Split Entity and ComponentHandle into their own headers

3 files changed, 213 insertions, 180 deletions

diff --git a/entityx/ComponentHandle.h b/entityx/ComponentHandle.h
new file mode 100644
index 0000000..9406705
--- /dev/null
+++ b/entityx/ComponentHandle.h
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2012 Alec Thomas <alec@swapoff.org>
+ * All rights reserved.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution.
+ *
+ * Author: Alec Thomas <alec@swapoff.org>
+ */
+
+#pragma once
+
+namespace entityx {
+
+class EntityManager;
+
+/**
+ * A ComponentHandle<C> is a wrapper around an instance of a component.
+ *
+ * It provides safe access to components. The handle will be invalidated under
+ * the following conditions:
+ *
+ * - If a component is removed from its host entity.
+ * - If its host entity is destroyed.
+ */
+template <typename C, typename EM>
+class ComponentHandle {
+public:
+  typedef C ComponentType;
+
+  ComponentHandle() : manager_(nullptr) {}
+
+  bool valid() const;
+  operator bool() const;
+
+  C *operator -> ();
+  const C *operator -> () const;
+
+  C *get();
+  const C *get() const;
+
+  /**
+   * Remove the component from its entity and destroy it.
+   */
+  void remove();
+
+  bool operator == (const ComponentHandle<C> &other) const {
+    return manager_ == other.manager_ && id_ == other.id_;
+  }
+
+  bool operator != (const ComponentHandle<C> &other) const {
+    return !(*this == other);
+  }
+
+private:
+  friend class EntityManager;
+
+  ComponentHandle(EM *manager, Entity::Id id) :
+      manager_(manager), id_(id) {}
+
+  EM *manager_;
+  Entity::Id id_;
+};
+
+}
diff --git a/entityx/Entity.h b/entityx/Entity.h
index 3d0b96f..8e1e93e 100644
--- a/entityx/Entity.h
+++ b/entityx/Entity.h
@@ -27,12 +27,14 @@
 #include <utility>
 #include <vector>
 #include <type_traits>
- #include <functional>
+#include <functional>
 
 #include "entityx/help/Pool.h"
+#include "entityx/EntityClass.h"
 #include "entityx/config.h"
 #include "entityx/Event.h"
 #include "entityx/help/NonCopyable.h"
+#include "entityx/ComponentHandle.h"
 
 namespace entityx {
 
@@ -41,185 +43,6 @@ typedef std::uint64_t uint64_t;
 
 class EntityManager;
 
