cocos2d-x 3.1.1源码阅读过程的注释

cocos2d-x 3.1.1源码阅读过程的注释

印象笔记链接：http://app.yinxiang.com/l/AAU8F1mKiN9BIqFopReAU3ZbTcgGOULycQo/

Ref

每个类的基类是Ref 也就是2.0的CCObject 调用继承下来的下面的那个函数

class CC_DLL Ref

{

public :

/**

引用计数+1

*/

void retain();

{

CCASSERT (_referenceCount > 0, "reference count should greater than 0" );

++_referenceCount;

}

/**

引用计数-1

*/

void release();

{

CCASSERT (_referenceCount > 0, "reference count should greater than 0" );

--_referenceCount;

if (_referenceCount == 0)

{

#if defined ( COCOS2D_DEBUG ) && ( COCOS2D_DEBUG > 0)

auto poolManager = PoolManager ::getInstance();

if (!poolManager->getCurrentPool()->isClearing() && poolManager->isObjectInPools( this ))

{

// 错误实例1：

// auto obj = Node::create();

// obj->autorelease();

//create函数里面封装了 autorelease

// 错误实例2：

// auto obj = Node::create();

// obj->release(); // Wrong: obj is an autorelease Ref,it will be released when clearing current pool.

CCASSERT ( false , "The reference shouldn't be 0 because it is still in autorelease pool." );

}

#endif

#if CC_USE_MEM_LEAK_DETECTION

untrackRef( this );

#endif

delete this ;

}

/**

* 自动释放 也就是当前的AutoReleasePool被调用了析构函数之后 引擎全局有一个 AutoReleasePool

*/

Ref * autorelease();

{

PoolManager ::getInstance()->getCurrentPool()->addObject( this );

return this ;

}

/**

* 返回引用数量

*/

unsigned int getReferenceCount() const ;

protected :

/**

* 在构造了之后引用计数是1！！！！！

*/

Ref()

: _referenceCount(1) // when the Ref is created,the reference count of it is 1

{

#if CC_ENABLE_SCRIPT_BINDING

static unsigned int uObjectCount = 0;

_luaID = 0;

_ID = ++uObjectCount;

#endif

#if CC_USE_MEM_LEAK_DETECTION

trackRef( this );

#endif

}

public :

virtual ~Ref();

protected :

/// count of references

unsigned int _referenceCount;

friend class AutoreleasePool ;

#if CC_ENABLE_SCRIPT_BINDING

public :

/// object id,ScriptSupport need public _ID

unsigned int _ID;

/// Lua reference id

int _luaID;

#endif

#if CC_USE_MEM_LEAK_DETECTION

public :

static void printLeaks();

#endif

};

PoolManager类的解析：

class CC_DLL PoolManager

{

public :

//这个是表示这个接口以后要丢弃

CC_DEPRECATED_ATTRIBUTE static PoolManager * sharedPoolManager() { return getInstance(); }

/**

这里也是十分重要的 整个程序只有一个单例的PoolManager PoolManager初始化的时候就添加了一个 AutoreleasePool

*/

static PoolManager * getInstance();

{

if (s_singleInstance == nullptr )

{

s_singleInstance = new PoolManager ();

// Add the first auto release pool

s_singleInstance->_curReleasePool = new AutoreleasePool ( "cocos2d autorelease pool" );

s_singleInstance->_releasePoolStack.push_back(s_singleInstance->_curReleasePool);

}

return s_singleInstance;

}

CC_DEPRECATED_ATTRIBUTE static void purgePoolManager() { destroyInstance(); }

static void destroyInstance();

/**

* 获得现在的释放池,引擎自己创建了一个autoreleasePool

* 你可以创建自己的释放池 会放进自动释放池的盏变量里面

*/

AutoreleasePool *getCurrentPool() const ;

{

return _curReleasePool;

}

bool isObjectInPools( Ref * obj) const ;

friend class AutoreleasePool ;

private :

PoolManager();

~PoolManager();

void push( AutoreleasePool *pool);

{

_releasePoolStack.push_back( pool );

_curReleasePool = pool ;

}

void pop();

{

// 如果是弹出第一个

CC_ASSERT (_releasePoolStack.size() >= 1);

_releasePoolStack.pop_back();

// 应该更新 _curReleasePool

if (_releasePoolStack.size() > 1)

{

_curReleasePool = _releasePoolStack.back();

}

}

static PoolManager * s_singleInstance;//单例模式

std:: deque < AutoreleasePool *> _releasePoolStack;//管理用户创建的自动释放池用的盏

AutoreleasePool *_curReleasePool;//现在的自动释放池

};

AutoreleasePool

class CC_DLL AutoreleasePool

{

public :

/**

* 提示：自动释放池对象要创建在栈里面 不能再堆里面

* 创建的时候就自动push进PoolManager里面

*/

AutoreleasePool();

{

_managedObjectArray.reserve(150);//vector扩大容量

PoolManager ::getInstance()->push( this );

}

/**

* 用引用来创建 是为了调试

*/

AutoreleasePool( const std:: string &name);

{

_managedObjectArray.reserve(150);

PoolManager ::getInstance()->push( this );

}

// 枚举每一个加进对象池的obj去调用release 并且清空

~AutoreleasePool();

{

CCLOGINFO ( "deallocing AutoreleasePool: %p" , this );

clear();//

PoolManager ::getInstance()->pop();

}

/**

* 添加对象到对象池中

* 对象池销毁的时候会调用

*/

void addObject( Ref *object);

{

_managedObjectArray.push_back( object );

}

/**

清理对象池 析构函数调用

*/

void clear();

{

#if defined ( COCOS2D_DEBUG ) && ( COCOS2D_DEBUG > 0)

_isClearing = true ;

#endif

for ( const auto &obj : _managedObjectArray)

{

//枚举每一个加进对象池的obj去调用release

obj->release();

}

//把vector清空

_managedObjectArray.clear();

#if defined ( COCOS2D_DEBUG ) && ( COCOS2D_DEBUG > 0)

_isClearing = false ;

#endif

}

#if defined ( COCOS2D_DEBUG ) && ( COCOS2D_DEBUG > 0)

/**

* Whether the pool is doing `clear` operation.

*/

bool isClearing() const { return _isClearing; };

#endif

/**

* 检查是否包含

* 枚举一遍这个vector

*/

bool contains( Ref * object) const ;

{

for ( const auto & obj : _managedObjectArray)

{

if (obj == object )

return true ;

}

return false ;

}

/**

* 用来调试

*

*/

void dump();

{

CCLOG ( "autorelease pool: %s,number of managed object %d\n" ,_name.c_str(), static_cast < int >(_managedObjectArray.size()));

CCLOG ( "%20s%20s%20s" , "Object pointer" , "Object id" , "reference count" );

for ( const auto &obj : _managedObjectArray)

{

CC_UNUSED_PARAM (obj);

CCLOG ( "%20p%20u\n" ,obj,obj->getReferenceCount());

}

}

private :

/**

* The underlying array of object managed by the pool.

*

* Although Array retains the object once when an object is added,proper

* Ref::release() is called outside the array to make sure that the pool

* does not affect the managed object's reference count. So an object can

* be destructed properly by calling Ref::release() even if the object

* is in the pool.

*/

std:: vector < Ref *> _managedObjectArray;

std:: string _name;

#if defined ( COCOS2D_DEBUG ) && ( COCOS2D_DEBUG > 0)

/**

* The flag for checking whether the pool is doing `clear` operation.

*/

bool _isClearing;

#endif

};

下面这张图是网上找的类图继承图：