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Bug XR Plugin Management - Built In Deferred + Single Pass no longer a option?

Discussion in 'VR' started by LVermeulen, Jun 25, 2021.

  1. LVermeulen

    LVermeulen

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    On switching to the XR Plugin Management from old XR Settings - there is no 'Single Pass' and only 'Single Pass Instanced'. But 'Single Pass Instance' does not work with the Deferred renderer with the built in pipeline

    Is the only option then to use MultiPass with Deferred, and being around 20%-30% slower than old XR Settings?
     
  2. LVermeulen

    LVermeulen

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    I can understand Deferred shouldn't be used for mobile VR/AR headsets - but for a PC VR game using Deferred this change completely breaks upgrading Unity versions
     
  3. the_real_apoxol

    the_real_apoxol

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    Which XR plugin are you using, Oculus, WinMR, OpenXR, etc?
     
  4. LVermeulen

    LVermeulen

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    SteamVR and Oculus. Haven't tried OpenXR yet
     
  5. the_real_apoxol

    the_real_apoxol

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    For SteamVR/OpenVR you will need to talk with Valve as it is supported by them. For the Oculus XR plugin there should be an option in the oculus settings for single pass I believe.
     
  6. LVermeulen

    LVermeulen

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    There being only Single Pass Instanced, and not working with Deferred, is the case for all XR plugins with the XR management system
     
  7. the_real_apoxol

    the_real_apoxol

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  8. LVermeulen

    LVermeulen

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    Yeah like I mentioned above Multipass is then the only option for Deferred - so then switching to this new XR Plugin management results in draw performance being 30% slower than old XR settings
     
  9. the_real_apoxol

    the_real_apoxol

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    Sorry I misunderstood, I thought you were saying there was only one option. I dont know why built-in deferred single-pass is not working with XR. I know HDRP is supported on XR but that probably doesnt help you. I will ask around to see if there is a known issue with built-in deferred/XR/single-pass.
     
    rasto61 likes this.
  10. the_real_apoxol

    the_real_apoxol

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    I started an internal discussion before the long weekend and it looks like built-in deferred Single-Pass should be working. If it is not working the best bet is to submit a bug using `Help -> Report a bug` and include a sample project and a description of what is not working. This way the graphics team can look into it.
     
  11. LVermeulen

    LVermeulen

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    On here: https://docs.unity3d.com/Manual/SinglePassInstancing.html - it mentions "Unity doesn’t support Single Pass Stereo Instancing in the Legacy Render Pipeline when using Deferred Rendering" (and again - we can't use non-instanced anymore with this new plugin management)

    I can submit a report though - what happens is the headset just shows complete white/dark
     
  12. rasto61

    rasto61

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    And there probably are no plans to support Single-Pass (non instanced), right?
     
  13. LVermeulen

    LVermeulen

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    If BuiltIn + SinglePass + Deferred is no longer possible - we didn't get any notice of that, and it impacts any released/indev VR games massively (a 30% performance hit for upgrading). The options are to either take the massive performance hit, switch rendering path to Forward, or switch render pipelines from Built In - all terrible

    The note that was added to that page about Deferred+SinglePassInstanced not working wasn't even there November of last year https://web.archive.org/web/20201101142946/https://docs.unity3d.com/Manual/SinglePassInstancing.html
     
    Last edited: Jul 7, 2021
  14. rasto61

    rasto61

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    Can you please confirm with the team, which version is correct? Either the footnote in the link above, (which says single pass instanced + deferred shouldnt work) or that single pass instanced + deferred should be supported (and if it doesnt, its probably a bug)
     
  15. the_real_apoxol

    the_real_apoxol

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    This is what I was told internally

    "We stopped supporting single-pass (double-wide) in XR SDK. We also don't really encourage using deferred for VR. They should be using forward + single-pass instancing on PC and forward + multiview on Quest"
     
  16. LVermeulen

    LVermeulen

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    So current VR projects that used BuiltIn+Deferred just should not update to Unity 2019/2020? There is no possibility of this changing? We had no indication that this wouldn't be supported in the future
     
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  17. the_real_apoxol

    the_real_apoxol

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    That is all the information I have at this time. You can submit a bug through `Help -> Report a bug` if you want to bring more attention to the issue.
     
  18. LVermeulen

    LVermeulen

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    Here are a few popular Unity VR PC games that I know use Deferred + Built in
    - Township Tale
    - NeosVR
    - Low FI

    It was never not recommended - just only for mobile
     
    Last edited: Jul 14, 2021
  19. rasto61

    rasto61

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    Yes, it was never not recommended, but they always recommended forward, mostly due to msaa. Imo deferred with taa is better too, and would hope to use deferred.
    But apoxol was only relaying what he was told.
    Can you submit a bug report please, so we see what they do?
     
  20. LVermeulen

    LVermeulen

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    Submitted a bug report, but it got closed by them as it wasn't considered a bug.
    I guess the new version breaking VR projects using Deferred is not a bug - despite nothing actually being deprecated.

    They haven't deprecated Built In - but are not going to fix this apparently. Yet another example of their SRP switch disaster
     
    Last edited: Jul 21, 2021
    ckriger likes this.
  21. LVermeulen

    LVermeulen

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    I understand there might be technical reasons why single pass Instanced + Deferred is not possible. But not including single pass non-instanced was a decision that Unity made - breaking all VR deferred projects without any notice.

    Deferred / built in were not deprecated - we had no indication that would not be supported in the future
     
    ckriger likes this.
  22. kro11

    kro11

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    Have the same issue, using VFX assets that don't work with Single Pass Instanced (doesn't work properly) and Multi Pass (Errors like "A multisampled texture being bound to a non-multisampled sampler. Disabling in order to avoid undefined behavior. Please use Texture2DMS in the shader.").
     
  23. unisip

    unisip

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    Bumping this. I have a game that works fine in VR using legacy deferred / single pass in Unity 2019.4.18. When I update this to Unity 2019.4.31, the rendering is broken. I am using legacy XR support. It is not clear why this rendering pass is now broken...
     
    arufolo-wellovate likes this.
  24. jjxtra

    jjxtra

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    Why is deferred + single pass instanced not an option? Some crazy technical reason or just too many options to support?
     
    arufolo-wellovate and ckriger like this.
  25. hONgzA

    hONgzA

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    Do you realize how restrictive that is and how much it negatively affects the visuals achievable? Are you trying to make VR dev community switch to Unreal? This is frankly outrageous.
     
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  26. DrInternet

    DrInternet

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    Two years later and still not fixed. They don't really give a frak about VR, do they?