相关疑难解决方法(0)

还在BigNerdRanch iOS开发书上.

在Accelerometer章节中,他们首先实现加速度计跟踪,但它相当跳跃.然后,他们建议通过更改原始代码对其应用低通滤波器:

- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration
{
    HypnosisView *hv = (HypnosisView *)[self view];

    [hv setXShift:10.0 * [acceleration x]];
    [hv setYShift:10.0 * [acceleration y]];

    [hv setNeedsDisplay];
}

对此:

- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration
{
    HypnosisView *hv = (HypnosisView *)[self view];

    float xShift = [hv xShift] * 0.8 + [accel x] * 2.0;
    float yShift = [hv yShift] * 0.8 + [accel y] * 2.0;

    [hv setXShift:xShift];
    [hv setYShift:yShift];

    [hv setNeedsDisplay];
}

相当简单的问题:他们从哪里获得这些价值？我一直在查看文档,我发现了一些关于低通滤波器的东西,它建议使用以下代码:

   #define kFilteringFactor 0.1

- (void)accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration …