conjugate

Calculates and returns the conjugate of this quaternion.

The conjugate of a quaternion q = w + xi + yj + zk is q* = w - xi - yj - zk. It has the same scalar part (w) and negated vector part (-x, -y, -z).

For a unit quaternion (which is typically used to represent rotations), its conjugate is also its inverse (q* = q⁻¹).