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dark_lotus
09-20-2002, 08:13 AM
Hey everyone,

This tutorial was done in Lightwave, but the theory can be applied elsewhere.

Afew people have asked me how i acheived my skin texture on my female model which can be found
here (http://www.cgtalk.com/showthread.php?s=&threadid=21614).

Or have a look at the attached image.

dark_lotus
09-20-2002, 08:35 AM
How this is achieved is by using 2 gradients.

For the base I just used the following:

[Ref: Figure 1.]
Colour R: 171 G: 050 B: 000
Diffuse: 86.5%
Lumnosity: 7%

In the Colour, open up Texture (The 'T' button).

Replace the first layer with a gradient:
---------------------------------------------------------------
[Ref: Figure 2.]
Input Parameter: Light Incidence

At Parameter 90 put a bar:
Colour R: 255 G: 176 B: 000

Alpha: 100%
---------------------------------------------------------------
Duplicate the layer. And put in the following.
[Ref: Figure 3.]

For Parameter 90:
Colour R: 249 G: 188 B: 134

Alpha: 100%

=========

Now add another bar at Parameter 55.

Make it White, and give it an alpha value of 20.


-----------------------------------------------------------------

Make sure that the scene light is selected for each of the gradients.

Voila!
You have now created a texture that simulates SSS. Any questions please feel free to PM or email me.

dark_lotus.

leigh
09-20-2002, 11:56 AM
Hey :)

I'm not really sure how this can simulate SSS when SSS is more to do with diffusion and translucency than colour :surprised
It is therefore something that affects the way light illuminates it, so I guess there would be some degree of tonal change, but it would have more to do with a luminscent quality than anything else, as I understand it.. :shrug:

dark_lotus
09-20-2002, 12:34 PM
I'm not really sure how this can simulate SSS when SSS is more to do with diffusion and translucency than colour

It gives the appearance of SSS. So it kinda fakes it i think is a better way of describing it.!

Thanks

leigh
09-20-2002, 12:36 PM
Oh right ;)

Kinda like my uber-fake velvet trick ;)

dark_lotus
09-20-2002, 01:08 PM
here it is for you to download.

Cman
09-20-2002, 02:10 PM
Thanks for posting the textures. :)

theMax
09-20-2002, 03:49 PM
Cool thanks!!!!

Now I'm off to fake SSS in Max 4 (or I'll just go and download the Brazil test like ever one else...:p)

But Leigh dose bring up a good point, in LW is there a way of "linking" the gradient nods to the light value nod. That way it mite work for doing animations and not just stills.

I don't have LW so there’s really no way for me to use the texture if I downloaded it. Anyway, how long is it taking for that to render?

Thanks for the idea, it's something to play with...

dark_lotus
09-20-2002, 08:37 PM
But Leigh dose bring up a good point, in LW is there a way of "linking" the gradient nods to the light value nod. That way it mite work for doing animations and not just stills.


umm it is linked to the light: hence 'light incidence"


Render times are being quite awkward. It on enhanced low AA, Ray Traced Reflections, and Shadows. One Area Light,

and each frame render time is between 3 - 20 minutes. The closer it is to the camera the longer it takes.

And the file was for all those oh 5 people who downloaded it.

takkun
09-20-2002, 08:54 PM
I'll download it when I get home, maybe you should change the name of this trick to Kick-Ass Skin texture instead of fake-SSS, you might get less gruff that way.

Bytehawk
09-20-2002, 11:59 PM
thanks
'preciate it

cheers

Killer03
09-23-2002, 07:33 PM
Thanks for the Help. I Will give it a try ..

dark_lotus
09-23-2002, 08:42 PM
I apologise for any confusion - its not really SSS, its just a way of having multiple layers of the epidermis (skin).

I got exited cause my render looked really good.

So Peace.


Yeah.

psumo
09-23-2002, 08:57 PM
hmm.. I don't get it
it doesn't look like sub surface scattering
of flesh to me

kinda looks plastic

dark_lotus
09-23-2002, 09:16 PM
READ THE REPLIES FOR THE LOVE OF GOD.

Geez

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