Android getOrientation()返回方位角，是正数还是负数? [英] Android getOrientation() returns azimuth, positive or negative?

问题描述

假设:将手机放平(与地面平行).

Assumption: the phone is held flat (parallel with the ground).

我正在使用 getRotationMatrix()和 getOrientation(float [] R，float []值)来获取方位角.在此假设下，方位角就是 values [0] .

I am using getRotationMatrix() and getOrientation (float[] R, float[] values) to get the azimuth. Under this assumption, the azimuth is simply values[0].

以上所有三个角度均以弧度表示，正方向以逆时针方向.

All three angles above are in radians and positive in the counter-clockwise direction.

然后我检查了一下，当手机的y轴指向北时，方位角确实为 0 .

Then I checked, when my phone's y axis points to the North, the azimuth is indeed 0.

但是，问题来了:当我的手机的y轴指向 West 时，即我将手机逆时针旋转，使其从北向西指向，方位角是负！

However, here comes the problem: when my phone's y axis points to West, i.e. I rotated my phone counter-clockwise to make it point from North to West, the azimuth is negative!

从北方逆时针旋转角度不应该为正吗?

哪里出问题了?

推荐答案

否，如果Z的正方向指向天空，则当y轴指向West时，该角度为正.但是getOrientation中使用的坐标Z的正方向指向地球，因此，现在看来逆时针变为顺时针，因此West为负.

No, if the positive direction of Z points to the sky then when y axis points to West then the angle is positive. But the coordinate used in getOrientation the positive direction of Z points down to the earth, thus now what seems counter-clockwise becomes clockwise, so West is negative.

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