On Tue, 2020-05-12 at 18:12 +0200, Hans de Goede wrote: > Hi, > > On 5/12/20 3:55 PM, Bastien Nocera wrote: > > Hey, > > > > I'm just dotting the is, and crossing the ts on a bunch of iio-sensor- > > proxy documentation and wanted to revisit the IIO documentation, > > compared to what Windows, and my implementation did. > > > > Does this: > > https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git/tree/Documentation/ABI/testing/sysfs-bus-iio#n1638 > > in particular the "Z" axis: > > "Z is perpendicular to the screen plane and positive out of the screen" > > > > match this: > > https://docs.microsoft.com/en-us/windows/uwp/devices-sensors/sensor-orientation > > "with the positive z-axis extending out from the device." > > Yes I believe that the 2 are stating the same, this is also how the > Z axis works on Android I believe. If you put a phone or tablet > flat on a table with the display up, then you will get a -1.0G or > -9.8 m/s² > reading since the gravity is pulling downwards (away from the front > of > the screen) with 1G. "extending out from the device" could mean away from the user, so away from the display, which would invert the Z axis compared to the IIO docs. I think that's the opposite of what was actually meant, but just to make doubly sure, I filed a bug against the Windows docs: https://github.com/MicrosoftDocs/windows-uwp/issues/2542 > > This Microsoft page didn't exist when I changed the code to "match > > Windows 10" in 2016: > > https://gitlab.freedesktop.org/hadess/iio-sensor-proxy/-/commit/35b6328cbdaa5efa30917c445962d64fd733fb02 > > > > (And just to double check, it seems that the other 2 axis do match in > > their definitions, right?) > > Yes I believe they do, and also again Android's definition. This seems to match indeed: https://developer.android.com/reference/android/hardware/SensorEvent
