Mobile Gyroscope, make Camera always rotating towards zero point using Quaternion

Questions & Answers
1

So basically like this gif looks like
https://giphy.com/gifs/l0MYrjDwyvzLmj7Ms

^ left box represents gyroscope, right box represents player camera

here is the working code with eulerAngles,

gyroRotation = Input.gyro.attitude;
gyroRotation = Vector3.SlerpUnclamped(previousGyroscopeRotation, gyroRotation, fDamping * Time.deltaTime);
deltaRotation = (previousGyroscopeRotation - gyroRotation);

finalRotation = finalRotation - deltaRotation;

if (finalRotation.x != 0) 
    finalRotation.x = Mathf.LerpUnclamped(finalRotation.x, 0, 1 * Time.deltaTime);

if (finalRotation.y != 0)
    finalRotation.y = Mathf.LerpUnclamped(finalRotation.y, 0, 1 * Time.deltaTime);

if (finalRotation.z != 0)
    finalRotation.z = Mathf.LerpUnclamped(finalRotation.z, 0, 1 * Time.deltaTime);

transform.rotation = Quaternion.Slerp(transform.rotation, Quaternion.Euler(finalRotation), Time.deltaTime);

previousGyroscopeRotation = gyroRotation;

(but because of angle problems (ie: jumping from 350˙ to 10´ instead of 370)) internet suggested i use Quaternions, but have no idea how to achieve the same effect

transform.rotation = Quaternion.Slerp(transform.rotation, Input.gyro.attitude, Time.deltaTime);
transform.rotation = Quaternion.Slerp(transform.rotation, zeroPosition, Time.deltaTime);

this is the peak of my skills with Quaternions, if someone could shed some light on how to achieve this as simply as possible

2

To solve your Euler angle problems, you can use Mathf.LerpAngle which takes the jump from 360 to 0 into account. Also, the equivalent of (0,0,0) for rotation is Quaternion.identity, since quaternions can never be zero. I don’t think using angles is a bad idea, if you know what you’re doing. Simply changing Lerp to LerpAngle should probably fix any problems you have.

3

Ok So I’ve used Mathf.LerpAngle, it did fix the angle problems I’ve had,
but there were still the usual EulerAngle problems, where rotation x over ~75˙, y and z axis both flip to 180, and that again screwed the system up.

So I’ve research Quaternions, and basically few lines of code does exactly what I wanted with no problems :slight_smile:

gyroRotQuat = Input.gyro.attitude;
deltaRotQuat = (previousGyroscopeRotQuat * (Quaternion.Inverse(gyroRotQuat)));
finalRotQuat = finalRotQuat * (Quaternion.Inverse(deltaRotQuat));
transform.rotation = Quaternion.Slerp(transform.rotation, deltaRotQuat, Time.deltaTime);
previousGyroscopeRotQuat = gyroRotQuat;