Refactored overlay_widget.cpp to improve lifetime management

src/editor/editor.hpp

@@ -140,7 +140,7 @@ class Editor final : public Screen,
 
   bool is_level_loaded() const { return m_levelloaded; }
 
-  void edit_path(Path* path, GameObject* new_marked_object) {
+  void edit_path(PathGameObject* path, GameObject* new_marked_object) {
     m_overlay_widget->edit_path(path, new_marked_object);
   }
 

src/editor/layers_widget.cpp

@@ -175,11 +175,11 @@ EditorLayersWidget::on_mouse_button_down(const SDL_MouseButtonEvent& button)
             }
             m_selected_tilemap = static_cast<TileMap*>(m_layer_icons[m_hovered_layer]->get_layer());
             m_selected_tilemap->m_editor_active = true;
-            m_editor.edit_path(m_selected_tilemap->get_path(), m_selected_tilemap);
+            m_editor.edit_path(m_selected_tilemap->get_path_gameobject(), m_selected_tilemap);
           } else {
             auto cam = dynamic_cast<Camera*>(m_layer_icons[m_hovered_layer]->get_layer());
             if (cam) {
-              m_editor.edit_path(cam->get_path(), cam);
+              m_editor.edit_path(cam->get_path_gameobject(), cam);
             }
           }
           return true;

src/editor/overlay_widget.cpp

@@ -471,7 +471,7 @@ EditorOverlayWidget::hover_object()
 }
 
 void
-EditorOverlayWidget::edit_path(Path* path, GameObject* new_marked_object)
+EditorOverlayWidget::edit_path(PathGameObject* path, GameObject* new_marked_object)
 {
   if (!path) return;
   delete_markers();
@@ -481,7 +481,7 @@ EditorOverlayWidget::edit_path(Path* path, GameObject* new_marked_object)
     return;
   }
   m_edited_path = path;
-  m_edited_path->edit_path();
+  m_edited_path->get_path().edit_path();
   if (new_marked_object) {
     m_selected_object = new_marked_object;
   }
@@ -509,10 +509,10 @@ EditorOverlayWidget::select_object()
     return;
   }
 
-  auto path_obj = dynamic_cast<PathObject*>(m_dragged_object);
-  if (path_obj && path_obj->get_path())
+  auto path_obj = dynamic_cast<PathObject*>(m_dragged_object.get());
+  if (path_obj && path_obj->get_path_gameobject())
   {
-    edit_path(path_obj->get_path(), m_dragged_object);
+    edit_path(path_obj->get_path_gameobject(), m_dragged_object.get());
   }
 }
 
@@ -529,7 +529,7 @@ EditorOverlayWidget::grab_object()
       m_dragged_object = m_hovered_object;
       m_obj_mouse_desync = m_sector_pos - m_hovered_object->get_pos();
 
-      auto* pm = dynamic_cast<MarkerObject*>(m_hovered_object);
+      auto* pm = dynamic_cast<MarkerObject*>(m_hovered_object.get());
       if (!pm) {
         select_object();
       }
@@ -560,7 +560,7 @@ EditorOverlayWidget::clone_object()
       return;
     }
 
-    auto* pm = dynamic_cast<MarkerObject*>(m_hovered_object);
+    auto* pm = dynamic_cast<MarkerObject*>(m_hovered_object.get());
     if (!pm)
     {
       m_obj_mouse_desync = m_sector_pos - m_hovered_object->get_pos();
@@ -612,7 +612,7 @@ EditorOverlayWidget::move_object()
       auto& snap_grid_size = snap_grid_sizes[g_config->editor_selected_snap_grid_size];
       new_pos = glm::floor(new_pos / static_cast<float>(snap_grid_size)) * static_cast<float>(snap_grid_size);
 
