Working on MakeHuman, we have finally found the most easy and robust way to have sss in human skin.
We have written a short article (it’s WIP !) about how to obtain a good SSS effect using Blender and Gimp.
Take a look, and when you improve the basic tecnique (I’m sure of this!) report me the most impressive images.
Note this is the most basic implementation of this method, perfect to explain the
concept, but, of course, it’s possible work without use Gimp, in example with these nodes (thanks Alessandro Proglio):
Interesting tut you’ve got there Manuel!
Oh, and I hope makehuman is progresing nicely as it is so useful to me at the moment. Keep up the great work I’m seeing on the Makehuman blog!
We didn’t know about Matt’s article, yes, it’s the same thing, with a faster method than using Gimp. I’ve also tried using nodes, an even better way for me, since with the compositor we can separate the channels and simulate more precisely the different behaviour of the light, and the result can be corrected with RGB curves.
Here are more images from our tests:
A simple model with a flat color, without textures and head
The same model but the sss channel is mixed with the render using the “overlay” method.
That certainly is looking very close to what I was getting a few years back from my own renderer. You might remember Manuel, I think you saw that too back then on the old yafray forums.
Thing is, I found these color changes not very natural looking, and worked on it so long trying to improve it that I eventually grew tired of it, and so never did anything with it (as usual…)
Anyway, as reference, for those that didn’t see it back then, here is what my results looked like for skin, upper left is without sss, the others are various tweaks of the sss method I was using.
As for blurring, you probably want to use a special kind of blur. If you could make a graph of it, it would look like a fast exponential falloff, not like a gaussian blur or any other filters available in blender, but with a sharp peak at it’s center, then decaying fast.
At least, that is what I think it looks like, can’t remember anymore, too long ago.
I’ve made a compositor node that does that same effect, but without the need for a uv map and baking, and the exponential falloff functions built-in. So no translucency, but only ‘blurring the light’ over the surface as done here. If you’ve got a blender compiled you can try the patch: http://users.pandora.be/blendix/scatter.html
That is all looking very good brecht, well done! From a very quick look at the source, it all looks quite familiar I spent so long tweaking all those equations…
Anyway, very well done, brecht, Keep up the good work! :yes:
Hey Brecht, that is a nice compositor node… If you read this I do have a few questions:
Is it reall SSS or still some kind of fake method?
This is now a compositor node, but is there also some way of making it a material node?..so that you could specify the scattering per material…
We didn’t know about Matt’s article, anyway the simulation of different light frequency scatter is very important to have a good result. Anyway we can do all using only Blender:
