CCActionTween,CCAnimationCache源码分析

/**
@brief The delegate class for ActionTween.
@details If you want to use ActionTween on a node.
        You should implement the node follow these steps:
        1. The node should be inherit from ActionTweenDelegate.
        2. Override the virtual method updateTweenAction in the node.

        Then once you running ActionTween on the node, the method updateTweenAction will be incoked.
*/
/// 补间动画的委托类
/// 如果你想在一个节点上使用补间动画
/// 你应该按如下步骤实现：
/// 1.这个节点应该继承自补间动画委托类（ActionTweenDelegate）
/// 2.在节点中重载updateTweenAction方法
/// 然后，当你的节点执行补间动画的时候，updateTweenAction将被调用
class CC_DLL ActionTweenDelegate
{
public:
    /**
     * @js NA
     * @lua NA
     */
    virtual ~ActionTweenDelegate() {}

    /**
    @brief The callback function when ActionTween is running.
    @param value The new value of the specified key.
    @param key The key of property which should be updated.
    */
	/// 更新补间动画
    virtual void updateTweenAction(float value, const std::string& key) = 0;
};

/** ActionTween

 ActionTween is an action that lets you update any property of an object.
 For example, if you want to modify the "width" property of a target from 200 to 300 in 2 seconds, then:

 @code
     auto modifyWidth = ActionTween::create(2, "width", 200, 300);
     target->runAction(modifyWidth);
 @endcode

 Another example: ScaleTo action could be rewritten using PropertyAction:

 @code
     // scaleA and scaleB are equivalents
     auto scaleA = ScaleTo::create(2, 3);                 // (duration, to)
     auto scaleB = ActionTween::create(2, "scale", 1, 3); // (duration, key, from, to)
 @endcode

 @since v0.99.2
 */
 /// 补间动画
class CC_DLL ActionTween : public ActionInterval
{
public:
    /** 
     * @brief Create and initializes the action with the property name (key), and the from and to parameters.
     * @param duration The duration of the ActionTween. It's a value in seconds.
     * @param key The key of property which should be updated.
     * @param from The value of the specified property when the action begin.
     * @param to The value of the specified property when the action end.
     * @return If the creation success, return a pointer of ActionTween; otherwise, return nil.
     */
	 /// 创建一个补间动画
    static ActionTween* create(float duration, const std::string& key, float from, float to);

    // Overrides
    void startWithTarget(Node *target) override;
    void update(float dt) override;
    ActionTween* reverse() const override;
	ActionTween *clone() const override;
    
CC_CONSTRUCTOR_ACCESS:
    /** 
     * @brief Initializes the action with the property name (key), and the from and to parameters.
     * @param duration The duration of the ActionTween. It's a value in seconds.
     * @param key The key of property which should be updated.
     * @param from The value of the specified property when the action begin.
     * @param to The value of the specified property when the action end.
     * @return If the initialization success, return true; otherwise, return false.
     */
	 /// 初始化
    bool initWithDuration(float duration, const std::string& key, float from, float to);

protected:
    std::string       _key;
    float            _from, _to;
    float            _delta;
};

/** Singleton that manages the Animations.
It saves in a cache the animations. You should use this class if you want to save your animations in a cache.

Before v0.99.5, the recommend way was to save them on the Sprite. Since v0.99.5, you should use this class instead.

@since v0.99.5
@js cc.animationCache
*/
/// 动画快速缓存区
/// 这是一个单例，他保存了一个动画的缓存区，如果你想把你的动画存入缓存区，那么你应该用这个方法。
class CC_DLL AnimationCache : public Ref
{
public:
    /**
     * @js ctor
     */
    AnimationCache();
    /**
     * @js NA
     * @lua NA
     */
    ~AnimationCache();
    /** Returns the shared instance of the Animation cache 
	 @js NA
	*/
	/// 单例
    static AnimationCache* getInstance();

    /** Purges the cache. It releases all the Animation objects and the shared instance.
		@js NA
     */
	 /// 销毁单例
    static void destroyInstance();

    /** @deprecated Use getInstance() instead. */
    CC_DEPRECATED_ATTRIBUTE static AnimationCache* sharedAnimationCache() { return AnimationCache::getInstance(); }

    /** @deprecated Use destroyInstance() instead. */
    CC_DEPRECATED_ATTRIBUTE static void purgeSharedAnimationCache() { return AnimationCache::destroyInstance(); }

    bool init(void);

    /** Adds a Animation with a name.
     *
     * @param animation An animation.
     * @param name The name of animation.
     */
	 /// 添加动画
    void addAnimation(Animation *animation, const std::string& name);

    /** Deletes a Animation from the cache.
     *
     * @param name The name of animation.
     */
	 /// 移除动画
    void removeAnimation(const std::string& name);
    /** @deprecated. Use removeAnimation() instead
     * @js NA
     * @lua NA
     */
    CC_DEPRECATED_ATTRIBUTE void removeAnimationByName(const std::string& name){ removeAnimation(name);}

    /** Returns a Animation that was previously added.
     * If the name is not found it will return nil.
     * You should retain the returned copy if you are going to use it.
     *
     * @return A Animation that was previously added. If the name is not found it will return nil.
     */
	 /// 得到一个动画
    Animation* getAnimation(const std::string& name);
    /**
     * @deprecated. Use getAnimation() instead
     * @js NA
     * @lua NA
     */
    CC_DEPRECATED_ATTRIBUTE Animation* animationByName(const std::string& name){ return getAnimation(name); }

    /** Adds an animation from an NSDictionary.
     * Make sure that the frames were previously loaded in the SpriteFrameCache.
     * @param dictionary An NSDictionary.
     * @param plist The path of the relative file,it use to find the plist path for load SpriteFrames.
     * @since v1.1
	 @js NA
     */
	 /// 添加字典中的动画
    void addAnimationsWithDictionary(const ValueMap& dictionary,const std::string& plist);

    /** Adds an animation from a plist file.
     * Make sure that the frames were previously loaded in the SpriteFrameCache.
     * @since v1.1
     * @js addAnimations
     * @lua addAnimations
     * @param plist An animation from a plist file.
     */
	 /// 添加文件中的动画
    void addAnimationsWithFile(const std::string& plist);

private:
/// 解析
    void parseVersion1(const ValueMap& animations);
    void parseVersion2(const ValueMap& animations);

private:
    Map<std::string, Animation*> _animations;
    static AnimationCache* s_sharedAnimationCache;
};

// end of sprite_nodes group
/// @}