-      auto pm = dynamic_cast<MarkerObject*>(m_dragged_object);
+      auto pm = dynamic_cast<MarkerObject*>(m_dragged_object.get());
       if (pm) {
         new_pos -= pm->get_offset();
       }
@@ -685,10 +685,10 @@ EditorOverlayWidget::add_path_node()
   new_node.bezier_before = new_node.position;
   new_node.bezier_after = new_node.position;
   new_node.time = 1;
-  m_edited_path->m_nodes.insert(m_last_node_marker->m_node + 1, new_node);
-  auto& bezier_before = Sector::get().add<BezierMarker>(&(*(m_edited_path->m_nodes.end() - 1)), &((m_edited_path->m_nodes.end() - 1)->bezier_before));
-  auto& bezier_after = Sector::get().add<BezierMarker>(&(*(m_edited_path->m_nodes.end() - 1)), &((m_edited_path->m_nodes.end() - 1)->bezier_after));
-  auto& new_marker = Sector::get().add<NodeMarker>(m_edited_path, m_edited_path->m_nodes.end() - 1, m_edited_path->m_nodes.size() - 1, bezier_before.get_uid(), bezier_after.get_uid());
+  m_edited_path->get_path().m_nodes.insert(m_last_node_marker->m_node + 1, new_node);
+  auto& bezier_before = Sector::get().add<BezierMarker>(&(*(m_edited_path->get_path().m_nodes.end() - 1)), &((m_edited_path->get_path().m_nodes.end() - 1)->bezier_before));
+  auto& bezier_after = Sector::get().add<BezierMarker>(&(*(m_edited_path->get_path().m_nodes.end() - 1)), &((m_edited_path->get_path().m_nodes.end() - 1)->bezier_after));
+  auto& new_marker = Sector::get().add<NodeMarker>(&(m_edited_path.get()->get_path()), m_edited_path->get_path().m_nodes.end() - 1, m_edited_path->get_path().m_nodes.size() - 1, bezier_before.get_uid(), bezier_after.get_uid());
   bezier_before.set_parent(new_marker.get_uid());
   bezier_after.set_parent(new_marker.get_uid());
   //last_node_marker = dynamic_cast<NodeMarker*>(marker.get());
@@ -1206,14 +1206,14 @@ EditorOverlayWidget::draw_path(DrawingContext& context)
   if (!m_selected_object->is_valid()) return;
   if (!m_edited_path->is_valid()) return;
 
-  for (auto i = m_edited_path->m_nodes.begin(); i != m_edited_path->m_nodes.end(); ++i) {
+  for (auto i = m_edited_path->get_path().m_nodes.begin(); i != m_edited_path->get_path().m_nodes.end(); ++i) {
     auto j = i+1;
     Path::Node* node1 = &(*i);
     Path::Node* node2;
-    if (j == m_edited_path->m_nodes.end()) {
-      if (m_edited_path->m_mode == WalkMode::CIRCULAR) {
+    if (j == m_edited_path->get_path().m_nodes.end()) {
+      if (m_edited_path->get_path().m_mode == WalkMode::CIRCULAR) {
         //loop to the first node
-        node2 = &(*m_edited_path->m_nodes.begin());
+        node2 = &(*m_edited_path->get_path().m_nodes.begin());
       } else {
         // Just draw the bezier lines
         auto cam_translation = m_editor.get_sector()->get_camera().get_translation();

src/editor/overlay_widget.hpp

@@ -24,6 +24,7 @@
 #include "editor/widget.hpp"
 #include "math/vector.hpp"
 #include "object/tilemap.hpp"
+#include "util/typed_uid.hpp"
 
 class Color;
 class DrawingContext;
@@ -62,7 +63,7 @@ class EditorOverlayWidget final : public Widget
   void update_node_iterators();
   void on_level_change();
 
-  void edit_path(Path* path, GameObject* new_marked_object = nullptr);
+  void edit_path(PathGameObject* path, GameObject* new_marked_object = nullptr);
   void reset_action_press();
 
 private:
@@ -124,12 +125,12 @@ class EditorOverlayWidget final : public Widget
   bool m_dragging;
   bool m_dragging_right;
   Vector m_drag_start;
-  MovingObject* m_dragged_object;
+  TypedUID<MovingObject> m_dragged_object;
 
