Home Technical Talk

Please tell me which houses have correct Ambient Occlusion maps?

cubrman
polycounter lvl 6

Replies

  • cubrman
    Offline / Send Message
    cubrman polycounter lvl 6
    The reason I'm asking is micro-shadows. They work pretty well in Unity now, but only if you DO NOT have dark gradients like on building (1)


  • poopipe
    Offline / Send Message
    poopipe grand marshal polycounter
    I've got no idea what a micro shadow is but ... 

    Assuming you have screenspace AO (or equivalent) an ambient occlusion texture should look like a cavity map - i.e it should only be dark in cavities and white everywhere else. The screenspace AO takes care of the larger scale ambient occlusion.
    If the texture is mostly gray, your asset will look darker than it really is under indirect lighting - a situation which often leads to people adjusting the wrong things to compensate. 

    The occlusion distance you want depends on your game camera  - if it's an FPS you want a small range (a few cm), if its a top down game you'll probably want a larger range. 


    in that picture, 3 and 4 aren't bad but the occlusion distance is probably a bit higher than it could be
    2 is awful
    1 is kind of ok if you ignore the gradient near the floor




  • cubrman
    Offline / Send Message
    cubrman polycounter lvl 6
    @poopipe thanks! That was very helpful.
  • gnoop
    Offline / Send Message
    gnoop sublime tool
    I have a question too.   Isn't AO should be clipped withing  shadows  or  clouds shade  and under direct light we shouldn't see it at all basically?     I always thought it should be working that way.   Perhaps  just by  much more overwhelming  sun intensity vs AO  or simply by adding shadow map to AO before rendering.      So whatever gradient on building1 is  it  should be seen only in shades?


  • Shrike
    Offline / Send Message
    Shrike interpolator
    Yes the direct lighting should remove the AO, however the AO debug view does not take that into account, so it does still happen unless you manually put the AO into the diffuse

    The HDRP Micro shadows expect correct AO Maps and will heavily overdo the shadowing if the AO maps are overdone by default.
    Nr 2 looks the most typically baked, however it has a bad gamma curve applied, similar to how marmosets overdoes the AO bake, and as such covers way too much in dark. Try remove SRGB from the texture at least, that will improve it a bit.

    Id definitely recommend having a ground contact like on 1, the issue there is that you did not add AO decals or AO on the ground. The AO of the wall is perfectly fine (maybe a bit strong) but the ground is missing its AO and you should aim to solve this.

    Always put AO decals below your objects, it makes a large difference. The contact area between objects is one of the main deciding factors of final visual quality in my opinion.
  • Shrike
    Offline / Send Message
    Shrike interpolator
    Here is how it should look ideally 
    This is with SS Raytracing



    (well also not perfect since its covering too much in shadow also)
    This SSRT does a very surprisingly good job tho on even the tiny details

    Here is more the cold reality of realtime lol with ao decals and mixed quality bakes


    Looks pretty crap in debug view
    But in normal game view with SSAO dosnt look half bad and sometimes hard to distinquish, IF you do put proper object contact and proper AO decals.


  • cubrman
    Offline / Send Message
    cubrman polycounter lvl 6
    @Shrike damn, dude, thanks for the awesome post! I'm a big fan of your game!

    I have an unexpected trick up my sleeve) The level you see was made from a real location:

    https://www.google.com/maps/@38.915573,-77.0219884,3a,66.3y,333.03h,85.71t/data=!3m6!1e1!3m4!1s4JGrR3Uw1e6_tye-nzbRsA!2e0!7i16384!8i8192?entry=ttu



    I guess it was a bit stupid of me to ask this question, when I already have good references, but this was me making that AO map back when I decided to add bent normal maps to every object in the level. It helps to shader objects better in the shadows - maybe that's why I did not see my mistake up until I started using micro shadows. No, I think adding ground contact AO would work for me.
  • cubrman
    Offline / Send Message
    cubrman polycounter lvl 6
    By the way, SRGB advice is golden, but I already do it. Still I would redo all AO maps with smaller occlusion range to recuse the AO spread.
Sign In or Register to comment.