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Reflection Capture Performance Issues

I have a quick question regarding Reflection Captures and how to optimize their performance better, if it’s possible to do so. I have read the documentation about reflection capture actors. I am getting a framerate drop of 15-20fps at 2560x1440p (from 120fps), slight dips in framerate on a 1080p monitor at 120fps, and fluctuations between 68-75fps in the Oculus Rift DK2 when I place a spherical or box reflection capture in my scene. Without this capture, the scene runs consistently at 120fps at 1440p, 1080p, and 75fps with no dips in the Rift. I had assumed that by the way the captures approximate reflection using just static objects and baked lighting, that it would be an almost negligible performance hit, so is this something I’m setting up wrong, or was I mistaken about them being cheap to render?

Some additional information -

The scene is being lit by a single directional light
GTX680 4GB
UE4.6.1

A follow up question - I really only need one object to appear somewhat convincingly reflective (the floor), so is there any way to only have the floor in this case use the reflection capture actor for the sake of performance?

I have also noticed similar drop in performance when using reflection captures.

tried disabling deferred lights?

stimpanzee apparently gained a bunch of frames in his car shader, here’s his thread:

That was impressive, wow. I just had a go at doing this and thought I was getting somewhere, but adding the SceneCaptureCube to the player makes it lose those additional scene capture parameters. I get the dropdown with the options, including the DeferredLighting checkbox, when it’s placed in the scene, but the dropdown isn’t there if I add it to the player Components, which I need to do to have the player movement update the reflection.

The performance drop is about the same as it was before when I was using other reflection techniques, although this time the framerate drop is only during player movement (if I turn off Capture Every Frame) which is better, but still unusable. If I lower the resolution of the capture significantly, it speeds things up but then the reflection looks too obviously low res. Thanks a lot for the link though, I didn’t actually know this was possible. I should spend more time in the Content Examples levels.

I’ll try to have the SceneCaptureCube update to the player’s position without putting it in the player Components, so I can take advantage of those additional options. If anyone has any other suggestions in the mean time I’d be happy to hear them.