iphone - 在游戏中移动 UIView 的最佳方式（无需用户交互）

Question

我正在寻找一种良好且流畅的方式来一次移动UIViews多个Screen。Action应该在检测Accelerometer到加速度时发生。我已经尝试过这种方式：

- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration{

    CGPoint ObjectPos = Object.center;

    ObjectPos.x -= acceleration.x;

    Object.center = ObjectPos;
}

（当然我添加了一些调整来改进运动检测），但总而言之，它仍然不是很流畅。

我希望核心动画有某种方式，但它似乎不适用于加速。

非常感谢您的帮助，谢谢！

Answer 1

我建议您阅读这篇文档：Isolating the Gravity Component from Acceleration Data和下面的部分，即“Isolating Instantaneous Motion from Acceleration Data”。

基本上，您需要过滤掉重力以获得平稳的运动。该链接提供了示例代码。

编辑：UIAccelerometer 在 iOS 5.0 中已被弃用，随附的文档似乎也不见了。

为了将来参考，我进行了一些挖掘，发现似乎是原始示例代码（source）的“复本”：

// This example uses a low-value filtering factor to generate a value that uses 10 percent of the
// unfiltered acceleration data and 90 percent of the previously filtered value


// Isolating the effects of gravity from accelerometer data
#define kFilteringFactor 0.1
- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration {
    // Use a basic low-pass filter to keep only the gravity component of each axis.
    accelX = (acceleration.x * kFilteringFactor) + (accelX * (1.0 - kFilteringFactor));
    accelY = (acceleration.y * kFilteringFactor) + (accelY * (1.0 - kFilteringFactor));
    accelZ = (acceleration.z * kFilteringFactor) + (accelZ * (1.0 - kFilteringFactor));
    // Use the acceleration data.
}

// shows a simplified high-pass filter computation with constant effect of gravity.

// Getting the instantaneous portion of movement from accelerometer data
#define kFilteringFactor 0.1
- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration {
    // Subtract the low-pass value from the current value to get a simplified high-pass filter
    accelX = acceleration.x - ( (acceleration.x * kFilteringFactor) + (accelX * (1.0 - kFilteringFactor)) );
    accelY = acceleration.y - ( (acceleration.y * kFilteringFactor) + (accelY * (1.0 - kFilteringFactor)) );
    accelZ = acceleration.z - ( (acceleration.z * kFilteringFactor) + (accelZ * (1.0 - kFilteringFactor)) );
    // Use the acceleration data.
}