Entity remove working

src/run_modes/editor/editor.cpp

@@ -494,5 +494,11 @@ namespace editor
             if (mpMapEditor) mpMapEditor->ReloadTileSets();
         }
     }
+
+    
+    void Editor::OnEntityDelete(Entity* pEnt)
+    {
+        ((PropertiesView*)mPanelManager.GetPanel(mPanels.PropertiesView))->SetSelection((Entity*)nullptr);
+    }
 }
 }

src/run_modes/editor/editor.h

@@ -61,6 +61,7 @@ namespace lunarium { namespace editor
         void OnAssetSelected(EditorAsset* pAsset);
         void OnNewAsset(EditorAsset* pAsset);
         void OnAssetUpdate(EditorAsset* pAsset);
+        void OnEntityDelete(Entity* pEnt);
 
     private:
         Editor(const Editor&) = delete;

src/run_modes/editor/panels/world_tree.cpp

@@ -87,8 +87,6 @@ namespace lunarium { namespace editor
         if (ImGui::TreeNode("World Root"))
         {
             // List all world entities
-            // This will fail if we end up implementing child entities
-            // In that case this needs to become recursive
             int idx = 0;
             for (auto iter = mpWorld->EntitiesBegin(); !mpWorld->EntitiesIsEnd(iter); iter++, idx++)
             {
@@ -117,6 +115,35 @@ namespace lunarium { namespace editor
         bool was_right_clicked = false;
         if (ImGui::TreeNode(pEnt->GetName().c_str()))
         {
+            if (ImGui::BeginDragDropSource())
+            {
+                // Need to pass a pointer to the payload data. This means we need to pass a
+                // pointer to the Entity pointer (Entity**) which &(*pEnt) becomes
+                ImGui::SetDragDropPayload("Entity", (void *)&(*pEnt), sizeof(Entity *));
+                ImGui::Text("%s", pEnt->GetName().c_str());
+                ImGui::EndDragDropSource();
+            }
+
+            
+            if (ImGui::BeginDragDropTarget())
+            {
+                if (const ImGuiPayload *payload = ImGui::AcceptDragDropPayload("Entity"))
+                {
+                    Entity* pDroppedEnt = *((Entity**) payload->Data);
+
+                    // Can't drop and entity on itself
+                    if (pDroppedEnt != pEnt)
+                    {
+                        // If the dropped ent is the parent of pEnt then we need to swap the relationship
+
+                        // If the dropped ent is already a child of pEnt then we do nothing
+
+                        // Else add dropped ent as a child of pEnt
+                    }
+                }
+                ImGui::EndDragDropTarget();
+            }
+
             was_clicked = ImGui::IsItemClicked(ImGuiMouseButton_Left);
             was_right_clicked = ImGui::IsItemClicked(ImGuiMouseButton_Right);
             
@@ -166,6 +193,56 @@ namespace lunarium { namespace editor
                     OpenPopup(PopUp::NEW_ENTITY).LogIfFailed(Editor::LogCat);
                 }
             }
+
+            if (mNewChild)
+            {
+                if (ImGui::Button("Delete Entity"))
+                {
+                    // mParentEnt is the entity that was right-clicked on
+                    // Lets give it a less confusing name for this context
+                    Entity* ToRemove = mParentEnt;
+
+                    // Give the editor a chance to clean up any refs to this entity
+                    mpEditor->OnEntityDelete(ToRemove);
+
+                    // If this entity has a parent we need to patch some relationships
+                    bool has_parent = false;
+                    LUUID parent_id = 0;
+                    if (ToRemove->HasComponent<ParentEntityComponent>())
+                    {
+                        // These will be used to patch the children to the grandparent - now the parent
+                        parent_id = ToRemove->GetComponent<ParentEntityComponent>().Parent;
+                        has_parent = true;
+
+                        // Tell the parent this child does not exist anymore
+                        mpWorld->GetEntity(parent_id)->RemoveChild(ToRemove->GetUUID());
+                    }
+
+                    if (ToRemove->HasChildren())
+                    {
+                        auto children = ToRemove->GetChildren();
+                        for (LUUID child : children)
+                        {
+                            // Clear the parent for each child
+                            mpWorld->GetEntity(child)->ClearParent();
+
+                            if (has_parent)
+                            {
+                                // Make the grandparent the new parent (if there is a grandparent)
+                                mpWorld->GetEntity(parent_id)->AddChild(child);
+                            }
+                        }
+                    }
+
+                    // Relationships are all patched so finally remove the entity
+                    mpWorld->RemoveEntity(ToRemove->GetUUID());
+                }
+
+                if (ImGui::Button("Delete Hierarchy"))
+                {
+
+                }
+            }
             ImGui::EndPopup();
         }
     }

src/world/world.cpp

@@ -151,6 +151,25 @@ namespace lunarium
     }
 
     
+    void World::RemoveEntity(LUUID id)
+    {
+        Entity* temp = mEntitiesByUUID[id];
+        mEntitiesByUUID.erase(id);
+        
+        for (auto iter = mEntities.begin(); iter != mEntities.end(); iter++)
+        {
+            if ((*iter)->GetUUID() == id)
+            {
+                mEntities.erase(iter);
+                break;
+            }
+        }
+
+        mECSRegistry.destroy(temp->GetEnttHandle());
+        delete temp;
+    }
+
+    
     Entity* World::GetEntity(LUUID id)
     {
         if (mEntitiesByUUID.find(id) == mEntitiesByUUID.end())

src/world/world.h

@@ -77,6 +77,7 @@ namespace lunarium
 
         entt::registry* GetEntityRegistry();
         LUUID CreateEntity();
+        void RemoveEntity(LUUID id);
         Entity* GetEntity(LUUID id);
         unsigned int GetNumEntities() const;
         std::vector<Entity*>::iterator EntitiesBegin();