From a3de58f3c153e5f35a34ebb635b8c65add6071b6 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 18 Jun 2023 00:40:21 +0300
Subject: [PATCH] Support custom lookup functions for retrieving setups in
 Spawner

---
 source/game/spawner.cpp |  2 +-
 source/game/spawner.h   | 34 ++++++++++++++++++++++------------
 2 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/source/game/spawner.cpp b/source/game/spawner.cpp
index f696d4d..9c0c3e6 100644
--- a/source/game/spawner.cpp
+++ b/source/game/spawner.cpp
@@ -45,7 +45,7 @@ void Spawner::spawn(const SpawnableType &type, const string &setup_name, const T
 	if(i==spawn_infos.end())
 		i = spawn_infos.emplace(spawn_infos.end(), make_unique<SpawnInfo>(this, type.type.get_name(), setup_name));
 
-	Owned<Entity> entity = (this->*type.create_func)(setup_name, tf);
+	Owned<Entity> entity = type.create_func(setup_name, tf);
 	if(Handle<Zygote> zygote = entity->get_component<Zygote>())
 		zygote->set_spawn_info(**i);
 	handler.spawned(move(entity));
diff --git a/source/game/spawner.h b/source/game/spawner.h
index 95ac903..0473e71 100644
--- a/source/game/spawner.h
+++ b/source/game/spawner.h
@@ -2,6 +2,7 @@
 #define MSP_GAME_SPAWNER_H_
 
 #include <algorithm>
+#include <functional>
 #include "messages.h"
 #include "owned.h"
 
@@ -28,11 +29,17 @@ public:
 
 class MSPGAME_API Spawner
 {
+public:
+	template<typename T>
+	using LookupFunc = std::function<const T &(const std::string &)>;
+
 private:
+	using CreateFunc = std::function<Owned<Entity>(const std::string &, const TransformValues &)>;
+
 	struct SpawnableType
 	{
 		const Reflection::ClassBase &type;
-		Owned<Entity> (Spawner::*create_func)(const std::string &, const TransformValues &) const;
+		CreateFunc create_func;
 	};
 
 	DataFile::Collection &resources;
@@ -50,6 +57,10 @@ public:
 		requires std::is_base_of_v<Entity, T>
 	void add_spawnable_type();
 
+	template<typename T>
+		requires std::is_base_of_v<Entity, T>
+	void add_spawnable_type(LookupFunc<typename T::Setup>);
+
 private:
 	void add_to_replicator(const std::string &);
 
@@ -64,20 +75,26 @@ public:
 
 private:
 	void spawn(const SpawnableType &, const std::string &, const TransformValues &);
-
-	template<typename T>
-	Owned<Entity> create(const std::string &, const TransformValues &) const;
 };
 
 
 template<typename T>
 	requires std::is_base_of_v<Entity, T>
 void Spawner::add_spawnable_type()
+{
+	add_spawnable_type<T>([this](const std::string &n) -> const typename T::Setup & { return resources.get<typename T::Setup>(n); });
+}
+
+template<typename T>
+	requires std::is_base_of_v<Entity, T>
+void Spawner::add_spawnable_type(LookupFunc<typename T::Setup> lookup_func)
 {
 	const Reflection::ClassBase &type = reflector.get_or_create_class<T>();
 	/* There's assumed to be only a few types per spawner, so sorting is not
 	necessary */
-	spawnable_types.emplace_back(type, &Spawner::create<T>);
+	spawnable_types.emplace_back(type, [this, lookup_func=std::move(lookup_func)](const std::string &sn, const TransformValues &tf){
+		return Owned<T>(parent, lookup_func(sn), tf);
+	});
 	add_to_replicator(type.get_name());
 }
 
@@ -93,13 +110,6 @@ void Spawner::spawn(const std::string &sname, const TransformValues &tf)
 	spawn(*i, sname, tf);
 }
 
-template<typename T>
-Owned<Entity> Spawner::create(const std::string &setup_name, const TransformValues &tf) const
-{
-	const typename T::Setup &setup = resources.get<typename T::Setup>(setup_name);
-	return Owned<T>(parent, setup, tf);
-}
-
 } // namespace Msp::Game
 
 #endif
-- 
2.45.2