Search Unity

Why does my Screen Space Reflections look so weird?

Discussion in 'Global Illumination' started by expcalibur, Sep 5, 2021.

  1. expcalibur

    expcalibur

    Joined:
    Nov 3, 2020
    Posts:
    25
    Hi! I was experimenting with the SSR of the PostProcessing stack in Unity Built-In renderer and I got this problem (or not?). Does anyone know why this happens?

    upload_2021-9-5_17-46-55.png
     
  2. AcidArrow

    AcidArrow

    Joined:
    May 20, 2010
    Posts:
    11,729
    Because Screen Space reflections as a method generally sucks ass and it is a failure of graphics programmers and tech artists everywhere that we don't have a better (and performant) solution by now.

    If it's something you don't see with the camera, it can't be used for reflections. So now you're looking a bit downwards and you're missing the walls and ceiling that are supposed to be reflected, there is nothing for SSR to use.

    Try placing a reflection probe covering that room, so at least when SSR has no data it falls back to something that at least is vaguely the right color.
     
    Last edited: Sep 6, 2021
  3. expcalibur

    expcalibur

    Joined:
    Nov 3, 2020
    Posts:
    25
    Well, that's something. So you say like, maintain the SSR the way It is now but add a reflection probe to the entire room? I'm a bit confused because I've already tried to use reflection probes in some especific areas (4 for that single room) and they did not blended very well. Any tips on that?

    And also, thanks for the answer!
     
  4. AcidArrow

    AcidArrow

    Joined:
    May 20, 2010
    Posts:
    11,729
    Are you using built-in / HDRP / URP?

    Not sure if it applies to what you are using, but the idea used to be that you had a cubemap set up as well as you could and then used SSR on top of it for more accuracy, but when it fell back to the cubemap it would at least be in the same range of colors (and not super bright as in your image) so the transition would be far less obvious.
     
  5. expcalibur

    expcalibur

    Joined:
    Nov 3, 2020
    Posts:
    25
    I'm using Built-In. As for the cubemap, I'm using a skybox right now from the AllSky free asset in the asset store. But I think I get the idea, use the cubemap for the base reflections, SSR to increase reflection accuracy and also a reflection probe to complement the SSR. Is that it?
     
  6. AcidArrow

    AcidArrow

    Joined:
    May 20, 2010
    Posts:
    11,729
    Yes, that's more or less it.