Lag between game & render


Don’t know if VR is the best thread for that anyway let’s try. I’m working on a new VR headset integration on UE4. Everything is working except the gyroscope tracking is not smooth and has some lag.
My HMD class inherit from IHeadMountedDisplay and I read gyroscope in UpdatePlayerCameraRotation by setting POV.Rotation

things are working, but it’s not smooth at all. “stat unit” says that I run a bit faster than 60hz ( about 15ms ). But everything appairs as the UpdatePlayerCameraRotation is called at a lower frequency. Is it possible?

Is it the right place to change the camera? I would like to change it at the lowest level possible, but I don’t know what’s the best place. ( at the beginning of renderthread should be perfect)

Second, when I’m in VR mode, “r.vsync 1” console command does not change anything ( fps won’t clamp to 60hz or 30hz ). How can I activate VSYNC in VR mode? ( r.vsync 1 works perfectly if I run the demo in the PC monitor)

Thanks in advance