Why the massive difference in quality between VR and Normal in VR?

  • We're trying to run a project through VR on our Alienware dedicated VR laptop. We've thus far figured that the Glass material Enscape supplies (Glass Reflection 50) for example has massive implications on flickering whilst in VR (I think caused by the number of panes of glass, taken down to 1 it seems to work better). We're really struggling to be able to run the model in VR in Ultra as it stutters along as you're walking (Even though we have an optimal spec laptop to run it) so we've had to knock it down to High but the quality is almost that of Low quality rendering in VR.


    Why is there such a massive difference? It's really disappointing that we effectively can't run Ultra and even more disappointing that the difference is so massive from Ultra to High in VR.



    Normal Mode - High Quality



    VR Mode - High Quality

  • HI dan_noviun

    An official requirements is you need 90fps in order to reduce motion sickness and this has to be delivered in stereo approx 1k by 1k resolution in or higher.

    The headsets render internally with close to 4k resolution cause the rendered pictures gets bended for the human eyes.

    And for the higher resolutions total pixel throughput is higher than even 4k non VR.

    In Full HD with 60 FPS it's 124 Megapixel per second and the Rift and Vive need around 450 to 500 Megapixels per second.


    Latency must be kept to a minimum which is less forgiving to games and hardware requirement.

    Since it needs to be low latency and fast you can't rely on some performance tricks and have things look right especially in stereo.

    Field of view is also higher (approx 100 by 100) than in non VR where you have to render more stuff on screen.

    I mean basically you only have up to ~11ms per frame to render stereo instead of getting by with 16ms-33ms mono vision.


    The only way to reach this stats in real time rendering is to reduce the render quality.

  • Yes but that still doesn't answer his question of why there's such a big drop off from ultra to high quality settings in vr (with no global illumination on high), whereas in normal mode, high quality is still very close to ultra, with just simplified reflections but no loss of GI.

  • TowerPower  dan_noviun Caused by the official requirements for VR the render quality is reduced:

    • Ultra in VR equates to High in Non-VR
    • High in VR equates to Medium in Non-VR
  • Ok, so you just told us what's happening behind the scenes and the science and that's great, however, I think he wants to know is how to get his VR output to look similar to the Normal mode. Does he up the saturation in his VR settings? Or is there another setting that needs to be adjusted? - thanks.

  • Ok, so you just told us what's happening behind the scenes and the science and that's great, however, I think he wants to know is how to get his VR output to look similar to the Normal mode. Does he up the saturation in his VR settings? Or is there another setting that needs to be adjusted? - thanks.

    We did up the saturation slightly but it still didn't look as impressive. Other render packages seem to render out fine in VR such as Unreal Engine and Twinmotion however so it is odd that there's such a difference with Enscape.

  • I do understand your concern, however as Jonathan explained, the performance constraints of VR simply don't allow us to calculate precise indirect lighting with the same quality on current hardware yet. On a side note: Laptops are never optimal for VR use, as they don't reach the same performance levels powerful desktop machines do.


    We're currently evaluating multiple approaches for less detailed but very fast global illumination computation in VR, but did not come up with a satisfying solution yet. Our goal is to find a suitable fast solution independent of project scale that also doesn't require any manual tweaking - to keep Enscape a straightforward "one-click->awesome" tool ;)