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SSGI for HDRP?

Discussion in 'Graphics Experimental Previews' started by passeridaepc, Jun 28, 2020.

  1. passeridaepc

    passeridaepc

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    Jun 16, 2019
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    Hi, I've been seeing pieces of info about SSGI being developed for HDRP for some time now. Is there a plan to release it in the near future? Like for HDRP 10.

    There's also some "highly experimental" thing called Probe Volumes (not the LPPV ones), which seems to be designed to produce some kind of GI as well. Can someone explain what it is, exactly?

    Thanks.
     
  2. jjejj87

    jjejj87

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    I'd very much appreciate the explanation as well.
     
  3. BATTLEKOT

    BATTLEKOT

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    Oct 2, 2016
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    Lets wait for alpha version of SSGI.
     
  4. Grimreaper358

    Grimreaper358

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    I've been using it for a little. Basically it is tied in with raytracing so you would need a card that can run raytracing to be able to use ScreenSpace GI.


    Probe Volumes - Controls are the same as any other volume/probe
    You can enable this if you are using 2020.1 beta or 2020.2 alpha and the latest HDRP 9.0.0 preview package

    I've also been using probe volumes and it's basically as its name says. It's a volume of probes that you can use to generate GI for the area it's placed. Note: You are still baking the GI for the probes (CPU or GPU lightmapper) it's just now being stored in a probe volume/grid so you don't need Lightmap UVs for it to work. since it isn't baking a texture it bakes a lot faster. I was getting a 12-second or less bake time on a decent size scene with a few probe volumes. To enable it you have to edit a script and do a few more steps. It walks you through the setup but what it doesn't tell you is (You also need to enable probe volumes in the Default Frame settings) for you to see anything in game/scene.

    Probe Volume GI

    upload_2020-7-1_17-31-42.png

    upload_2020-7-1_17-32-14.png
     
    Lex4art, sendspace, BATTLEKOT and 2 others like this.
  5. passeridaepc

    passeridaepc

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    You've been using SSGI? How did you get access to it?

    Hmm...are you 100% sure? SSGI in other engines as well as many unofficial SSGI solutions for built-in pipeline in Unity do not require any RTX hardware acceleration...


    Did you by any chance make a comparison between Probe Volume and regular lightmaps? Probe Volumes from what I know tend to be way less accurate than lightmaps.
     
  6. Grimreaper358

    Grimreaper358

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    SSGI still needs some work to be ready to use. If you get the latest package in for HDRP in the package manager (9.0.0-preview.33) you can enable it on the pipeline asset as well as in the Frame settings.
    (It might be in older 9.x versions but I'm not sure I haven't used those, I mainly use 2020.2 alpha and various HDRP dev branches from Github)


    Yea, my bad, you have it in both modes. With RTX enabled you can also add SSGI on top of that, as well as just using it alone in a non-RTX/DX12 project.


    Yea, I did this with another project. Basically it depends. Same as you can have low-quality lightmaps with low resolution and large texels, you can have a low-quality Light Probe Volume bake with low probe samples (amount of spheres in the debug view in the post above) so it depends on how many probes you want to use.
     
    passeridaepc and BATTLEKOT like this.
  7. Onat-H

    Onat-H

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    Mar 11, 2015
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    So what exactly is the difference between the probe volume and regular light probes then? (Besides of faster setup I guess...)
     
  8. Bordeaux_Fox

    Bordeaux_Fox

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    Nov 14, 2018
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    I tried SSGI and it's awful. Despite the obvious noise and stripe artefacts it also creates some sort of white Occlusion on every edge. Very strange. (RTX 2060)

    I'm really scared about the planned schedule for the new Realtime GI seeing the current progress. It is planned for 2021, right?
     

    Attached Files:

  9. passeridaepc

    passeridaepc

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    Hmm...this SSGI does look really weird. But there are some pretty decent tests on Github. I wonder, how they've done them. Maybe there's a newer and better version off SSGI that hasn't been released yet. I hope.
     
  10. Grimreaper358

    Grimreaper358

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    Probe Volume - Bakes your GI into the probes and require your geometry to have no Lightmap UV or lightmaps baked.
    Light Probes - Samples the lightmaps baked for your geometry to be able to project that to dynamic objects in the scene.
     
  11. Grimreaper358

    Grimreaper358

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    Apr 8, 2013
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    It's not a released system yet, It's still being worked on. It just got initially included in this early version of the Render Pipeline.

    When 2020.1 is released is when you should really be looking at it. If you are willing to use the 2020.2 alpha you can use the latest version they are working on from GitHub to better see where it is. That's what will be backported to the 2020.1 versions.
     
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