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Ambient occlusion with temporal occlusion creates strange artefacts

Discussion in 'High Definition Render Pipeline' started by iSpiegelball, Feb 14, 2020.

  1. iSpiegelball

    iSpiegelball

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    ao_temporal.PNG

    As you can see in the picture, the cube geometry (red) has several "ghosts" (blue) in the Game View. This is only present if "temporal accumulation" is active for AO. To make it even stranger, resizing the Scene View(in a different window) shifts the ghosts in the game view.

    HDRP 7.2.1 with 2019.3.1f1 on Windows 10 (Bootcamp) and Radeon Pro Vega 56.
     
    iSpiegelball, Feb 14, 2020
    #1

  2. Bordeaux_Fox

    Bordeaux_Fox

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    I would not use the temporal setting for AO, as the tooltip also states, it's cheaper but creates also artefacts.
     
    Bordeaux_Fox, Feb 14, 2020
    #2

  3. SebLagarde

    SebLagarde

    Unity Technologies

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    Hi, Hi expect it is a fast moving cube right? Do you have a movie? thanks
     
    SebLagarde, Feb 15, 2020
    #3

  4. iSpiegelball

    iSpiegelball

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    Hey Sébastien,
    the cube doesn't move at all. You can notice the effect in this video (bottom right corner):

     
    iSpiegelball, Feb 18, 2020
    #4

  5. francescoc_unity

    francescoc_unity

    Unity Technologies

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    Hi,

    To be clear, is the issue happening only when resizing the various windows?
    Do you have animated material option enabled in the scene view? (If not you don't have motion vectors generated and the temporal reprojection will be faulty).
    Does this happen if you press play?

    Thank you
     
    francescoc_unity, Feb 19, 2020
    #5

  6. iSpiegelball

    iSpiegelball

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    The ghostings are also present if I don't resize the windows, but less noticable since they don't move. I have "animated materials" enabled, but disabling doesn't change the artefacts. All shown materials generate motion vectors. I have the same behaviour in play mode. Also I remembered a similar effect I saw a few days ago, where transparent materials produced wrong reflections with a planar reflection and resizing one window shifted the reflections in the other. I will share this too once I am able to reproduce.
     
    iSpiegelball, Feb 19, 2020
    #6

  7. francescoc_unity

    francescoc_unity

    Unity Technologies

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    I am confused on how you get ghosting with nothing moving? Does this happen if you have only one window open (say game view and play mode?)

    A bug report would be great so we can look into it!

    Thank you
     
    francescoc_unity, Feb 19, 2020
    #7

  8. iSpiegelball

    iSpiegelball

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    iSpiegelball, Feb 19, 2020
    #8

  9. francescoc_unity

    francescoc_unity

    Unity Technologies

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    Hi,

    We identified and fixed the issue, not sure yet what public package it will be on, but likely the next one that we'll publish.

    Thank you
     
    francescoc_unity, Feb 26, 2020
    #9
    chap-unity likes this.