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Jamel
01-01-2005, 05:40 PM
I am trying to create some realistic human skin textures and i am not having any luck. Is there somthing I am not doing right?? they look plastic and fake Is there any tutorials or can some body give me some tips?? thanks.

mattclary
01-01-2005, 08:26 PM
Inside LightWave (6 or 7).

Silkrooster
01-02-2005, 12:29 AM
Lightwave 3D 8 Texturing by Leigh vander Byl, also mentions skin textures.
Silk

operation
01-02-2005, 08:06 PM
you get more info here.

the trick is to use illumination, incidence angle and weightmaps ( and texture map).
if you have G2, you can use SSS ( fake SSS but it works pretty well).
you can take a look here for more info:

http://www.cgtalk.com/showthread.php?t=166228&page=9&pp=15&highlight=skin+shader

cheer up !

Operation :)

Integrity
01-04-2005, 03:45 PM
Just to add if you are using the Specularity setting in the surface panels thinking it will add to the realism, you should consider another technique. Lightwave's Specularity will do the opposite and make it look fake and like plastic, like you had mentioned.

In many definition's from artists to scientists, specular means a direct or sharp reflection (in appearance). When light hits an object it always reflects at the same angle as it hits...it's the microscopic geometry that spreads the light rays into different directions giving a surface a "diffuse" (spreading out, or blurred reflection) appearance; whereas diffuse is in some minds the opposite of specular. In Lightwave as far as I know it is actually implemented to mean the amount of light reflected while the color you set is the frequencies absorbed. The Specularity setting is just a fake way of producing intense bright reflections on the fly. And as operation suggested use incidence angle gradients all over the place since everything is considered a reflection.

Skin is very diffuse and the light that penetrates it actually reflects even more inside, eventually coming back out in a different position defined by the critical angle. As well as a certain amount of translucency. Its what gives it that "special" appearance that no one has been able to duplicate, but will be very soon due to increase in volume rendering and faster processors. This internal reflection is what operation was talking about called SSS (sub-surface scattering).

Texture wise look at other artists textures to see what they have done (within tutorials). Color, bump, specular (although it really defines what areas are more prone to highlights), diffuse (combination of other). For color some people's faces are red and peach in different areas...like some people have redder noses than others. Not only that but you have to take into account make-up. If your used to comparing a render to a person's skin in reality from a film...they were most likely wearing make-up to hide certain anomalies or add-on to an effect. That will play a major role. The bump map is also another major role...when I was first playing around with this stuff without a bump map the model will look like a perfect mesh...once I added a bump map to give irregularites it jumped to a realistic render. Not only that but you should use bump maps to define the microscopic geometry (obviously) that will determine the diffusion of your skin so quite simply you wouldn't even have to use the fake specularity...the bump map will diffuse everything accordingly.

Sorry for the long and probably unnecassary explanation but I figured maybe I'd give you a rap on the whole thing because some tutorials do not explain everything...not in definition...but just so you can understand it so later on (or before they explained) when they use it for something you know what their talking about.

I hope this helps.

sliver
01-04-2005, 03:56 PM
Have you tried the skin presets that come with v8? They are not great, but add your own colour textures and tweak a bit and you can get somewhere close.