Scene Space Directional Occlusion (SSDO)

Discussion in 'Wish List' started by Son Kim, Mar 18, 2009.

  1. Son Kim

    Son Kim

    New Member

    Joined:
    Jul 27, 2008
    Messages:
    22
    "Physically plausible illumination at real-time framerates is often achieved using approximations. One popular example is ambient occlusion (AO), for which very simple and efficient implementations are used extensively in production. Recent methods approximate AO between nearby geometry in screen space (SSAO). The key observation described in this paper is, that screen-space occlusion methods can be used to compute many more types of effects than just occlusion, such as directional shadows and indirect color bleeding. The proposed generalization has only a small overhead compared to classic SSAO, approximates direct and one-bounce light transport in screen space, can be combined with other methods that simulate transport for macro structures and is visually equivalent to SSAO in the worst case without introducing new artifacts. Since our method works in screen space, it does not depend on the geometric complexity. Plausible directional occlusion and indirect lighting effects can be displayed for large and fully dynamic scenes at real-time frame rates. "

    http://www.mpi-inf.mpg.de/~ritschel/SSDO/

    grab the paper and check out the video.
  2. jeffcraighead

    jeffcraighead

    New Member

    Joined:
    Nov 15, 2006
    Messages:
    740
    That is pretty impressive. I'll have to go over the paper later.
  3. megmaltese

    megmaltese

    Member

    Joined:
    Mar 19, 2009
    Messages:
    1,897
    OMG this is what every artist always wanted... no more dealing with shadows problems and so much time lost for for occlusion static maps and such. Hope somebody here will make a post process shader soon :D
  4. the_motionblur

    the_motionblur

    Member

    Joined:
    Mar 4, 2008
    Messages:
    998
    Woah! awesome. I guess that's a technique similar to the one I referred to in the other Indirect Lighting thread. Having that in Unity would be SO cool! 8)
  5. jeffcraighead

    jeffcraighead

    New Member

    Joined:
    Nov 15, 2006
    Messages:
    740
    After reading the paper, this seems like it could fit well into the current rendering pipeline (at least from my understanding of it) as an option. It would reduce the frame rate a bit (thus the option in maybe the Quality settings), but could drastically improve the rendering quality of the real time lighting and shadows.

    +1
  6. warby

    warby

    New Member

    Joined:
    Mar 23, 2009
    Messages:
    162
    yes i would love to have this in my game :D

    i dont think i have seen this implementation in any game engine yet could be quick a marketing hook for unity to have this first before unreal and cry engine :)
  7. aaronsullivan

    aaronsullivan

    Member

    Joined:
    Nov 10, 2005
    Messages:
    984
    Is this possible with a custom shader? I mean... do we have access to everything needed to write our own post-process shader for this? I haven't looked deeply into making my own shaders yet, but there's a good chance you don't need to wait for UT for this. :D

    Who will be the first to write it? Or at least explore the possibilities?
  8. jeffcraighead

    jeffcraighead

    New Member

    Joined:
    Nov 15, 2006
    Messages:
    740
    aaron, I was thinking the same thing, but I don't have the time to look into it at the moment. Maybe Aras could chime in and let us know if its at least possible with the tools available, then I might dig a little more when I get some time. I've been wanting to do some shader coding anyway.
  9. Daniel Brauer

    Daniel Brauer

    Member

    Joined:
    Aug 11, 2006
    Messages:
    3,233
  10. defmech

    defmech

    New Member

    Joined:
    Feb 24, 2007
    Messages:
    507
    I don't think Forest was doing scene space directional occlusion, just standard screen space ambient occlusion. This is a very different, but related method of simulating indirect lighting.
  11. CryptoQuick

    CryptoQuick

    New Member

    Joined:
    Apr 13, 2009
    Messages:
    38
    These advanced techniques are always fascinating. Here, check out what the folks at Ogre3D have been doing... Some shader code towards the middle of the first page:

    http://www.ogre3d.org/forums/viewtopic.php?f=11&t=46794

    Note that this is a comparison of his SSDO with static, baked AO. He doesn't compare with existing SSAO implementations.

    Apparently, from what I understand, this just adds some color to your SSAO without having more overhead than a comparable SSAO implementation. Trick is, SSAO adds a lot of that, regardless.
  12. llavigne

    llavigne

    New Member

    Joined:
    Dec 27, 2007
    Messages:
    976
    It's fantastic, imagine the market share this would generate (in the AAA/MOR segment)

    One great thing about better lighting is you can use less textures, therefore reducing the web server bandwidth

    And it would deal a death blow those who complain about how crappy unity shadows are ;)
  13. Daniel Brauer

    Daniel Brauer

    Member

    Joined:
    Aug 11, 2006
    Messages:
    3,233
    Oops, my mistake. That's what I get for not reading the paper.
  14. tarragon

    tarragon

    New Member

    Joined:
    Dec 28, 2010
    Messages:
    38
    It will take unity at least two weeks to implement it:( I can't wait.