Separable Subsurface Scattering in UE4 ?

Greetings everyone. My thread is adressed to Epic devs mainly. In fact Mr Ivey told me to make a thread about it so devs will look into it. Many of you surely know Jorge Jimenez: the creator of SMAA and SSSSS (Screen Space SubSurface Scattering) which was included in 4.5 update. Well genius never stops his advancements and created with other geniuses a better version of SSS (Screen-Space being the least perfect in approximations) and called it Separable SubSurface Scattering. Here is his tech explained in those two videos:

Research papers are available here at Károly Zsolnai’s page : Separable Subsurface Scattering – Computer Graphics Forum 2015 (presented at EGSR 2015) – J. Jimenez, K. Zsolnai, A. Jarabo, C. Freude, T. Auzinger, X-C. Wu, J. von der Pahlen, M. Wimmer and D. Gutierrez – Károly Zsolnai-Fehér – Research Scientist

I hope Epic staff take note about it and try to contact him and get it in UE4.

Edit : Oh what? The explanatory video has been put to private. It explains everything about the new tech. In his site it says: "Talk (unofficial) – temporarily disabled, it may be back soon!

UPDATE: Separable SSS is officially released now

Source code available on GitHub: GitHub - iryoku/separable-sss: Separable Subsurface Scattering is a technique that allows to efficiently perform subsurface scattering calculations in screen space in just two passes.

Okay…somehow, only the first video was working, but man, I have to admitt though that looks really impressive! I would love to see in Unreal, but…

two things come into my mind, that I have to ask, mainly also to the devs:

  • I would love to see integrated, but only if it perfroms better in terms of gpu performance than the current implementation does. I tested 10 characters in a IBL lit environment with one directional light, and those characters had only shorts on, so quite a lot of skin to see. The ss profile shader was between 10 to 12ms slower than the default ss shader. So almost an unacceptable performance drop in a real use case.
  • If one is not performing better, I would really prefer making the current version run better, than going for a not optimized protoype kinda thing.

Please dont get me wrong, is really just honest feedback about my performance concerns. Let me know if you have any cool ideas for .

Cheers! :slight_smile:

Oh what? The explanatory video has been put to private. It explains everything about the new tech. In his site it says: “Talk (unofficial) – temporarily disabled, it may be back soon!”

I remember hearing Martin Mittring talk about on one of the recent streams (couple months back). He was going over the new SSSS and ways to improve it in the future… I don’t have time to re-watch the whole thing, but here is the stream if you are interested: - YouTube

Martin is definitely one of the ones to talk to about though, hopefully he can add more info once the weekend is over. :slight_smile:

article writer claims he got in touch with the dev of tech and that can be added to all engines: SSSS - New Skin Technique - Can Be Added to All Engines with Ease, Can Run On "Pretty Much Anything"

Please Epic, add it to UE4.

I would also love to see implemented. Hope that Epic looks into .

Seeing how they made the code freely available to everyone, and it being a post-effect, shouldn’t be much of a task for some wiz at Epic. :slight_smile:

Here is the full interview : Doctoral Researcher "Karoly Zsolnai" Talks About Separable Subsurface Scattering & Its Benefits

Now Epic really needs to contact dev and implement in UE4 !

My with making SSS a post-process effect is it softens details along the skin that it shouldn’t. Yes, interscattering does occur beneath the skin, but on top of the skin is a layer of oil that gives it a well-defined shine separate from the SSS effect. And other surfaces like marble also have a nicely-polished clear-coat effect, so sharp texture detail on top of the surface, and interscattering underneath. I really don’t like how the subsurface profile shader will deliberately blur textures and surface detail. If method has to be a post process effect, it would be nice to mask it out based off of textures on the model so you don’t have to sacrifice sharp detail to get it.

UPDATE: Separable SSS is officially released now

http://www.iryoku.com/separable-sss-released

Source code available on GitHub: GitHub - iryoku/separable-sss: Separable Subsurface Scattering is a technique that allows to efficient

Wow ! And I was trying to cook up one for myself :smiley: Lol that is just great man ! And I know many of these people from.

I swear, forum is just like a one great family re-union :smiley: :smiley: :smiley:

EDIT: Can we get on Roadmap on trello ? Really ? I want .

mk.jpg

OK, yes, I want . Also, that face was insanely epic.

Anybody knows How to implement or work with shader inside UE4?. Many thanks