I am sort of back to square one with performance on Gear VR, except this time performance drop is significant and happens for unknown reasons. Drawcalls are ~20, ~10k tris, and fps drop happens (was using stat SceneRendering in PIE).
It’s a new project with new assets (Infinity Blade, optimized even more):
Basically I have a terrain (static mesh; in chunks, each with LODs) with a few rocks on top of it (with LODs; base LOD is no more than 2k tris). If I stand in a way that all rocks are in the view, I get my ~59 fps (as if it’s an empty scene). However, if I get close to any rock so that it takes up whole screen, fps drops to 40-something.
Thanks beforehand
P.S. I can privately share the project with Epic staff (I am guessing PM on UE4 forums would be fine?)
Basically when I look up where trace hits nothing, performance is good (considering that video capture chugs fps). Tracing far away from player is pretty good too. However, as I look closer and closer to player’s location (trace hits closer to player), performance degrades and at some point it drops to minimum (yellow fps counter).
I am using capsule trace (so that player can’t teleport where it will get stuck).
This issue doesn’t seem to appear in PIE.
I also don’t recall having this issue with 4.11.2 (currently using 4.12.4)
It definitely an issue with capsule trace. I did “stat startfile” on the device and will check profiling results today.
The odd thing was that when I used “stat startfile” on the device, all performance issues went away. I didn’t have fps dips as I have when running normally.
Dithered LOD transition is what kills performance on Gear VR.
This means neither HISMCs nor foliage can be used on Gear VR, unless Epic will add an option to disable dithered LOD transition specifically for mobile VR (in addition to adding support for static lighting for HISMCs and foliage).