2016-03-16 21:32 GMT+01:00 Roderick Colenbrander <thunderbird2k@xxxxxxxxx>: > On Wed, Mar 16, 2016 at 12:09 PM, Clément VUCHENER > <clement.vuchener@xxxxxxxxx> wrote: >> 2016-03-16 16:26 GMT+01:00 David Herrmann <dh.herrmann@xxxxxxxxx>: >> >> Hi. >> >> I am writing a user-space driver for the steam controller and I was >> wondering how that would fit. The steam controller reports its >> absolute gyro data as a quaternion instead of three angles. Although, >> in the case of the steam controller, this data is meant to emulate >> other kind of devices from the driver, if applications started to use >> such an interface, it would be nice that the steam controller supports >> it. >> >>> >>> Thanks >>> David > > I haven't with the SteamController yet. Based on iFixit it has a > 3-axis gyro and 3-axis accelerometer. I guess the microcontroller > could be doing the quaternion calculations. Are you sure it is gyro > data and not maybe orientation data derived from gyro + accel? Try > spinning it around an axis and integrate the output in a script > (provided you knew the resolution in units per deg/s or rad/s). Yes, it is derived from gyro + accel. I did not read David's documentation correctly and I thought that ABS_GYRO_* was the absolute position (in rad or deg) but it is the speed (in deg/s). The speed data is also sent in the report although the quaternion is easier to use thanks to the calibration and integration done on the hardware. > > Some devices may use 1D or 2D sensors, so if for those just ABS_GYRO_X > / _Y for them, for a 4th dimension _W would make sense I guess. -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
