Implementation of quaternion addition?

Question

Unity

Hello everyone,
It is necessary to correctly rotate in space so that there are no problems with the coincidence of the axes of the Euler angles. Accordingly, after reading the Unity3D manuals, I came across the built-in Qaternion class, which can translate from Euler angles to a quaternion, and vice versa.
Accordingly, the question is how to rotate the quaternion correctly if the input has the original quaternion (transfor.rotation) and the quaternion increment or the Euler angle increment.
Implementation for virtual reality for android.
Thanks for the answer.

Answer 1

Convert eulers to quaternions with Quaternion.Euler , and multiply by the resulting rotation:
transform.rotation *= Quaternion.Euler(0, 90, 0);