-  MovingObject* m_hovered_object;
-  GameObject* m_selected_object;
-  Path* m_edited_path;
-  NodeMarker* m_last_node_marker;
+  TypedUID<MovingObject> m_hovered_object;
+  TypedUID<GameObject> m_selected_object;
+  TypedUID<PathGameObject> m_edited_path;
+  TypedUID<NodeMarker> m_last_node_marker;
 
   std::unique_ptr<Tip> m_object_tip;
   Vector m_obj_mouse_desync;

src/object/path_gameobject.cpp

@@ -208,6 +208,17 @@ PathGameObject::remove_me()
       handle.remove_me(); // Removing a node handle also removes its bezier handles
   }
 
+  const auto& path_objects = Sector::get().get_objects_by_type<PathObject>();
+
+  for (const auto& path_obj : path_objects)
+  {
+    if (path_obj.get_path_gameobject() == this)
+    {
+      log_warning << "Attempt to delete path " << get_name() << " while bound to object" << std::endl;
+      return;
+    }
+  }
+
   GameObject::remove_me();
 }
 

src/util/typed_uid.hpp

@@ -0,0 +1,107 @@
+//  SuperTux
+//  Copyright (C) 2021 A. Semphris <semphris@protonmail.com>
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef HEADER_SUPERTUX_UTIL_TYPED_UID_HPP
+#define HEADER_SUPERTUX_UTIL_TYPED_UID_HPP
+
+#include "util/uid.hpp"
+
+#include "supertux/sector.hpp"
+
+/**
+ * Typed UIDs allows storing GameObjects as UID while offering to option to use
+ * the object either as if it was a pointer or as if it was an UID. This helps
+ * staying resilient against the objects' variable lifetime.
+ */
+template<class T>
+class TypedUID : public UID
+{
+public:
+  TypedUID() : UID() {}
+  TypedUID(const T* object) : UID() { if (object) *this = object->get_uid(); }
+  TypedUID(const TypedUID& other) = default;
+  TypedUID& operator=(const TypedUID& other) = default;
+
+  inline T* get() const
+  {
+    if (m_value == 0 || !Sector::current())
+      return nullptr;
+
+    auto* object = Sector::get().get_object_by_uid<T>(*this);
+
+    if (!object)
+    {
+      //*this = UID(); // Would break const correctness
+      throw std::runtime_error("Attempt to dereference invalid TypedUID");
+    }
+
+    return object;
+  }
+
+  inline TypedUID& operator=(const T* object)
+  {
+    *this = object ? object->get_uid() : UID();
+    return *this;
+  }
+
+  inline TypedUID& operator=(const UID& other)
+  {
+    UID::operator=(other);
+    return *this;
+  }
+
+  inline T* operator->() const
+  {
+    return get();
+  }
+
+  inline T& operator*() const
+  {
+    T* t = get();
+    if (!t)
+      throw std::runtime_error("Attempt to dereference invalid TypedUID");
+
+    return *t;
+  }
+
+  inline bool operator==(const T* object) const
+  {
+    return (!object && m_value == 0) || object->get_uid() == *this;
+  }
+
+  inline bool operator!=(const T* object) const
+  {
+    return object ? object->get_uid() != *this : m_value == 0;
+  }
+
+  inline operator bool() const {
+    return m_value != 0 && Sector::current() && Sector::get().get_object_by_uid<T>(*this);
+  }
+};
+
+template<class T>
+inline bool operator==(const T* object, const TypedUID<T>& typed_uid) {
+  return typed_uid == object;
+}
+
+template<class T>
+inline bool operator!=(const T* object, const TypedUID<T>& typed_uid) {
+  return typed_uid != object;
+}
+
+#endif
+
+/* EOF */

src/util/uid.hpp

@@ -73,7 +73,7 @@ class UID
 
   inline Magic get_magic() const { return static_cast<Magic>((m_value & 0xffff0000u) >> 16); }
 
-private:
+protected:
   uint32_t m_value;
 };