This bug has been open for a long time, any chance it will be worked on? Thanks!


This is actually correct behaviour due to floating point errors.
The Rotators in UE have a range form -180 to 180. Due to the floating point errors, your values may be 180+/- a bit.
This also causes your Rotators to be imprecise and resulting in slightly different results.

We did actually look into this recently, but it’s quite tricky! We store rotations internally as quaternions, because they are much better for handling hierarchies of attachment etc. The down side of quats is that they are kind of impossible for a human to type in. So we display relative rotation as Euler angles (X/Y/Z), and convert when you enter. Unfortunately, there isn’t a unique euler<->quat mapping, so you can get odd stuff like this. We think the solution is to store rotation as a quat/rotator pair, and if you set it as euler, it derives the quat, and if you set as quat, it derives the euler. This is a fairly big change though, so we need to schedule some time to do it and test it all. Certainly near the top of our list though!