COCOS2D-X 抖动效果 CCShake

游戏中屏幕抖动是一个非常炫的效果,那么在COCOS2D-X  中该怎么实现呢?

直接上代码:

CCShake.h

 #ifndef __SHAKE_H__
 #define __SHAKE_H__

 #include "cocos2d.h"
 USING_NS_CC;


 class CCShake : public cocos2d::CCActionInterval
 {
 public:
     CCShake();

     // Create the action with a time and a strength (same in x and y)
     static CCShake *create(float d, float strength );
     // Create the action with a time and strengths (different in x and y)
     static CCShake *createWithStrength(float d, float strength_x, float strength_y );
     bool initWithDuration(float d, float strength_x, float strength_y );

 protected:

     void startWithTarget(cocos2d::CCNode *pTarget);
     void update(float time);
     void stop(void);

     CCPoint m_StartPosition;


     // Strength of the action
     float m_strength_x, m_strength_y;
 };

 #endif //__SHAKE_H__

------------------------------------------------------------------------------------------------------------------------------------

CCShake.cpp

 #include "CCShake.h"
 #include "cocos2d.h"
 USING_NS_CC;

 // not really useful, but I like clean default constructors
 CCShake::CCShake() : m_strength_x(0), m_strength_y(0)
 {
 }

 CCShake *CCShake::create( float d, float strength )
 {
     // call other construction method with twice the same strength
     return createWithStrength( d, strength, strength );
 }

 CCShake *CCShake::createWithStrength(float duration, float strength_x, float strength_y)
 {
     CCShake *pRet = new CCShake();

     if (pRet && pRet->initWithDuration(duration, strength_x, strength_y))
     {
         pRet->autorelease();
     }
     else
     {
         CC_SAFE_DELETE(pRet);
     }


     return pRet;
 }

 bool CCShake::initWithDuration(float duration, float strength_x, float strength_y)
 {
     if (CCActionInterval::initWithDuration(duration))
     {
         m_strength_x = strength_x;
         m_strength_y = strength_y;

         return true;
     }

     return false;
 }

 // Helper function. I included it here so that you can compile the whole file
 // it returns a random value between min and max included
 static float fgRangeRand( float min, float max )
 {
     float rnd = ((float)rand() / (float)RAND_MAX);
     return rnd * (max - min) + min;
 }

 void CCShake::update(float dt)
 {
     float randx = fgRangeRand( -m_strength_x, m_strength_x ) * dt;
     float randy = fgRangeRand( -m_strength_y, m_strength_y ) * dt;

     // move the target to a shaked position
     m_pTarget->setPosition( ccpAdd(m_StartPosition, ccp( randx, randy)));
 }

 void CCShake::startWithTarget(CCNode *pTarget)
 {
     CCActionInterval::startWithTarget( pTarget );

     // save the initial position
     m_StartPosition=pTarget->getPosition();
 }

 void CCShake::stop(void)
 {
     // Action is done, reset clip position
     this->getTarget()->setPosition( m_StartPosition);

     CCActionInterval::stop();
 }

用法:


pSprite->runAction(CCShake::create(0.1f,10));
 pSprite:想抖动的物体


第一个参数是:抖动的时间

第一个参数是:抖动的幅度


注意

一个CCNode同时执行多个CCShake动作,或者一个CCShake没有完又执行一个CCShake的话就会出现问题,会出现偏移的现象!

解决方案:

1).不要同时执行多个CCShake动作.

2.自己外部记录这个CCNode的位置,执行完成后手动setPosition();