摄像机跟随主角移动

void MPlayer::setMapPointByMplayer()
{
    Size visableSize = Director::getInstance()->getVisibleSize();
    Size mapTileNum = getGameMap()->getMapSize();
    Size tiledSize = getGameMap()->getTileSize();
    //世界大小 2.x CCSizeMake
    Size mapSize = Size(mapTileNum.width * tiledSize.width, mapTileNum.height * tiledSize.height);
    Point mplayerPoint = mSprite->getPosition();
    float x = mplayerPoint.x > visableSize.width / 4 ? mplayerPoint.x : visableSize.width / 4;
    x = x < mapSize.width - visableSize.width*.8 ? x : mapSize.width - visableSize.width*.8;
    float j = mapSize.width - visableSize.width*0.8;
    float y = mplayerPoint.y > visableSize.height / 4 ? mplayerPoint.y : visableSize.height / 4;
    y = y < mapSize.height / 2 ? y : mapSize.height / 2;
    Point desPoint = ccp(x, y);//目标点
    Point centerPoint = ccp(visableSize.width / 5, visableSize.height / 4);
    Point ritPoint = ccpSub(centerPoint, desPoint);
    getGameMap()->setPosition(ritPoint);
}