diff options
| author | Alec Thomas <alec@swapoff.org> | 2013-04-01 11:51:29 -0400 |
|---|---|---|
| committer | Alec Thomas <alec@swapoff.org> | 2013-04-02 17:50:58 -0400 |
| commit | 947d29aa374b9b5f5c581120ce5a4e7a32d0c981 (patch) | |
| tree | 9a22cf41b4db463ff17e964fe36e78e3219d46d9 /README.md | |
| parent | e569dc47c9ff3c3118cb96427d3ec9a6aced98aa (diff) | |
Allow shared_ptr implementation to be selected.
Fixes #6.
Diffstat (limited to 'README.md')
| -rw-r--r-- | README.md | 18 |
1 files changed, 10 insertions, 8 deletions
@@ -1,5 +1,7 @@ # EntityX - A fast, type-safe C++ Entity-Component system +[](https://travis-ci.org/alecthomas/entityx) + Entity-Component (EC) systems are a form of decomposition that completely decouples entity logic and data from the entity "objects" themselves. The [Evolve your Hierarchy](http://cowboyprogramming.com/2007/01/05/evolve-your-heirachy/) article provides a solid overview of EC systems and why you should use them. EntityX is an EC system that uses C++11 features to provide type-safe component management, event delivery, etc. It was built during the creation of a 2D space shooter. @@ -76,7 +78,7 @@ entity.assign<Position>(1.0f, 2.0f); You can also assign existing instances of components: ```c++ -boost::shared_ptr<Position> position = boost::make_shared<Position>(1.0f, 2.0f); +entityx::shared_ptr<Position> position = entityx::make_shared<Position>(1.0f, 2.0f); entity.assign(position); ``` @@ -86,8 +88,8 @@ To query all entities with a set of components assigned, use ``EntityManager::en ```c++ for (auto entity : entities.entities_with_components<Position, Direction>()) { - boost::shared_ptr<Position> position = entity.component<Position>(); - boost::shared_ptr<Direction> direction = entity.component<Direction>(); + entityx::shared_ptr<Position> position = entity.component<Position>(); + entityx::shared_ptr<Direction> direction = entity.component<Direction>(); // Do things with entity, position and direction. } @@ -96,7 +98,7 @@ for (auto entity : entities.entities_with_components<Position, Direction>()) { To retrieve a component associated with an entity use ``Entity::component<C>()``: ```c++ -boost::shared_ptr<Position> position = entity.component<Position>(); +entityx::shared_ptr<Position> position = entity.component<Position>(); if (position) { // Do stuff with position } @@ -117,8 +119,8 @@ A basic movement system might be implemented with something like the following: struct MovementSystem : public System<MovementSystem> { void update(EntityManager &es, EventManager &events, double dt) override { for (auto entity : es.entities_with_components<Position, Direction>()) { - boost::shared_ptr<Position> position = entity.component<Position>(); - boost::shared_ptr<Direction> direction = entity.component<Direction>(); + entityx::shared_ptr<Position> position = entity.component<Position>(); + entityx::shared_ptr<Direction> direction = entity.component<Direction>(); position->x += direction->x * dt; position->y += direction->y * dt; @@ -154,7 +156,7 @@ Next we implement our collision system, which emits ``Collision`` objects via an class CollisionSystem : public System<CollisionSystem> { public: void update(EntityManager &es, EventManager &events, double dt) override { - boost::shared_ptr<Position> left_position, right_position; + entityx::shared_ptr<Position> left_position, right_position; for (auto left_entity : es.entities_with_components<Position>()) { for (auto right_entity : es.entities_with_components<Position>()) { if (collide(left_position, right_position)) { @@ -192,7 +194,7 @@ Several events are emitted by EntityX itself: - `Entity entity` - Entity about to be destroyed. - `ComponentAddedEvent<T>` - emitted when a new component is added to an entity. - `Entity entity` - Entity that component was added to. - - `boost::shared_ptr<T> component` - The component added. + - `entityx::shared_ptr<T> component` - The component added. #### Implementation notes |