cocos2d-x的引用计数

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

Ref::~Ref()
{
#if CC_REF_LEAK_DETECTION
    if (_referenceCount != 0) // 没有异常使用的情况下 _referenceCount 为 0
        untrackRef(this);
#endif
}

void Ref::retain()
{
    CCASSERT(_referenceCount > 0, "reference count should greater than 0");
    ++_referenceCount;
}

void Ref::release()
{
    CCASSERT(_referenceCount > 0, "reference count should greater than 0");
    --_referenceCount;
        delete this;
    }
}