Add some manual cleanup (experiemental)

src/app/core/controller.cc

@@ -157,7 +157,8 @@ void Controller::DoRender() const {
   SDL_RenderPresent(renderer_.get());
 }
 
-void Controller::OnExit() const {
+void Controller::OnExit() {
+  master_editor_.Shutdown();
   Mix_CloseAudio();
   ImGui_ImplSDLRenderer2_Shutdown();
   ImGui_ImplSDL2_Shutdown();

src/app/core/controller.h

@@ -27,7 +27,7 @@ class Controller {
   void OnInput();
   void OnLoad();
   void DoRender() const;
-  void OnExit() const;
+  void OnExit();
 
  private:
   struct sdl_deleter {

src/app/editor/master_editor.h

@@ -34,6 +34,9 @@ class MasterEditor : public SharedROM {
  public:
   void SetupScreen(std::shared_ptr<SDL_Renderer> renderer);
   void UpdateScreen();
+  void Shutdown() {
+    overworld_editor_.Shutdown();
+  }
 
  private:
   void DrawFileDialog();

src/app/gfx/bitmap.h

@@ -46,6 +46,32 @@ class Bitmap {
     this->pixel_data_[position] = value;
   }
 
+  void Cleanup() {
+    // Reset texture_
+    if (texture_) {
+      texture_.reset();
+    }
+
+    // Reset surface_ and its pixel data
+    if (surface_) {
+      surface_->pixels = nullptr;
+      surface_.reset();
+    }
+
+    // Reset data_
+    data_.clear();
+
+    // Reset other members if necessary
+    active_ = false;
+    pixel_data_ = nullptr;
+    width_ = 0;
+    height_ = 0;
+    depth_ = 0;
+    data_size_ = 0;
+    palette_.Clear();  // assuming there's a Clear() method or similar on
+                       // SNESPalette
+  }
+
   int width() const { return width_; }
   int height() const { return height_; }
   auto size() const { return data_size_; }