update to entt v3.9.0 and add clone functionality

Author: Green-Sky

README.md

@@ -51,8 +51,8 @@ editor.registerComponent<Velocity>("Velocity");
 ```
 
 # Dependencies
-The editor uses EnTTv3.6.0 interface and ImGui. (tested with ImGui 1.68, 1.72b, 1.75, 1.78, 1.82)
+The editor uses EnTTv3.9.0 and ImGui. (tested with ImGui 1.68, 1.72b, 1.75, 1.78, 1.82, 1.85)
 To use it with EnTTv3.0.0, use the dedicated branch.
 For specific EnTT version check the tags, if a new EnTT version does not require a update, I won't make a new Release.
-Releases available for EnTT 3.1.0, 3.1.1, 3.2.0, 3.2.1, 3.2.2, 3.3.x, 3.4.0, 3.6.0 .
+Releases available for EnTT 3.1.0, 3.1.1, 3.2.0, 3.2.1, 3.2.2, 3.3.x, 3.4.0, 3.6.0-3.8.1, 3.9.0.
 

imgui_entt_entity_editor.hpp

@@ -129,11 +129,19 @@ class EntityEditor {
 		if (registry.valid(e)) {
 			ImGui::SameLine();
 
-			// clone would go here
-			//if (ImGui::Button("Clone")) {
-				//auto old_e = e;
-				//e = registry.create();
-			//}
+			if (ImGui::Button("Clone")) {
+				auto old_e = e;
+				e = registry.create();
+
+				// create a copy of an entity component by component
+				for (auto &&curr: registry.storage()) {
+					if (auto &storage = curr.second; storage.contains(old_e)) {
+						// TODO: do something with the return value. returns false on failure.
+						storage.emplace(e, storage.get(old_e));
+					}
+				}
+			}
+			ImGui::SameLine();
 
 			ImGui::Dummy({10, 0}); // space destroy a bit, to not accidentally click it
 			ImGui::SameLine();
@@ -229,8 +237,10 @@ class EntityEditor {
 
 		if (comp_list.empty()) {
 			ImGui::Text("Orphans:");
-			registry.orphans([&registry](auto e){
-				MM_IEEE_ENTITY_WIDGET(e, registry, false);
+			registry.each([&registry](auto e){
+				if (registry.orphan(e)) {
+					MM_IEEE_ENTITY_WIDGET(e, registry, false);
+				}
 			});
 		} else {
 			auto view = registry.runtime_view(comp_list.begin(), comp_list.end());