JeanPhilippeKernel · jnyfah · Aug 25, 2026
diff --git a/Tetragrama/Components/InspectorViewUIComponent.cpp b/Tetragrama/Components/InspectorViewUIComponent.cpp
@@ -186,6 +186,37 @@ namespace
         ImGui::PopID();
     }
 
+    void AddComponentPopup(Scene& scene, EntityID id)
+    {
+        if (!ImGui::BeginPopup("##add_component_popup"))
+            return;
+
+        const ArchetypeMask mask = scene.GetMask(id);
+        bool                any  = false;
+
+        ComponentReflectionRegistry::Get().ForEach([&](const ComponentMeta& meta) {
+            if (MaskHas(mask, meta.TypeID))
+            {
+                return; // already on the entity
+            }
+            if (!meta.Add)
+            {
+                return;
+            }
+            if (ImGui::Selectable(meta.TypeName))
+            {
+                scene.AddComponentRaw(id, meta.TypeID);
+            }
+        });
+
+        if (!any)
+        {
+            ImGui::TextDisabled("No components left to add");
+        }
+
+        ImGui::EndPopup();
+    }
+
     void DrawEntityComponents(Scene& scene, EntityID id)
     {
         static constexpr ImGuiTableFlags kTableFlags = ImGuiTableFlags_NoPadInnerX | ImGuiTableFlags_NoPadOuterX;
@@ -326,7 +357,9 @@ namespace Tetragrama::Components
             float tx = btn_scr.x + 8.f;
             cdl->AddText({tx, ty}, IM_COL32(90, 210, 120, 255), "+");
             cdl->AddText({tx + ImGui::CalcTextSize("+").x + 5.f, ty}, ImGui::GetColorU32(ImGuiCol_Text), "Add");
-            (void) add_clicked;
+            if (add_clicked)
+                ImGui::OpenPopup("##add_component_popup");
+            AddComponentPopup(*ctx->Scene, actor->GetEntityID());
 
             ImGui::EndChild();
             ImGui::PopStyleColor();

diff --git a/ZEngine/ZEngine/ECS/Components/CameraComponent.cpp b/ZEngine/ZEngine/ECS/Components/CameraComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/CameraComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -23,6 +24,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "Camera",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<CC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/LightComponent.cpp b/ZEngine/ZEngine/ECS/Components/LightComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/LightComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -33,6 +34,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "Lighting",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<LC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/MaterialComponent.cpp b/ZEngine/ZEngine/ECS/Components/MaterialComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/MaterialComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -19,6 +20,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "Rendering",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<MatC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/MeshComponent.cpp b/ZEngine/ZEngine/ECS/Components/MeshComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/MeshComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -20,6 +21,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "Rendering",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<MC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/NameComponent.cpp b/ZEngine/ZEngine/ECS/Components/NameComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/NameComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -19,6 +20,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "General",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<NC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/RigidBodyComponent.cpp b/ZEngine/ZEngine/ECS/Components/RigidBodyComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/RigidBodyComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -29,6 +30,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "Physics",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<RBC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/TransformComponent.cpp b/ZEngine/ZEngine/ECS/Components/TransformComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/TransformComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -23,6 +24,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "Transform",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<TC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Components/UUIDComponent.cpp b/ZEngine/ZEngine/ECS/Components/UUIDComponent.cpp
@@ -1,5 +1,6 @@
 #include <ZEngine/ECS/Components/UUIDComponent.h>
 #include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
+#include <ZEngine/ECS/Scene.h>
 
 namespace ZEngine::ECS::Components
 {
@@ -19,6 +20,7 @@ namespace ZEngine::ECS::Components
             .Fields     = kFields,
             .FieldCount = static_cast<uint32_t>(sizeof(kFields) / sizeof(kFields[0])),
             .Category   = "General",
+            .Add        = [](Scene& scene, EntityID id) { scene.AddComponent<UC>(id, {}); },
         });
     }
 } // namespace ZEngine::ECS::Components
diff --git a/ZEngine/ZEngine/ECS/Reflection/ComponentMeta.h b/ZEngine/ZEngine/ECS/Reflection/ComponentMeta.h
@@ -1,10 +1,12 @@
 #pragma once
 #include <ZEngine/ECS/ComponentTypeID.h>
+#include <ZEngine/ECS/EntityID.h>
 #include <ZEngine/ECS/Reflection/FieldType.h>
 #include <cstdint>
 
 namespace ZEngine::ECS
 {
+    class Scene;
 
     struct EnumValue
     {
@@ -40,6 +42,9 @@ namespace ZEngine::ECS
         uint32_t               FieldCount = 0;
         const char*            Category   = "General"; // compare with strcmp, not ==
         const char*            Tooltip    = nullptr;
+
+        using AddFn                       = void (*)(Scene&, EntityID);
+        AddFn Add                         = nullptr;
     };
 
 } // namespace ZEngine::ECS
diff --git a/ZEngine/ZEngine/ECS/Scene.cpp b/ZEngine/ZEngine/ECS/Scene.cpp
@@ -1,4 +1,5 @@
 #include <ZEngine/ECS/Components/TransformComponent.h>
+#include <ZEngine/ECS/Reflection/ComponentReflectionRegistry.h>
 #include <ZEngine/ECS/Scene.h>
 #include <ZEngine/ZEngineDef.h>
 
@@ -70,6 +71,20 @@ namespace ZEngine::ECS
         });
     }
 
+    void Scene::AddComponentRaw(EntityID id, ComponentTypeID type_id)
+    {
+        if (!IsAlive(id) || MaskHas(m_registry.GetMask(id), type_id))
+        {
+            return;
+        }
+
+        const ComponentMeta* meta = ComponentReflectionRegistry::Get().Lookup(type_id);
+        if (meta && meta->Add)
+        {
+            meta->Add(*this, id);
+        }
+    }
+
     void* Scene::GetComponentRaw(EntityID id, ComponentTypeID type_id)
     {
         IComponentStorage** found = m_storages.find(type_id);

diff --git a/ZEngine/ZEngine/ECS/Scene.h b/ZEngine/ZEngine/ECS/Scene.h
@@ -102,6 +102,11 @@ namespace ZEngine::ECS
         // Call once per render frame before submitting to the renderer.
         void        FillRenderableTransforms(float alpha, Core::Containers::Array<RenderableTransform>& out);
 
+        // Adds a default-constructed component via the type's registered reflection
+        // factory. No-op if the type is unregistered, has no factory, or the entity
+        // already has it.
+        void        AddComponentRaw(EntityID id, ComponentTypeID type_id);
+
         void*       GetComponentRaw(EntityID id, ComponentTypeID type_id);
         const void* GetComponentRaw(EntityID id, ComponentTypeID type_id) const;