Compass magneticHeading problem in portrait mode (Android)

Unity Engine
1

Hi,

I am observing some weird behaviour of the compass magnetic heading value. When I hold the phone on landscape mode everything’s fine, but In portrait mode I have noticed some strange things…

When the phone is in portrait mode and held vertically (something like : -0.1< phone pitch < 0.1), the compass goes totally crazy… (meaning that I get wrong and very jerky values).

I have already submitted a question there with more details, but with no answer for now :
https://answers.unity.com/questions/1441113/compass-magneticheading-problem-in-portrait-mode-a.html

Could it be a Unity bug during the computation of magneticHeading and trueHeading from raw sensor data ?

Or am I missing something ?

Should I try to compute the magnetic heading on my own from rawVector and phone orientation or is it too complex ?

Thanks in advance for your answers,

Sylvain

1 Like
2

Try

transform.rotation = Quaternion.Slerp(transform.rotation, Quaternion.Euler(0, Input.compass.trueHeading, 0), Time.deltaTime * 2);
3

Hi, thanks for your reply.
I’ve just tried your suggestion, and it leads to the same problem.
It’s not very surprising as the bug comes from the Input.compass.trueHeading value itself.

4

I tried using Input.accelerometer, but my sensor always jitter. That is why I’m not using device accelerometer, locking it in certain orientation anf lerping trueHeading with deltaTime.

5

I’m seeing the same issue - fine when flat, random when held up. The only other major reference I’m seeing is your own StackOverflow issue atreyu - did you find a solution?

6

Hi, no unfortunately I did not find any solution. I gess that reading raw sensor data and calculating by yourself the magnetic heading value could work, but personally I don’t know how to compute this value.
Please let me know if you find any information about this problem. Thanks !

7

I guess filing a bug report is out of the question.

8

If your phone is pointed straight up, are you not pointing equally south, north, east, and west?

9

No problem when the phone is pointed straight up, the bug occurs when “-0.1< phone pitch < 0.1”, like if you take a selfy for example.