refactor: 移除未使用的类型定义并简化监听器链表操作

- 删除 EventTrait 和 TupleExtractor 中未使用的 FuncType 类型别名
- 删除 AssetsModule 中未使用的缓存、默认资源、互斥锁及相关数据结构
- 提取监听器链表追加操作为独立函数以消除重复代码

include/assets/assets_module.h

@@ -4,20 +4,16 @@
 #include <assets/core/asset_system.h>
 #include <assets/asset_loader.h>
 #include <assets/handle.h>
-#include <atomic>
 #include <event/events.h>
 #include <functional>
 #include <memory>
 #include <module/module.h>
 #include <module/module_registry.h>
-#include <mutex>
 #include <renderer/material.h>
 #include <renderer/mesh.h>
 #include <renderer/shader.h>
 #include <renderer/texture.h>
-#include <shared_mutex>
 #include <string>
-#include <unordered_map>
 #include <vector>
 
 namespace extra2d {
@@ -261,19 +257,6 @@ private:
   std::unique_ptr<AssetLoader<Texture>> textureLoader_;
   std::unique_ptr<AssetLoader<Shader>> shaderLoader_;
 
-  // 路径缓存（避免重复加载）
-  std::unordered_map<std::string, Handle<Texture>> texturePathCache_;
-  std::unordered_map<std::string, Handle<Shader>> shaderPathCache_;
-
-  // 默认资源
-  Handle<Texture> defaultTexture_;
-  Handle<Shader> defaultShader_;
-  Handle<Material> defaultMaterial_;
-  Handle<Mesh> defaultQuad_;
-
-  // 线程安全
-  mutable std::shared_mutex mutex_;
-
   // 事件监听器
   std::unique_ptr<events::OnShow::Listener> onShowListener_;
 
@@ -286,12 +269,9 @@ private:
 public:
   struct LoadTask {
     enum class Type { Texture, Shader };
-    enum class Priority { Low = 0, Normal = 1, High = 2 };
 
     Type type;
-    Priority priority;
     std::string path;
-    std::string secondaryPath; // 用于着色器的片段着色器路径
     std::function<void(Handle<Texture>)> textureCallback;
     std::function<void(Handle<Shader>)> shaderCallback;
   };
@@ -321,15 +301,6 @@ public:
   // 资源依赖跟踪
   //===========================================================================
 public:
-  /**
-   * @brief 资源依赖关系
-   */
-  struct DependencyInfo {
-    Handle<Texture> texture;
-    Handle<Shader> shader;
-    std::vector<Handle<Material>> dependentMaterials;
-  };
-
   /**
    * @brief 注册材质对纹理的依赖
    */

include/event/event_bus.h

@@ -79,13 +79,11 @@ struct EventTrait {
  */
 template<typename T>
 struct TupleExtractor {
-    using FuncType = void();
     using StdFuncType = std::function<void()>;
 };
 
 template<typename... Args>
 struct TupleExtractor<std::tuple<Args...>> {
-    using FuncType = void(Args...);
     using StdFuncType = std::function<void(Args...)>;
 };
 
@@ -120,9 +118,6 @@ public:
         }
     }
 
-    const char* busName() const { return EHandler::BUS_NAME; }
-    const char* eventName() const { return EHandler::NAME; }
-
 private:
     bool enabled_ = true;
     StdFuncType callback_;

src/event/event_bus.cpp

@@ -2,6 +2,21 @@
 
 namespace extra2d::event {
 
+static void appendListenerEntry(ListenerEntry *&head, ListenerEntry *entry) {
+  entry->next = nullptr;
+  entry->prev = nullptr;
+  if (!head) {
+    head = entry;
+    return;
+  }
+  ListenerEntry *tail = head;
+  while (tail->next) {
+    tail = tail->next;
+  }
+  tail->next = entry;
+  entry->prev = tail;
+}
+
 ListenerContainer::~ListenerContainer() {
   ListenerEntry *curr = listenerList_;
   while (curr) {
@@ -27,34 +42,9 @@ void ListenerContainer::addListener(ListenerBase *listener) {
     return;
 
   if (broadcasting_ > 0) {
-    // 广播期间，添加到待添加列表（保持顺序，使用尾插）
-    listener->entry_->next = nullptr;
-    if (!listenersToAdd_) {
-      listenersToAdd_ = listener->entry_;
+    appendListenerEntry(listenersToAdd_, listener->entry_);
   } else {
-      // 找到尾部
-      ListenerEntry* tail = listenersToAdd_;
-      while (tail->next) {
-        tail = tail->next;
-      }
-      tail->next = listener->entry_;
-    }
-  } else {
-    // 非广播期间，添加到主列表尾部（保持顺序）
-    listener->entry_->next = nullptr;
-    listener->entry_->prev = nullptr;
-    
-    if (!listenerList_) {
-      listenerList_ = listener->entry_;
-    } else {
-      // 找到尾部
-      ListenerEntry* tail = listenerList_;
-      while (tail->next) {
-        tail = tail->next;
-      }
-      tail->next = listener->entry_;
-      listener->entry_->prev = tail;
-    }
+    appendListenerEntry(listenerList_, listener->entry_);
   }
 }
 
@@ -85,13 +75,7 @@ void ListenerContainer::processPendingListeners() {
   while (listenersToAdd_) {
     ListenerEntry *entry = listenersToAdd_;
     listenersToAdd_ = entry->next;
-
-    entry->next = listenerList_;
-    entry->prev = nullptr;
-    if (listenerList_) {
-      listenerList_->prev = entry;
-    }
-    listenerList_ = entry;
+    appendListenerEntry(listenerList_, entry);
   }
 
   for (auto *entry : listenersToRemove_) {