cocos2d-x 3.2 移动游戏背景和精灵

1，先新增监听事件

auto listener = EventListenerTouchOneByOne::create();
	listener->setSwallowTouches(true);
	listener->onTouchBegan = CC_CALLBACK_2(StartGame::onTouchBegan, this);
	listener->onTouchMoved = CC_CALLBACK_2(StartGame::onTouchMoved, this);
	listener->onTouchEnded = CC_CALLBACK_2(StartGame::onTouchEnded, this);
	_eventDispatcher->addEventListenerWithSceneGraphPriority(listener, this);

2，监听的方法回调函数实现

bool StartGame::onTouchBegan(Touch* touch, Event* event)
{
    Point touchLocation = this->convertTouchToNodeSpace(touch);
    this->selectSpriteForTouch(touchLocation);
    return true;
}

void StartGame::onTouchMoved(Touch* touch, Event* event)
{
	Point touchLocation = this->convertTouchToNodeSpace(touch);
    Point oldTouchLocation = touch->getPreviousLocation();
    oldTouchLocation = this->convertToNodeSpace(oldTouchLocation);
    Point translation = touchLocation - oldTouchLocation;//获取移动的距离

	CCLog("touchLocation--------------------%d-------%d",touchLocation.x,touchLocation.y);
	CCLog("oldTouchLocation--------------------%d-------%d",oldTouchLocation.x,oldTouchLocation.y);
	CCLog("translation--------------------%d-------%d",translation.x,translation.y);

    this->boundLayerPos(translation);//背景移动函数

    //this->panForTranslation(translation);//精灵移动函数

}

void StartGame::onTouchEnded(Touch* touch, Event* event)
{
}

3，方法实现

这个事背景事件，在init里面加载一张背景图片

void StartGame::boundLayerPos(Point newtouch)
{
    Size winSize = Director::getInstance()->getWinSize();
	Point newPos = this->getPosition() + newtouch;
	auto map = getChildByTag(102); //这里获取背景图片

    newPos.x = MIN(newPos.x, 0);
    newPos.x = MAX(newPos.x, -map->getContentSize().width+winSize.width);

    newPos.y = MIN(newPos.y,0);
	newPos.y = MAX(newPos.y, -map->getContentSize().height + winSize.height);

    this->setPosition(newPos);
}

精灵移动方法实现

在init里面加载一个精灵

void StartGame::panForTranslation(Point translation)
{
	auto sprite = getChildByTag(101);//获取精灵
    Point newPos = sprite->getPosition() + translation;
    sprite->setPosition(newPos);

}

这就ok了

精灵或者是背景图片移动都是在触屏监听事件的onTouchMoved(Touch* touch,Event * event)里面获取原触屏点和移动以后的触屏点，得到他们的差值，给精灵或者背景图片重新定位setPosition(Point * point),就完成了背景和精灵的移动（背景图片要判断边界值得）

注意，Node可通过函数getBoundingBox返回精灵的边界矩形。这比你自己手动计算精灵的边界矩形要好多了。因为，第一，它更简单;第二，它考虑了精灵的位置坐标变换。（比如锚点变了，要执行相应的矩阵变换，具体可以参考源代码，这些就不再细说了。）

点击选中的时候可以先让精灵做一些动作，这里是闪烁

void StartGame::selectSpriteForTouch(Point touchLocation)
{
	auto sprite = getChildByTag(101);

    if ( sprite->getBoundingBox().containsPoint(touchLocation) )
    {
            auto blink = CCBlink::create(2.0f,5);
			sprite->runAction(blink);
    }

}