I am currently encountering an issue with the stereo layer implementation for the Oculus Rift, when using Unreal Engine 4.
In our game, we are using stereo layers to display the HUD elements, that are parented to the player pawn.
When a player snap turns 45 degrees, the pawn rotates, but the stereo layer appears to be drawn in their old position and orientation for a frame, before updating to their new location. This issue is not present when I have tested stereo layers on the Vive and the Quest.
I have created a small test project to demonstrate the issue.
The test project contains a basic pawn. This basic pawn has a sphere mesh projected 120cm infront of the player.
At the same location as the sphere, there is a stereo layer. Every 1 second, the pawn will update the rotation by 10 degree's.
Video of the StereoLayerTest project:
NOTE: To better highlight the effect of the delay, I set the frame-rate locked to 15 fps.
The issue can be seen at 90fps as well, it's just harder to clearly see, and record.
Link to StereoLayerTest Project (UE4.21):