cocos2dx打飞机项目笔记四：Enemy类和EnemyLayer类

Enemy类没什么内容，就create和init方法，根据参数来创建不同的敌机，头文件代码如下：

 //飞机的类型

 enum planeType {smallPlane, midPlane, bigPlane};

 class Enemy : public CCSprite

 {

 public:

     void loseLife();

     CC_SYNTHESIZE(float, m_speed, Speed);

     CC_SYNTHESIZE(int, m_life, Life);

     CC_SYNTHESIZE(int, m_score, Score);

     CC_SYNTHESIZE(planeType, m_type, Type);

     ~Enemy();

     virtual bool init(planeType type, CCTexture2D* texture);

     static Enemy* create(planeType type, CCTexture2D* texture);

 };

create和init方法实现如下：

Enemy* Enemy::create(planeType type, CCTexture2D* texture)

{

    Enemy *pRet = new Enemy();

    if (pRet && pRet->init(type, texture))

    {

        pRet->autorelease();

        return pRet;

    }

    else

    {

        delete pRet;

        pRet = NULL;

        return NULL;

    }

}

bool Enemy::init(planeType type, CCTexture2D* texture)

{

    bool bRet = false;

    do

    {

        const char* fileName;

        float score = ;

        int life = ;

        float speed = ;

        int random_speed = rand() %  + ;

        switch (type)

        {

        case bigPlane:

            fileName = "enemy3_n1.png";

            life = ;

            score = ;

            break;

        case midPlane:

            fileName = "enemy2.png";

            life = ;

            score = ;

            break;

        case smallPlane:

            fileName = "enemy1.png";

            life = ;

            score = ;

            break;

        default:

            break;

        }

;

        CC_BREAK_IF(!CCSprite::initWithSpriteFrameName(fileName));

        this->m_score = score;

        this->m_life = life;

        this->m_speed = *random_speed;

        this->m_type = type;

        bRet = true;

    } while ();

    return bRet;

}

EnemyLayer类则负责敌机除了创建之外的所有工作，包括开始启动创建方法、停止创建、移除敌机、敌机爆炸等。头文件：

 class EnemyLayer : public cocos2d::CCLayer

 {

 protected:

     CCSize designResolutionSize;

     CCSpriteBatchNode* batchNode;

 public:

     CCArray *m_enemys;

     EnemyLayer(void);

     ~EnemyLayer(void);

     virtual bool init();

     void startTakeEnemys(float dt);

     void stopTakeEnemy(void);

     void EnemyMoveToFinish(CCNode* pSender);

     void removeEnemy(CCNode* pTarget, void* enemy);

     void removeAllEnmeys();

     void addEnemy(float dt);

     void bomb(CCNode* pSender);

     CREATE_FUNC(EnemyLayer);

 };

敌机的创建和子弹不同，还记得子弹的创建我是保证屏幕上只有一粒子弹的吧，敌机则不然，固定每隔多少时间就会创建

 void EnemyLayer::startTakeEnemys(float dt)

 {

     float delay = 1.0f;//多少秒后调用

     float interval = 0.3f;//调用时间间隔

     this->schedule(schedule_selector(EnemyLayer::addEnemy), interval, kCCRepeatForever, delay);

 }

addEnemy和bomb方法实现：

 void EnemyLayer::addEnemy(float dt)

 {

     if (true)

     {

         int seed = ;

         int random_planeType = rand() % seed + ;//1~19

         planeType type;

         Enemy* enemy = NULL;

         //按概率随机生成大中小三种敌机，或者不产生

         //big

         if (random_planeType %  == )

         {

             type = bigPlane;

             SimpleAudioEngine::sharedEngine()->playEffect("music/big_spaceship_flying.wav",false);

         }

         //mid

         else if(random_planeType %  == )

         {

             type = midPlane;

         }

         //small

         else if(random_planeType %  == )

         {

             type = smallPlane;

         }

         // no

         else

         {

             return;

         }

         enemy = Enemy::create(type, this->batchNode->getTexture());

         //初始位置(随机)

         CCSize winSize = CCDirector::sharedDirector()->getWinSize();

         float x = rand() % (int)(winSize.width - (int)enemy->boundingBox().size.width * ) + enemy->boundingBox().size.width;

         float y = winSize.height - enemy->boundingBox().size.height/;

         CCPoint position = ccp(x,y);

         enemy->setPosition(position);

         this->m_enemys->addObject(enemy);

         batchNode->addChild(enemy);

         //敌机的运动轨迹CCDirector::sharedDirector()->getWinSize()

         float length = enemy->getContentSize().height + designResolutionSize.height;//飞行距离，超出屏幕即结束

         float velocity = /;//飞行速度：420pixel/sec

         float realMoveDuration = length/enemy->getSpeed();//飞行时间

         CCFiniteTimeAction* actionMove = CCMoveTo::create(realMoveDuration,ccp(x, -enemy->getContentSize().height));

         CCFiniteTimeAction* actionDone = CCCallFuncN::create(this,callfuncN_selector(EnemyLayer::EnemyMoveToFinish));//回调一个敌机结束处理函数

         CCSequence* sequence = CCSequence::create(actionMove,actionDone,NULL);

         enemy->runAction(sequence);

     }

 }

 void EnemyLayer::bomb(CCNode* pSender)

 {

     CCAnimation *animationBomb = NULL;

     Enemy *enemy = (Enemy*) pSender;

     char bombMusciName[];

     if (enemy->getType() == bigPlane)

     {

         sprintf(bombMusciName, "music/enemy3_down.wav");

         animationBomb = CCAnimationCache::sharedAnimationCache()->animationByName("animation_Enemy3Bomb");

     }

     else if(enemy->getType() == midPlane)

     {

         sprintf(bombMusciName, "music/enemy2_down.wav");

         animationBomb = CCAnimationCache::sharedAnimationCache()->animationByName("animation_Enemy2Bomb");

     }

     else if(enemy->getType() == smallPlane)

     {

         sprintf(bombMusciName, "music/enemy1_down.wav");

         animationBomb = CCAnimationCache::sharedAnimationCache()->animationByName("animation_Enemy1Bomb");

     }

     SimpleAudioEngine::sharedEngine()->playEffect(bombMusciName, false);//开始播放背景音效，false表示不循环

     CCActionInterval *action = CCScaleTo::create(0.5f, pSender->getScale() + 0.05f);

     CCCallFuncND *funcND = CCCallFuncND::create(this,callfuncND_selector(EnemyLayer::removeEnemy),(void*)pSender);

     CCFiniteTimeAction* seq = CCSequence::create(CCAnimate::create(animationBomb), funcND, NULL);

     pSender->stopAllActions();

     pSender->runAction(seq);

 }

可以看得出，这两个方法其实放到Enemy类里也很正常完全没问题的，这个要看coder想怎么写了。另外，敌机飞出屏幕外时的删除和被子弹打中时爆炸的回收是不同，差一个爆炸效果，而子弹在这两种情况的处理是一样的。