I rely on quaternions, since I am working on a space game with full 6 DOF as well as other projects, I even need it just to do aim offsets that replicate over network without doing weird twirls periodically!
**FQuat::Slerp **is your friend! Spherical Interpolation!
Slerp is the only way I can ensure networked replicated rotations for all proxies interpolate correctly!
You can just use FQuats like you would Rotators, by converting
FQuat SomeQuat
FRotator = SomeQuat.Rotator()
FRotator SomeRot
FQuat = SomeRot.Quaternion()
Summary: you can define your quats as the familiar FRotator and then convert, but do all operations on the quaternions, and just convert the result back to FRotator as needed
or many UE4 functions will accept FQuat directly, so you dont have to convert back.
like FTransform::SetRotation()
Rama