Skip to main content
motorsep
Inspiring
June 7, 2016

[Gear VR] UE 4.12 with HDR on running slow on Gear VR, but blazing fast on Daydream - why?!

While I didn't test it myself, the report is to be done by a trusted VR developer.

UE 4.12 now supports HDR on Gear VR. However, running with bloom on yields 30 fps. The same project running on the same phone with Cardboard yields 60 fps.

How is that possible?

Thanks
    This topic has been closed for replies.

    8 replies

    vrdaveb
    Inspiring
    June 7, 2016
    Thanks for reporting this. We'll take a look. Are you using the same eye buffer resolution for both cases?
    motorsepAuthor
    Inspiring
    June 7, 2016
    I am not really sure. Here is the OP and I will ask the person who tested to reply to your question:

    https://forums.unrealengine.com/showthread.php?113200-Has-anyone-tested-4-12-with-Gear-VR
    Anonymous
    June 7, 2016
    Hey vrdaveb,

    "Are you using the same eye buffer resolution for both cases? "

    I'm not sure about that how can I check? - I just did a pure gearvr export and compared to a pure daydream export of exactly the same project without changing any settings and both running on the same device S7 edge exynos chipset with UE4.12

    The performance difference is very large for my project at least. ~30FPS on the gearvr versus 60FPS on cardboard/daydream.

    Let me know if you require any further details

    vrdaveb
    Inspiring
    June 7, 2016
    What is the value of r.ScreenPercentage for each case?
    Anonymous
    June 7, 2016
    I definitely do not change that value at all but now wondering if UE4 changes it automatically under the hood so tested it out - not so easy to 'get' this value btw over wifi but here we go:

    daydream export: 100
    gearvr export: 100

    but I did notice this in the logs just before any image is shown:

    daydream export: "LogRenderer: Reallocating scene render targets to support 1280 x 720"
    gearvr export: "LogRenderer: Reallocating scene render targets to support 2560x1440"

    So I guess gearvr is just running in a higher resolution? Any idea how to change the resolution of my gearvr export down to 1280x720 to test this? As to be honest at first glance I didn't notice much difference from the resolution looking directly at the image on the display


    motorsepAuthor
    Inspiring
    June 8, 2016
    @vrdaveb @aussieburgerVR  I am wondering what's the verdict here :/
    Anonymous
    June 10, 2016
    Yeah UE4 is obviously exporting with different settings for both plugins that causes the performance differences.

    From https://forums.unrealengine.com/showthread.php?113468-GoogleVR-No-antialiasing-at-all&p=545612#post545612

    you can see googlevr has no AA whereas GearVR has MSAAx2 which would account for performance drop as well as being half the resolution.

    I'd like to know if there was a way to lower the resolution of gearvr exports a bit to get a trade off for better performance for more details ...

    motorsepAuthor
    Inspiring
    June 10, 2016
    Ooh, cheeky Google... 

    I tried scaling resolution and it doesn't seem to work outside of PIE (at least not on the device).
    Terms & ConditionsAccessibility statement