cocos2dx 3如何摇屏？答案

【问题标题】：How to shake screen in cocos2dx 3?cocos2dx 3如何摇屏？
【发布时间】：2014-10-24 15:38:43
【问题描述】：

我正在尝试摇晃整个屏幕。以前我使用下面的编码：

Shaky3D *shake = Shaky3D::create(0.2f, Size(1,1), 10, false);
this->runAction(Sequence::create(shake, NULL));

但现在我使用的是 Cocos2d-x 3.2，我尝试了以下方法，但它不起作用。我应该如何正确编码？谢谢。

NodeGrid* nodeGrid = NodeGrid::create();
this->addChild(nodeGrid);

auto shake = Shaky3D::create(0.2f, Size(1,1), 20, false);
nodeGrid->runAction(Sequence::create(shake, NULL));

【问题讨论】：

标签： cocos2d-x cocos2d-x-3.0

【解决方案1】：

嗯，我找到了另一种方法。

void GameScene::shakeScreen(float dt)
{
    float randx = rangeRandom( -50.0f, 50.0 );
    float randy = rangeRandom( -50.0f, 50.0 );

    this->setPosition(Point(randx, randy));
    this->setPosition(Point(initialPos.x + randx, initialPos.y + randy));

    SET_SHAKE_DURATION -= 1;

    if (SET_SHAKE_DURATION <= 0)
    {
        this->setPosition(Point(initialPos.x, initialPos.y));
        this->unschedule(schedule_selector(GameScene::shakeScreen));
    }
}

float GameScene::rangeRandom( float min, float max )
{
    float rnd = ((float)rand()/(float)RAND_MAX);
    return rnd*(max-min)+min;
}

【讨论】：

【解决方案2】：

这里有一个更好的（来自统一）

float noise(int x, int y) {
    int n = x + y * 57;
    n = (n << 13) ^ n;
    return (1.0 - ((n * ((n * n * 15731) + 789221) + 1376312589) & 0x7fffffff) / 1073741824.0);
}

bool TestScene::onTouchBegan(cocos2d::Touch *touch, cocos2d::Event *event) {

//experiment more with these four values to get a rough or smooth effect!
    float interval = 0.f;
    float duration = 0.5f;
    float speed = 2.0f;
    float magnitude = 1.0f;

    static float elapsed = 0.f;

    this->schedule([=](float dt) {
        float randomStart = random(-1000.0f, 1000.0f);
        elapsed += dt;

        float percentComplete = elapsed / duration;

// We want to reduce the shake from full power to 0 starting half way through
        float damper = 1.0f - clampf(2.0f * percentComplete - 1.0f, 0.0f, 1.0f);

// Calculate the noise parameter starting randomly and going as fast as speed allows
        float alpha = randomStart + speed * percentComplete;

        // map noise to [-1, 1]
        float x = noise(alpha, 0.0f) * 2.0f - 1.0f;
        float y = noise(0.0f, alpha) * 2.0f - 1.0f;

        x *= magnitude * damper;
        y *= magnitude * damper;
        this->setPosition(x, y);

        if (elapsed >= duration)
        {
            elapsed = 0;
            this->unschedule("Shake");
            this->setPosition(Vec2::ZERO);
        }

    }, interval, CC_REPEAT_FOREVER, 0.f, "Shake");

    return true;
}

【讨论】：