk(m_texturesMutex);
+            m_textures[path] = tex;
+        }
+    }
+
+    m_loadedTasks.fetch_add(1, std::memory_order_relaxed);
+
+    {
+        std::lock_guard<std::mutex> lk(m_currentLoadingMutex);
+        m_currentLoading.clear();
+    }
+
+    // Return true when no more queued tasks
+    {
+        std::lock_guard<std::mutex> lk(m_queueMutex);
+        return m_queue.empty();
+    }
+}
+
+float AssetLoader::getProgress() const {
+    int total = m_totalTasks.load(std::memory_order_relaxed);
+    if (total <= 0) return 1.0f;
+    int loaded = m_loadedTasks.load(std::memory_order_relaxed);
+    return static_cast<float>(loaded) / static_cast<float>(total);
+}
+
+std::vector<std::string> AssetLoader::getAndClearErrors() {
+    std::lock_guard<std::mutex> lk(m_errorsMutex);
+    std::vector<std::string> out = m_errors;
+    m_errors.clear();
+    return out;
+}
+
+SDL_Texture* AssetLoader::getTexture(const std::string& path) const {
+    std::lock_guard<std::mutex> lk(m_texturesMutex);
+    auto it = m_textures.find(path);
+    if (it == m_textures.end()) return nullptr;
+    return it->second;
+}
+
+std::string AssetLoader::getCurrentLoading() const {
+    std::lock_guard<std::mutex> lk(m_currentLoadingMutex);
+    return m_currentLoading;
+}

src/app/AssetLoader.h

@@ -0,0 +1,64 @@
+#pragma once
+
+#include <SDL3/SDL.h>
+#include <string>
+#include <vector>
+#include <mutex>
+#include <atomic>
+#include <unordered_map>
+
+// Lightweight AssetLoader scaffold.
+// Responsibilities:
+// - Queue textures to load (main thread) and perform incremental loads via performStep().
+// - Store loaded SDL_Texture* instances and provide accessors.
+// - Collect loading errors thread-safely.
+// NOTE: All SDL texture creation MUST happen on the thread that owns the SDL_Renderer.
+class AssetLoader {
+public:
+    AssetLoader();
+    ~AssetLoader();
+
+    void init(SDL_Renderer* renderer);
+    void shutdown();
+
+    void setBasePath(const std::string& basePath);
+
+    // Queue a texture path (relative to base path) for loading.
+    void queueTexture(const std::string& path);
+
+    // Perform a single loading step (load one queued asset).
+    // Returns true when all queued tasks are complete, false otherwise.
+    bool performStep();
+
+    // Progress in [0,1]. If no tasks, returns 1.0f.
+    float getProgress() const;
+
+    // Retrieve and clear accumulated error messages.
+    std::vector<std::string> getAndClearErrors();
+
+    // Get a loaded texture (or nullptr if not loaded).
+    SDL_Texture* getTexture(const std::string& path) const;
+
+    // Return currently-loading path (empty when idle).
+    std::string getCurrentLoading() const;
+
+private:
+    SDL_Renderer* m_renderer = nullptr;
+    std::string m_basePath;
+
+    // queued paths (simple FIFO)
+    std::vector<std::string> m_queue;
+    mutable std::mutex m_queueMutex;
+
+    std::unordered_map<std::string, SDL_Texture*> m_textures;
+    mutable std::mutex m_texturesMutex;
+
+    std::vector<std::string> m_errors;
+    mutable std::mutex m_errorsMutex;
+
+    std::atomic<int> m_totalTasks{0};
+    std::atomic<int> m_loadedTasks{0};
+
+    std::string m_currentLoading;
+    mutable std::mutex m_currentLoadingMutex;
+};