? ? ? ? 現在來實現敵機類
? ? ? ? 敵機和我方飛機相似，具有生命值、能夠發射子彈，并且有自己的運動軌跡。其實可以為它們設計一個共同的基類，這樣可以更方便擴展。
不同的敵機，應設置不同的標識、屬性
~~~
// 敵機生命值
const int ENEMY1_MAXLIFE = 1;
const int ENEMY2_MAXLIFE = 2;
const int ENEMY3_MAXLIFE = 5;
const int ENEMY4_MAXLIFE = 10;
// 敵機分數
const int ENEMY1_SCORE = 1;
const int ENEMY2_SCORE = 6;
const int ENEMY3_SCORE = 20;
const int ENEMY4_SCORE = 50;
~~~
~~~
// 敵機類型
enum EnemyType
{
Enemy1 = 1,
Enemy2,
Enemy3,
Enemy4,
};
~~~
頭文件中的主要函數
~~~
void setEnemyByType(EnemyType enType);
Sprite* getSprite();
int getLife();
void loseLife();
Rect getBoundingBox();
~~~
函數的實現
~~~
void Enemy::setEnemyByType(EnemyType enType)
{
switch (enType)
{
case Enemy1:
pEnemySprite = Sprite::createWithSpriteFrame(SpriteFrameCache::getInstance()->getSpriteFrameByName("enemy1.png"));
nLife = ENEMY1_MAXLIFE;
break;
case Enemy2:
pEnemySprite = Sprite::createWithSpriteFrame(SpriteFrameCache::getInstance()->getSpriteFrameByName("enemy2.png"));
nLife = ENEMY2_MAXLIFE;
break;
case Enemy3:
pEnemySprite = Sprite::createWithSpriteFrame(SpriteFrameCache::getInstance()->getSpriteFrameByName("enemy3.png"));
nLife = ENEMY3_MAXLIFE;
break;
case Enemy4:
pEnemySprite = Sprite::createWithSpriteFrame(SpriteFrameCache::getInstance()->getSpriteFrameByName("enemy4.png"));
nLife = ENEMY4_MAXLIFE;
break;
default:
return;
break;
}
this->addChild(pEnemySprite);
Size winSize = Director::getInstance()->getWinSize();
Size enemySize = pEnemySprite->getContentSize();
int minX = enemySize.width / 2;
int maxX = winSize.width - enemySize.width / 2;
int rangeX = maxX - minX;
int actualX = (rand() % rangeX) + minX;
// 設置敵機Node方位 Node包含Sprite
this->setPosition(Point(actualX, winSize.height - enemySize.height / 2));
}
bool Enemy::init()
{
bool pRet = true;
if (!Node::init())
{
pRet = false;
}
return pRet;
}
Sprite* Enemy::getSprite()
{
return pEnemySprite;
}
int Enemy::getLife()
{
return nLife;
}
void Enemy::loseLife()
{
--nLife;
}
Rect Enemy::getBoundingBox()
{
Rect rect = pEnemySprite->boundingBox();
Point pos = this->convertToWorldSpace(rect.origin);
Rect enemyRect(pos.x, pos.y, rect.size.width, rect.size.height);
return enemyRect;
}
~~~
根據敵機類型，綁定相應的圖片和生命值，對于我方飛機，如果想根據生命值來設定不同的飛機樣式，也可以通過此類方法。
