contentpack removal feature + refactor

src/frontend/screens.h

@@ -15,7 +15,7 @@ class LevelFrontend;
 class LevelController;
 class TextureAnimator;
 
-/* Screen is a mainloop state */
+/// @brief Screen is a mainloop state
 class Screen {
 protected:
     Engine* engine;
@@ -25,6 +25,7 @@ public:
     virtual ~Screen();
     virtual void update(float delta) = 0;
     virtual void draw(float delta) = 0;
+    virtual void onEngineShutdown() {};
 };
 
 class MenuScreen : public Screen {
@@ -52,6 +53,10 @@ public:
 
     void update(float delta) override;
     void draw(float delta) override;
+
+    void onEngineShutdown() override;
+
+    LevelController* getLevelController() const;
 };
 
 #endif // FRONTEND_SCREENS_H_