CCActionCatmullRom(样条曲线动作 通过点数组自定义动作曲线)

.h

#ifndef __CCACTION_CATMULLROM_H__

#define __CCACTION_CATMULLROM_H__

#include <vector>

#include "CCActionInterval.h"

#include "base_nodes/CCNode.h"

#include "cocoa/CCGeometry.h"

NS_CC_BEGIN;

/** An Array that contain control points.

 Used by CCCardinalSplineTo and (By) and CCCatmullRomTo (and By) actions.

 */

class CC_DLL CCPointArray : public CCObject

{

public:

    

    /** creates and initializes a Points array with capacity（能力；容量；资格，地位） */

    static CCPointArray* create(unsigned int capacity);

    virtual ~CCPointArray();

    CCPointArray();

    

    /** initializes a Catmull Rom（瑞丽模式，一种抗锯齿过滤器）config with a capacity（性能） hint（提示 暗示 ） */

    bool initWithCapacity(unsigned int capacity);

    

    /** appends（附加） a control point */

    void addControlPoint(CCPoint controlPoint);

    

    /** inserts a controlPoint at index */

    void insertControlPoint(CCPoint &controlPoint, unsigned int index);

    

    /** replaces an existing controlPoint at index */

    void replaceControlPoint(CCPoint &controlPoint, unsigned int index);

    

    /** get the value of a controlPoint at a given index */

    CCPoint getControlPointAtIndex(unsigned int index);

    

    /** deletes a control point at a given index */

    void removeControlPointAtIndex(unsigned int index);

    

    /** returns the number of objects of the control point array */

    unsigned int count();//得到控制点数组大小

    

    /** returns a new copy of the array reversed. User is responsible for releasing this copy */

    CCPointArray* reverse();//返回一个相反的控制点数组 用户负责释放

    

    /** reverse the current control point array inline, without generating（生成） a new one */

    void reverseInline();//反转当前控制点数组

    

    virtual CCObject* copyWithZone(CCZone *zone);

    

    const std::vector<CCPoint*>* getControlPoints();//得到控制点数组指针

    void setControlPoints(std::vector<CCPoint*> *controlPoints);//设置控制点数组 参数是控制点指针

private:

    /** Array that contains the control points */

    std::vector<CCPoint*> *m_pControlPoints;  //制点数组指针

};

//参见下面的CCCardinalSplineBy(区别同 moveto 和moveby)

class CC_DLL CCCardinalSplineTo : public CCActionInterval

{

public:

    /** creates an action with a Cardinal Spline array of points and tension */

    static CCCardinalSplineTo* create(float duration, CCPointArray* points, float tension);

    virtual ~CCCardinalSplineTo();

    CCCardinalSplineTo();

    

    /** initializes the action with a duration and an array of points */

    bool initWithDuration(float duration, CCPointArray* points, float tension);

    

    // super virtual functions

    virtual CCCardinalSplineTo* copyWithZone(CCZone* pZone);

    virtual void startWithTarget(CCNode *pTarget);

    virtual void update(float time);

    virtual CCActionInterval* reverse();

    

    virtual void updatePosition(CCPoint &newPos);

    

    inline CCPointArray* getPoints() { return m_pPoints; }

    inline void  setPoints(CCPointArray* points) 

    {

        CC_SAFE_RETAIN(points);

        CC_SAFE_RELEASE(m_pPoints);

        m_pPoints = points;

    }

    

protected:

    /** Array of control points */

    CCPointArray *m_pPoints;

    float m_fDeltaT;

    float m_fTension;

    CCPointm_previousPosition;

    CCPointm_accumulatedDiff;

};

/////////////////////////

CCCardinalSplineBy概念

这个类是样条曲线动作，其创建函数CCCardinalSplineBy::create(float duration, cocos2d::CCPointArray *points, float tension)；

中duration是时间间隔，points是控制点列表，tension是松紧程度。tension==1时，样条线是分段直线。tension<1向外松弛弯

曲，tension>1向内缩紧弯曲。By动作是以当前坐标为新坐标原点。

CCCardinalSplineBy示例–为同一组控制点实现不同的移动路径

///////////////////

class CC_DLL CCCardinalSplineBy : public CCCardinalSplineTo 

{

public:

    

    /** creates an action with a Cardinal Spline array of points and tension */

//1、时间间隔 2、控制点列表 3、松紧程度。tension==1时，样条线是分段直线。tension<1向外松弛弯

//曲，tension>1向内缩紧弯曲。By动作是以当前坐标为新坐标原点。

    static CCCardinalSplineBy* create(float duration, CCPointArray* points, float tension);

    CCCardinalSplineBy();

    

    virtual void startWithTarget(CCNode *pTarget);

    virtual CCActionInterval* reverse();

    virtual void updatePosition(CCPoint &newPos);

protected:

    CCPoint m_startPosition;

};

/** An action that moves the target with a CatmullRom curve to a destination point.

 A Catmull Rom is a Cardinal Spline with a tension of 0.5.

 */

class CC_DLL CCCatmullRomTo : public CCCardinalSplineTo//tension of 0.5.

{

public:

    

    /** creates an action with a Cardinal Spline array of points and tension */

    static CCCatmullRomTo* create(float dt, CCPointArray* points);

    /** initializes the action with a duration and an array of points */

    bool initWithDuration(float dt, CCPointArray* points);

};

/** An action that moves the target with a CatmullRom curve by a certain distance.

 A Catmull Rom is a Cardinal Spline with a tension of 0.5.

 http://en.wikipedia.org/wiki/Cubic_Hermite_spline#Catmull.E2.80.93Rom_spline

 @ingroup Actions

 */

class CC_DLL CCCatmullRomBy : public CCCardinalSplineBy

{

public:

    

    /** creates an action with a Cardinal Spline array of points and tension */

    static CCCatmullRomBy* create(float dt, CCPointArray* points);

    /** initializes the action with a duration and an array of points */

    bool initWithDuration(float dt, CCPointArray* points);

};

/** Returns the Cardinal Spline position for a given set of control points, tension and time */

extern CC_DLL CCPoint ccCardinalSplineAt(CCPoint &p0, CCPoint &p1, CCPoint &p2, CCPoint &p3, float tension, float t);

// end of actions group

/// @}

NS_CC_END;

#endif // __CCACTION_CATMULLROM_H__