-
-template <typename C, typename EM = EntityManager>
-class ComponentHandle;
-
-
-
-/** A convenience handle around an Entity::Id.
- *
- * If an entity is destroyed, any copies will be invalidated. Use valid() to
- * check for validity before using.
- *
- * Create entities with `EntityManager`:
- *
- *     Entity entity = entity_manager->create();
- */
-class Entity {
-public:
-  struct Id {
-    Id() : id_(0) {}
-    explicit Id(uint64_t id) : id_(id) {}
-    Id(uint32_t index, uint32_t version) : id_(uint64_t(index) | uint64_t(version) << 32UL) {}
-
-    uint64_t id() const { return id_; }
-
-    bool operator == (const Id &other) const { return id_ == other.id_; }
-    bool operator != (const Id &other) const { return id_ != other.id_; }
-    bool operator < (const Id &other) const { return id_ < other.id_; }
-
-    uint32_t index() const { return id_ & 0xffffffffUL; }
-    uint32_t version() const { return id_ >> 32; }
-
-  private:
-    friend class EntityManager;
-
-    uint64_t id_;
-  };
-
-
-  /**
-   * Id of an invalid Entity.
-   */
-  static const Id INVALID;
-
-  Entity() = default;
-  Entity(EntityManager *manager, Entity::Id id) : manager_(manager), id_(id) {}
-  Entity(const Entity &other) = default;
-  Entity &operator = (const Entity &other) = default;
-
-  /**
-   * Check if Entity handle is invalid.
-   */
-  operator bool() const {
-    return valid();
-  }
-
-  bool operator == (const Entity &other) const {
-    return other.manager_ == manager_ && other.id_ == id_;
-  }
-
-  bool operator != (const Entity &other) const {
-    return !(other == *this);
-  }
-
-  bool operator < (const Entity &other) const {
-    return other.id_ < id_;
-  }
-
-  /**
-   * Is this Entity handle valid?
-   *
-   * In older versions of EntityX, there were no guarantees around entity
-   * validity if a previously allocated entity slot was reassigned. That is no
-   * longer the case: if a slot is reassigned, old Entity::Id's will be
-   * invalid.
-   */
-  bool valid() const;
-
-  /**
-   * Invalidate Entity handle, disassociating it from an EntityManager and invalidating its ID.
-   *
-   * Note that this does *not* affect the underlying entity and its
-   * components. Use destroy() to destroy the associated Entity and components.
-   */
-  void invalidate();
-
-  Id id() const { return id_; }
-
-  template <typename C, typename ... Args>
-  ComponentHandle<C> assign(Args && ... args);
-
-  template <typename C>
-  ComponentHandle<C> assign_from_copy(const C &component);
-
-  template <typename C, typename ... Args>
-  ComponentHandle<C> replace(Args && ... args);
-
-  template <typename C>
-  void remove();
-
-  template <typename C, typename = typename std::enable_if<!std::is_const<C>::value>::type>
-  ComponentHandle<C> component();
-
-  template <typename C, typename = typename std::enable_if<std::is_const<C>::value>::type>
-  const ComponentHandle<C, const EntityManager> component() const;
-
-  template <typename ... Components>
-  std::tuple<ComponentHandle<Components>...> components();
-
-  template <typename ... Components>
-  std::tuple<ComponentHandle<const Components, const EntityManager>...> components() const;
-
-  template <typename C>
-  bool has_component() const;
-
-  template <typename A, typename ... Args>
-  void unpack(ComponentHandle<A> &a, ComponentHandle<Args> & ... args);
-
-  /**
-   * Destroy and invalidate this Entity.
-   */
-  void destroy();
-
-  std::bitset<entityx::MAX_COMPONENTS> component_mask() const;
-
- private:
-  EntityManager *manager_ = nullptr;
-  Entity::Id id_ = INVALID;
-};
-
-
-/**
- * A ComponentHandle<C> is a wrapper around an instance of a component.
- *
- * It provides safe access to components. The handle will be invalidated under
- * the following conditions:
- *
- * - If a component is removed from its host entity.
- * - If its host entity is destroyed.
- */
-template <typename C, typename EM>
-class ComponentHandle {
-public:
-  typedef C ComponentType;
-
-  ComponentHandle() : manager_(nullptr) {}
-
-  bool valid() const;
-  operator bool() const;
-
-  C *operator -> ();
-  const C *operator -> () const;
-
-  C *get();
-  const C *get() const;
-
-  /**
-   * Remove the component from its entity and destroy it.
-   */
-  void remove();
-
-  bool operator == (const ComponentHandle<C> &other) const {
-    return manager_ == other.manager_ && id_ == other.id_;
