Cocos2d-x结构学习十二CCMoveBy、CCActionInterval、CCFiniteTimeAction、CCCallFunc、CC_SAFE_RETAIN、CCActionInst

1、CCMoveBy：移动动作，继承自CCActionInterval

class CC_DLL CCMoveBy : public CCActionInterval
{
public:
    bool initWithDuration(float duration,const CCPoint& deltaPosition);   //初始化序列
    virtual CCObject* copyWithZone(CCZone* pZone);
    virtual void startWithTarget(CCNode *pTarget);               //开始目标
    virtual CCActionInterval* reverse(void);                    
    virtual void update(float time);                         //更新

public:
    static CCMoveBy* create(float duration,const CCPoint& deltaPosition);
protected:
    CCPoint m_positionDelta;
    CCPoint m_startPosition;
    CCPoint m_previousPosition;
};

2、CCActionInterval：动作间隔类，继承自CCFiniteTimeAction

class CC_DLL CCActionInterval : public CCFiniteTimeAction
{
public:
    inline float getElapsed(void) { return m_elapsed; }       //获取从动作开始到目前已逝去的秒

    bool initWithDuration(float d);                         //初始化动作

    virtual bool isDone(void);                        //判断动作是否运行完成

    virtual CCObject* copyWithZone(CCZone* pZone);
    virtual void step(float dt);
    virtual void startWithTarget(CCNode *pTarget);
    /** returns a reversed action */
    virtual CCActionInterval* reverse(void);

public:
    static CCActionInterval* create(float d);

public:
    void setAmplitudeRate(float amp);    //设置和获得扩展
    float getAmplitudeRate(void);
protected:
    float m_elapsed;
    bool   m_bFirstTick;
};

3、CCFiniteTimeAction：有限时间动作，继承自CCAction

class CC_DLL CCFiniteTimeAction : public CCAction
{
public:
    CCFiniteTimeAction()
        : m_fDuration(0)
    {}
    virtual ~CCFiniteTimeAction(){}

    inline float getDuration(void) { return m_fDuration; }                         //设置和获得持续时间
    inline void setDuration(float duration) { m_fDuration = duration; }

    virtual CCFiniteTimeAction* reverse(void);           //返回一个倒退序列
protected:
    float m_fDuration;
};

4、CCCallFunc：动作回调函数处理类，继承自CCActionInstant

class CC_DLL CCCallFunc : public CCActionInstant
{
public:
    CCCallFunc()
        : m_pSelectorTarget(NULL),m_nScriptHandler(0),m_pCallFunc(NULL)
    {
    }
    virtual ~CCCallFunc();

    static CCCallFunc * create(CCObject* pSelectorTarget,SEL_CallFunc selector);       //创建和初始化相关函数
    static CCCallFunc * create(int nHandler);
    virtual bool initWithTarget(CCObject* pSelectorTarget);

    virtual void execute();                      //执行

    virtual void update(float time);            //更新
  
    CCObject * copyWithZone(CCZone *pZone);

    inline CCObject* getTargetCallback()     //设置和获得回调对象
    {
        return m_pSelectorTarget;
    }
    inline void setTargetCallback(CCObject* pSel)
    {
        if (pSel != m_pSelectorTarget)
        {
            CC_SAFE_RETAIN(pSel);
            CC_SAFE_RELEASE(m_pSelectorTarget);
            m_pSelectorTarget = pSel; 
        }
    }

    inline int getScriptHandler() { return m_nScriptHandler; };            //得到脚本句柄
protected:
    CCObject*   m_pSelectorTarget;

    int m_nScriptHandler;

    union
    {
        SEL_CallFunc    m_pCallFunc;
        SEL_CallFuncN    m_pCallFuncN;
        SEL_CallFuncND    m_pCallFuncND;
        SEL_CallFuncO   m_pCallFuncO;
    };
};

5、CC_SAFE_RETAIN：这个宏有意思，搞个一次循环

#define CC_SAFE_RETAIN(p)            do { if(p) { (p)->retain(); } } while(0)

6、CCActionInstant：立即动作类，继承自CCFiniteTimeAction，比较简陋

class CC_DLL CCActionInstant : public CCFiniteTimeAction
{
public:
    CCActionInstant();
    virtual ~CCActionInstant(){}
    
    virtual CCObject* copyWithZone(CCZone *pZone);
    virtual bool isDone(void);
    virtual void step(float dt);
    virtual void update(float time);
    virtual CCFiniteTimeAction * reverse(void);
};