Cocos2d-x 3.0多线程异步加载资源实例

// AppDelegate.cpp
bool AppDelegate::applicationDidFinishLaunching() {
    … …
    FlashScene* scene = FlashScene::create();
    pDirector->runWithScene(scene);

在FlashScene init时，我们创建一个Resource Load Thread，我们用一个ResourceLoadIndicator作为渲染线程与Worker线程之间交互的媒介。

//FlashScene.h

struct ResourceLoadIndicator {
    pthread_mutex_t mutex;
    bool load_done;
    void *context;
};

class FlashScene : public Scene
{
public:
    FlashScene(void);
    ~FlashScene(void);

    virtual bool init();

    CREATE_FUNC(FlashScene);
    bool getResourceLoadIndicator();
    void setResourceLoadIndicator(bool flag);

private:
     void updateScene(float dt);

private:
     ResourceLoadIndicator rli;
};

// FlashScene.cpp
bool FlashScene::init()
{
    bool bRet = false;
    do {
        CC_BREAK_IF(!CCScene::init());
        Size winSize = Director::getInstance()->getWinSize();

        //FlashScene自己的资源只能同步加载了
        Sprite *bg = Sprite::create("FlashSceenBg.png");
        CC_BREAK_IF(!bg);
        bg->setPosition(ccp(winSize.width/2, winSize.height/2));
        this->addChild(bg, 0);

        this->schedule(schedule_selector(FlashScene::updateScene)
                       , 0.01f);

        //start the resource loading thread
        rli.load_done = false;
        rli.context = (void*)this;
        pthread_mutex_init(&rli.mutex, NULL);
        pthread_attr_t attr;
        pthread_attr_init(&attr);
        pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);
        pthread_t thread;
        pthread_create(&thread, &attr,
                    resource_load_thread_entry, &rli);

        bRet=true;
    } while(0);

    return bRet;
}

static void* resource_load_thread_entry(void* param)
{
    AppDelegate *app = (AppDelegate*)Application::getInstance();
    ResourceLoadIndicator *rli = (ResourceLoadIndicator*)param;
    FlashScene *scene = (FlashScene*)rli->context;

    //load music effect resource
    … …

    //init from config files
    … …

    //load images data in worker thread
    SpriteFrameCache::getInstance()->addSpriteFramesWithFile(
                                       "All-Sprites.plist");
    … …

    //set loading done
    scene->setResourceLoadIndicator(true);
    return NULL;
}

bool FlashScene::getResourceLoadIndicator()
{
    bool flag;
    pthread_mutex_lock(&rli.mutex);
    flag = rli.load_done;
    pthread_mutex_unlock(&rli.mutex);
    return flag;
}

void FlashScene::setResourceLoadIndicator(bool flag)
{
    pthread_mutex_lock(&rli.mutex);
    rli.load_done = flag;
    pthread_mutex_unlock(&rli.mutex);
    return;
}