Fixing view caches

lib/wal/sources/Scene/Scene.cpp

@@ -6,7 +6,9 @@
 
 namespace WAL
 {
-	std::vector<Entity> &Scene::getEntities()
+	int Scene::_nextID = 0;
+
+	std::list<Entity> &Scene::getEntities()
 	{
 		return this->_entities;
 	}

lib/wal/sources/Scene/Scene.hpp

@@ -6,6 +6,7 @@
 #pragma once
 
 #include <vector>
+#include <list>
 #include <functional>
 #include <View/View.hpp>
 #include "Entity/Entity.hpp"
@@ -16,8 +17,12 @@ namespace WAL
 	class Scene
 	{
 	private:
+		static int _nextID;
+		//! @brief An ID representing this scene.
+		int _id = _nextID++;
+
 		//! @brief The list of registered entities
-		std::vector<Entity> _entities = {};
+		std::list<Entity> _entities = {};
 		//! @brief The list of cached views to update.
 		std::vector<std::shared_ptr<BaseView>> _views = {};
 
@@ -31,7 +36,7 @@ namespace WAL
 		void _componentRemoved(const Entity &entity, const std::type_index &type);
 	public:
 		//! @brief Get the list of entities.
-		std::vector<Entity> &getEntities();
+		std::list<Entity> &getEntities();
 
 		//! @brief Add a new entity to the scene.
 		//! @param name The name of the created entity.
@@ -41,8 +46,13 @@ namespace WAL
 		template<typename ...Components>
 		View<Components...> &view()
 		{
-			static auto view = std::make_shared<View<Components...>>(this->_entities);
+			static std::unordered_map<int, std::weak_ptr<View<Components...>>> cache;
+			auto existing = cache.find(this->_id);
+			if (existing != cache.end() && !existing->second.expired())
+				return *existing->second.lock();
+			auto view = std::make_shared<View<Components...>>(this->_entities);
 			this->_views.emplace_back(view);
+			cache.emplace(this->_id, view);
 			return *view;
 		}
 

lib/wal/sources/View/View.hpp

@@ -5,7 +5,7 @@
 
 #pragma once
 
-#include <vector>
+#include <list>
 #include <tuple>
 #include <typeindex>
 #include <functional>
@@ -47,7 +47,7 @@ namespace WAL
 	public:
 		//! @brief Construct a view from a list of entities.
 		//!        Those entities are never copied but references to them are kept internally.
-		explicit View(std::vector<Entity> &scene)
+		explicit View(std::list<Entity> &scene)
 		{
 			this->types = {typeid(Components)...};
 			std::copy_if(scene.begin(), scene.end(), std::back_inserter(this->entities), [](Entity &entity) {

tests/CollisionTest.cpp

@@ -32,7 +32,7 @@ TEST_CASE("Collision test", "[Component][System]")
 			pos.position.z = 1;
 			} catch (std::exception &e) {};
 		}, [](Entity &, const Entity &){}, 5.0);
-	Entity &entity = wal.scene->getEntities()[0];
+	Entity &entity = wal.scene->getEntities().front();
 	REQUIRE(entity.getComponent<PositionComponent>().position == Vector3f());
 
 	entity.getComponent<CollisionComponent>().bound.x = 5;
@@ -48,7 +48,7 @@ TEST_CASE("Collision test", "[Component][System]")
 	wal.scene->addEntity("block")
 		.addComponent<PositionComponent>(2,2,2)
 		.addComponent<CollisionComponent>(1);
-	Entity &player = wal.scene->getEntities()[0];
+	Entity &player = wal.scene->getEntities().front();
 	collision.onUpdate(entity, std::chrono::nanoseconds(1));
 	REQUIRE(player.hasComponent(typeid(PositionComponent)));
 	collision.onFixedUpdate(player);
@@ -79,7 +79,7 @@ TEST_CASE("Collsion test with movable", "[Component][System]")
 			mov.resetVelocity();
 			} catch (std::exception &e) {};
 		}, 1);
-	Entity &entity = wal.scene->getEntities()[0];
+	Entity &entity = wal.scene->getEntities().front();
 	REQUIRE(entity.getComponent<PositionComponent>().position == Vector3f());
 
 	entity.getComponent<CollisionComponent>().bound.x = 5;

tests/MoveTests.cpp

@@ -25,7 +25,7 @@ TEST_CASE("Move test", "[Component][System]")
 		.addComponent<ControllableComponent>()
 		.addComponent<MovableComponent>()
 		.addComponent<PositionComponent>();
-	Entity &entity = scene.getEntities()[0];
+	Entity &entity = *scene.getEntities().begin();
 
 	REQUIRE(entity.getComponent<PositionComponent>().position == Vector3f());
 

tests/ViewTest.cpp

@@ -50,6 +50,22 @@ TEST_CASE("View cache", "[View]")
 	REQUIRE(&view == &scene.view<PositionComponent>());
 }
 
+TEST_CASE("View cache switch", "[View]")
+{
+	Scene scene;
+	scene.addEntity("player")
+		.addComponent<PositionComponent>()
+		.addComponent<ControllableComponent>();
+	auto &view = scene.view<PositionComponent>();
+	Scene scene2;
+	scene2.addEntity("box")
+		.addComponent<PositionComponent>();
+
+	REQUIRE(&view == &scene.view<PositionComponent>());
+	REQUIRE(view.entities.begin()->get().getName() == "player");
+	REQUIRE(scene2.view<PositionComponent>().entities.begin()->get().getName() == "box");
+}
+
 //TEST_CASE("View iteration", "[View]")
 //{
 //	Scene scene;