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Feedback Bad SSGI and SSR performance and noise

Discussion in 'SRP Dev Blitz Day 2022 - Q&A' started by Deleted User, Sep 29, 2022.

  1. Deleted User

    Deleted User

    Guest

    Last edited by a moderator: Sep 29, 2022
    Deleted User, Sep 29, 2022
    #1

  2. Deleted User

    Deleted User

    Guest

    Tested on 1650, SSGI halves the performance in some scenes and SSR is heavy too, takes out 1/4th of performance
     
    Deleted User, Sep 29, 2022
    #2

  3. Deleted User

    Deleted User

    Guest

    Deleted User, Sep 29, 2022
    #3

  4. auzaiffe

    auzaiffe

    Unity Technologies

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    Due to the nature of the algorithm, SSGI is going to be very expensive, no matter what, especially on lower end graphics cards like the 1650. Maybe there are issues with the half resolution version. The edges of the screen artifacts are due to the fact that it is a screen space effect and there isn't much that can be done there. Make sure you provide a reflection probe or an APV for the effect to fallback when failing the tracing.

    That said, maybe there is a bug that you found. Can you share a video comparing the artifacts in full screen and half so that I can validate the behavior? Thanks
     
    auzaiffe, Sep 29, 2022
    #4

  5. Deleted User

    Deleted User

    Guest

    Extremely sorry i cannot provide a video anytime soon :(, but the issue is very easily reproducible in the HDRP starter scene template, especially inside interiors when SSGI denoiser is set to half or low preset ssgi, noise and artifact's appears along the borders of screen when moving the camera, this maybe because of being a screen space effect or low fps... I was using reflection probe fallback while testing
    this, somone else's video can show you the issue


    BTW what method do u recommend to reduce noise in low light conditions??
     
    Deleted User, Sep 29, 2022
    #5

  6. Deleted User

    Deleted User

    Guest

    @auzaiffe
    Screenshot (230).png
    running on medium settings, the noise seems to be caused by SSGI
     
    Deleted User, Nov 2, 2022
    #6

  7. HIBIKI_entertainment

    HIBIKI_entertainment

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    Run one of the .bat files, we noticed sometimes just adjusting in the menu went buggy and didn't always apply the changes/causes crashes. Running a target bat file was a way to potentially fix this and then settings could change again.
     
    HIBIKI_entertainment, Nov 4, 2022
    #7

  8. Deleted User

    Deleted User

    Guest

    I will try running demo again, but i think it's always going to be noisy with RTX off

    This video tests the demo with RTX off (so it falls back to screen space) towards the end and gets the same noisy effect! I guess that SSR maybe the main culprit according to the video
     
    Deleted User, Nov 5, 2022
    #8

  9. HIBIKI_entertainment

    HIBIKI_entertainment

    Joined:
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    Ah my mistake, I was interpreting that you had raytrace on for some reason.
    I would agree with SSGI fallback this scene is certainly less than ideal, however, I believe the reason for this is the stock medium quality is on 64 steps in the raymarch, this isn't a lot for a scene with this level of complexity.

    SSGI is still really heavy, but the introduction of the RT denoiser really helps a lot, a good trade-off of performance/cost I think.

    SSGI does still resolve during the play menu, and I notice it mostly in the same places on medium.
    The one thing I do see is resolving raytraced reflections on, it seems to fix everything, albeit a cost of course.
     
    HIBIKI_entertainment, Nov 5, 2022
    #9
    Deleted User likes this.