-  }
-
-  bool operator != (const ComponentHandle<C> &other) const {
-    return !(*this == other);
-  }
-
-private:
-  friend class EntityManager;
-
-  ComponentHandle(EM *manager, Entity::Id id) :
-      manager_(manager), id_(id) {}
-
-  EM *manager_;
-  Entity::Id id_;
-};
-
-
 /**
  * Base component class, only used for insertion into collections.
  *
diff --git a/entityx/EntityClass.h b/entityx/EntityClass.h
new file mode 100644
index 0000000..444e494
--- /dev/null
+++ b/entityx/EntityClass.h
@@ -0,0 +1,145 @@
+/*
+ * Copyright (C) 2012 Alec Thomas <alec@swapoff.org>
+ * All rights reserved.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution.
+ *
+ * Author: Alec Thomas <alec@swapoff.org>
+ */
+
+#pragma once
+
+#include "entityx/config.h"
+
+namespace entityx {
+
+class EntityManager;
+
+template <typename C, typename EM = EntityManager>
+class ComponentHandle;
+
+/** A convenience handle around an Entity::Id.
+ *
+ * If an entity is destroyed, any copies will be invalidated. Use valid() to
+ * check for validity before using.
+ *
+ * Create entities with `EntityManager`:
+ *
+ *     Entity entity = entity_manager->create();
+ */
+class Entity {
+public:
+  struct Id {
+    Id() : id_(0) {}
+    explicit Id(uint64_t id) : id_(id) {}
+    Id(uint32_t index, uint32_t version) : id_(uint64_t(index) | uint64_t(version) << 32UL) {}
+
+    uint64_t id() const { return id_; }
+
+    bool operator == (const Id &other) const { return id_ == other.id_; }
+    bool operator != (const Id &other) const { return id_ != other.id_; }
+    bool operator < (const Id &other) const { return id_ < other.id_; }
+
+    uint32_t index() const { return id_ & 0xffffffffUL; }
+    uint32_t version() const { return id_ >> 32; }
+
+  private:
+    friend class EntityManager;
+
+    uint64_t id_;
+  };
+
+
+  /**
+   * Id of an invalid Entity.
+   */
+  static const Id INVALID;
+
+  Entity() = default;
+  Entity(EntityManager *manager, Entity::Id id) : manager_(manager), id_(id) {}
+  Entity(const Entity &other) = default;
+  Entity &operator = (const Entity &other) = default;
+
+  /**
+   * Check if Entity handle is invalid.
+   */
+  operator bool() const {
+    return valid();
+  }
+
+  bool operator == (const Entity &other) const {
+    return other.manager_ == manager_ && other.id_ == id_;
+  }
+
+  bool operator != (const Entity &other) const {
+    return !(other == *this);
+  }
+
+  bool operator < (const Entity &other) const {
+    return other.id_ < id_;
+  }
+
+  /**
+   * Is this Entity handle valid?
+   *
+   * In older versions of EntityX, there were no guarantees around entity
+   * validity if a previously allocated entity slot was reassigned. That is no
+   * longer the case: if a slot is reassigned, old Entity::Id's will be
+   * invalid.
+   */
+  bool valid() const;
+
+  /**
+   * Invalidate Entity handle, disassociating it from an EntityManager and invalidating its ID.
+   *
+   * Note that this does *not* affect the underlying entity and its
+   * components. Use destroy() to destroy the associated Entity and components.
+   */
+  void invalidate();
+
+  Id id() const { return id_; }
+
+  template <typename C, typename ... Args>
+  ComponentHandle<C> assign(Args && ... args);
+
+  template <typename C>
+  ComponentHandle<C> assign_from_copy(const C &component);
+
+  template <typename C, typename ... Args>
+  ComponentHandle<C> replace(Args && ... args);
+
+  template <typename C>
+  void remove();
+
+  template <typename C, typename = typename std::enable_if<!std::is_const<C>::value>::type>
+  ComponentHandle<C> component();
+
+  template <typename C, typename = typename std::enable_if<std::is_const<C>::value>::type>
+  const ComponentHandle<C, const EntityManager> component() const;
+
+  template <typename ... Components>
+  std::tuple<ComponentHandle<Components>...> components();
+
+  template <typename ... Components>
+  std::tuple<ComponentHandle<const Components, const EntityManager>...> components() const;
+
+  template <typename C>
+  bool has_component() const;
+
+  template <typename A, typename ... Args>
+  void unpack(ComponentHandle<A> &a, ComponentHandle<Args> & ... args);
+
+  /**
+   * Destroy and invalidate this Entity.
+   */
+  void destroy();
+
+  std::bitset<entityx::MAX_COMPONENTS> component_mask() const;
+
+ private:
+  EntityManager *manager_ = nullptr;
+  Entity::Id id_ = INVALID;
+};
+
+}