c++ - cocos2dx 有时会忽略 setposition()

Question

我有一个将对象放入屏幕的循环。但出于某种原因，一些对象虽然在 printf 中打印了正确的坐标，但在 (0,0) 点，就好像他没有完成设置它的位置一样。

for (int i =0 ; i < 7; i++) {
        float rand = rand_0_1();
        if (rand <= numberOfNewsObjects/numeroTotal) {
            numberOfNewsObjects--;
            auto  *box = BGObstacle::create();
            box->getPhysicsBody()->setCategoryBitmask((int)PhysicsCategory::Obstacle);
            box->getPhysicsBody()->setContactTestBitmask(true);
            box->setPosition(Vec2((i * (42+3))+4 + 21,(8 * (42+3))+4 + 100 + 21));
            printf("x: %f  y: %f",box->getPosition().x , box->getPosition().y);
            mainLayer->addChild(box, 1);
            arrayOfObstacle.pushBack(box);
            printf(" +%d\n ", i);
        }
}

BGObstacle 是DrawNode 的子类

用这个解决

 cocos2d::Director::getInstance()->getScheduler()->performFunctionInCocosThread(‌​[=](){   for (int i =0 ; i < 7; i++) {
            float rand = rand_0_1();
            if (rand <= numberOfNewsObjects/numeroTotal) {
                numberOfNewsObjects--;
                auto  *box = BGObstacle::create();
                box->getPhysicsBody()->setCategoryBitmask((int)PhysicsCategory::Obstacle);
                box->getPhysicsBody()->setContactTestBitmask(true);
                box->setPosition(Vec2((i * (42+3))+4 + 21,(8 * (42+3))+4 + 100 + 21));
                printf("x: %f  y: %f",box->getPosition().x , box->getPosition().y);
                mainLayer->addChild(box, 1);
                arrayOfObstacle.pushBack(box);
                printf(" +%d\n ", i);
            }
    }
});

Answer 1

您的代码应该没问题。你在这个功能之外改变他们的位置吗？我会考虑重写 BGObstacle::setPosition(float x, float y):

BGObstacle::setPosition(float x, float y){
    assert(Vec2(x, y).length()>0.001f);
    Sprite::setPosition(x, y);
}

当任何 BGObstacle 移动到 (0, 0) 时，游戏将被中断，您可以看到调用堆栈。