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Latency in Camera translation on the Vive.

Hi I noticed considerable latency in camera translation when using the Vive both in Pie and in pure game. Tested this in 4.11 and 4.12 on bot the regular and beta branch of SteamVR.
https://youtube.com/watch?v=PL8ptJ3R7Wc
This latency seems to persist for all tick groups for the camera (component). I am using the SteamVR overlay just to visualise it as the controllers are just resting on a surface. The problem is the latency, not the discrepancy per se, that is just a side effect.
The issue is not there in the VR Editor in 4.12 and as I discovered later in some specific games like The Brookhaven Experiment either. But most UE demos seem to have it.

The issue seems not to be present on the Rift.

Any advice on tracking down the cause would be much appreciated!

This Answerhub post seems to be dealign with the same issue: https://answers.unrealengine.com/questions/422372/huge-latency-with-htc-vive-on-412-preview.html

Edit Upon further investigation I narrowed it down to having an active camera component in the pawn. If i disable it the latency vanishes.

I was able to reproduce the issue, and good news is the fix is already in 4.12! The issue is fixed in github (the fix is fairly straightforward to apply to 4.11 manually). The issue was logged as UE-31687

https://github.com/EpicGames/UnrealEngine/commit/6b377c8f33d669f64779561d050d141513a44797

The fix won’t make it to the binary version until 4.12.2, so if you want the fix sooner than later just head over to github :slight_smile: